Age-related and thymus-dependent rejection of adenovirus 2-transformed cell tumors in the Syrian hamster. Adenovirus type 2-transformed hamster cell-induced newborn tumor lines were usually rejected when transplanted s.c. into 21-day-old syngeneic, weanling hamsters. The tumor-inducing capacity of two of these lines (Ad2HTL3 and Ad2HTL6) was tested in intact and neonatally thymectomized hosts. After s.c. injection of suspensions prepared from these lines, none of the weaning hamsters developed tumors while 100% of the newborns and 35.2% of neonatally thymectomized, weanling hamsters developed progressively enlarging neoplasms. The susceptibility of neonatally thymectomized hamsters to tumor challenge was directly related to the degree of immunosuppression observed following thymectomy as indicated by the amplitude of the in vitro response of blood leukocytes to concanavalin A. Pretreatment of thymectomized weanlings with syngeneic adult lymphoid cells (i.p.) resulted in a significant reduction in tumor susceptibility (p = 0.03). These findings suggest that acquisition of resistance to adenovirus type 2-transformed cells during the first 21 days of life may be a thymus-dependent cellular immune process.


Deficiency of antibody-dependent cellular cytotoxicity and mitogen-induced cellular cytotoxicity effector cell function in patients with acute myelogenous leukemia in remission. Patients with acute myelogenous leukemia in remission have pronounced deficiency in antibody-dependent cellular cytotoxicity (ADCC) and mitogen-induced cellular cytotoxicity. The deficiency in ADCC was partly explained by reduction in the number of circulating effector cells (Fc receptor-bearing cells) demonstrable at a time when white blood cell and platelet counts were normal. These cytotoxic functions, as well as the circulating numbers of T-cells and Fc receptor-bearing cells were further decreased by the administration of monthly cycles of combination chemotherapy with 1-beta-D-arabinofuranosylcytosine and 6-thioguanine. Following each cycle of chemotherapy, progressive recovery of these functions occurs during the third and fourth weeks with occasional increases above base line in patients in whom chemotherapy is withheld for longer than five weeks. In selected patients recovery of one cytotoxic function preceded the other, indicating that these functions are mediated by different effector cells. Administration of a single dose of daunomycin i.v. had no effect in either of these cytotoxic functions or in the circulating numbers of lymphocytes. The decrease in ADCC effector cell function induced by phase cycle-specific agents correlated with the level of reactivity exhibited by patients after achieving bone marrow and clinical remission. Patients showing low levels of reactivity postremission experienced highest degree of depression. In two patients, complete abrogation of ADCC effector function was demonstrated with minimal recovery even six weeks after stopping chemotherapy. These findings indicate that effector cells in ADCC and mitogen-induced cellular cytotoxicity are highly susceptible to phase cycle-specific agents, and their recovery takes longer that of other lymphoid and nonlymphoid populations.


New dose-time relationships of folate antagonists to sustain inhibition of human lymphoblasts and leukemic cells in vitro. In this study, three methods are utilized to analyze toxicity produced by methotrexate and the lipid-soluble antifolate, 2,4-diamino-5-(3',4'-dichlorophenyl)-6-methylpyrimidine, in human lymphoblasts (WIL-2) and leukemic cells. These methods detect increasingly severe metabolic damage; inhibition of deoxyuridine incorporation into DNA, the reversibility of inhibition of deoxyuridine incorporation by supplementation with formyltetrahydrofolate as Ca2+ leucovorin, and the ability of cells to form clones in soft agarose. The critical dose and exposure time for establishing and maintaining the metabolic toxicity of methotrexate is examined in detail. It is shown that, if an initial loading dose of methotrexate is of high enough concentration or is maintained for a sufficient period to achieve greater than 98% inhibition of deoxyuridine incorporation, this inhibition can be sustained by low concentrations of 2,4-diamino-5-(3',4'-dichlorophenyl)-6-methylpyrimidine or methotrexate. Concentrations of methotrexate or 2,4-diamino-5-(3',4'-dichlorophenyl)-6-methylpyrimidine that equal or exceed 0.1 microM are sufficient for maintenance of inhibition by an initial loading dose of methotrexate but escape from inhibition that occurs if lower levels of drug are used. The possible implications of these observations for in vivo protocols are discussed.


High-dose methotrexate in malignant melanoma. High-dose methotrexate was given to 28 patients with advanced malignant melanoma who had previously failed to respond to two chemotherapy protocols. There were five instances of serious, but not fatal, toxicity. One patient has had an objective response and seven patients have had stabilization of disease with an average duration of 4 months.


Thymus derived inhibitor of lymphocyte proliferation. I. Isolation and assessment of tissue specificity. Preparations from bovine thymus tissue were analyzed for their inhibitory effects during in vitro lymphocyte proliferation. The results indicate that these preparations strongly inhibit DNA synthesis in stimulated human peripheral lymphocytes, bone marrow cells, thymocytes and lymphoblastoid cells. This inhibition was dose-dependent and not due to cytotoxicity of the preparations. No inhibition was found of the spontaneous proliferation of HeLa cells and human fibroblasts indicating that the inhibitory effect was specific for proliferating lymphocytes. Control preparations from bovine liver or kidney did not show any suppression in the test systems used.


Marginal bundles of axoplasmic microtubules at nodes of Ranvier within muscle. Using a special albumin technique, nodes of Ranvier have been examined within frog skeletal muscle, sciatic nerve and rat and frog cerebrum. Initial segments have been examined in cerebrum of frog and rat. Mictotubules usually run longitudinally through these regions, but within the bare area of the intramuscular node of Ranvier, annular or helical bundles of microtubules run in a marginal band at right angles to the more centrally placed longitudinal microtubules. These nodal bare areas show a pronounced convexity and it is suggested that the annular microtubules serve to maintain this convexity during muscle contraction.


The filum terminale of the frog spinal cord. Light and electron microscopic observations. The filum terminale, or terminal portion of the spinal cord, was studied in normal adult frogs (Rana pipiens) bu means of light and electron microscopy. Astroglial cells are the predominant elements in this region. The rostral portion of the filum terminale consists mainly of (1) a peripheral dense ring of myelinated and some unmyelinated nerve fibers, and processes of astrobytes terminating at the subpial space; (2) an intermediate zone, in which astrocytes are the main cellular elements in addition to a few degenerated neurons; and (3) a central region where the central canal is lined by dark and light ependymal cells. In the caudal portion of the filum terminale, the amount of neuropil is greatly reduced. This region os formed mainly by astrocytic glial cells and very few neuronal elements. The central canal in the caudal portion is located ventrally and contains a lining consisting almost exclusively of dark ependymal cells.


Epidemiological basis for the prevention of coronary heart disease. Epidemiological studies have laid the basis for a preventive approach to coronary heart disease (CHD). On balance, present evidence indicates that the following should form the basis of a preventive programme: low-fat diet, cessation of smoking, and control of blood pressure. Other factors likely to produce a beneficial effect on CHD occurrence include reduction of obesity and increased physical activity. Although psychosocial factors are most likely to be causally related to CHD, it is not possible at present to provide clear guidelines as to their role in a preventive programme.TRIALS ARE BEING CONDUCTED TO INVESTIGATE THE POSSIBILITY OF PREVENTING CHD BY A VARIETY OF APPROACHES: a doctor-centred approach or health education in certain sectors of a community or in whole communities. These trials have shown that it is possible to achieve behavioural changes and a reduction in the levels of risk factors in a proportion of the participants. It is not yet clear to what extent these changes in levels of risk factors in middle-aged people will lead to a reduction in the incidence of CHD. It can be calculated, however, that the greatest benefit is likely to come from approaches to prevention that involve the whole community, rather than only high-risk groups.


Zoonotic aspects of filarial infections in man. This article gives an account of the filarial parasites found in man and their potential transmissibility to and from other vertebrate animals under natural and experimental conditions.Those species that are regarded as being primarily parasites of other vertebrates, but which also infect man, are then dealt with in greater detail. These include the subperiodic strain of Brugia malayi and perhaps also B. pahangi, both of which are found in wild and domestic carnivores and monkeys, and Dirofilaria species of dogs and racoons.The Brugia parasites develop to maturity with the production of microfilaraemia and clinical manifestations in man similar to those caused by periodic B. malayi in man. Human dirofilariasis, on the other hand, represents a transmission cul-de-sac for the parasite. Clinical manifestations are mild or absent and generally the worms do not mature and, even if they do, they rarely give rise to microfilaraemia. D. immitis causes pulmonary dirofilariasis, and D. repens and D. tenuis give rise to subcutaneous nodules in man. The diagnosis of dirofilariasis depends on an awareness of the infection in the animal reservoirs and of the possibility of man being exposed to bites of infected vectors.


The psychiatric aspects of tropical disorders. The nature of psychiatric disorders in tropical regions is affected much more by the effect on the patient of certain environmental and cultural factors than by any specific features of tropical diseases. In places where the standards of health care and health education are not yet fully developed, abnormalities of physical development, particularly those affecting the development of the cerebral cortex, are of great importance. For example, protein-energy malnutrition may result in deficits in cerebral maturation and efficiency that reduce the capacity of the brain to manage its behavioural functions and may give rise to impaired capacities for concentration, foresight, and judgement and impairment of inhibitory control over intensely experienced emotions. In addition, certain cultural attitudes that are widespread in pre-literate societies influence the type of secondary reaction to disease: for example, acute symptoms tend to be florid and uninhibited, and violently experienced and externalized emotions such as hilarity, terror, anger, and grief are the rule rather than the exception.Certain tropical diseases are, however, the direct cause of severe disturbance of cerebral functioning, while others affect only the finer cerebral controls so that normally controlled fears, anxieties, and other personality traits emerge. These specific brain syndromes may be acute or chronic and may be triggered by an apparently trivial physical cause. Acute brain syndromes appear to be more common in tropical countries perhaps because in the adult the cerebral cortical reserve is less than it ought to be because of the prevalence of earlier minimal brain damage. Formal psychiatric reactions are, of course, also seen in tropical countries, but the expression of, for example, schizophrenia, hypomanic and manic states, and depression is coloured by the underlying personality and the cultural background of the patient. Perhaps in no other setting is the intimate relationship between behaviour and the physical body seen more clearly than in populations living in the tropics and it is important that health workers in these regions should be aware of the role played by earlier or concurrent physical disease in behavioural disturbance.


Epidemiology of the hypertensive disorders of pregnancy. Disorders associated with hypertension during pregnancy, which are often linked with oedema and/or proteinuria and are variously termed toxaemia of pregnancy, EPH gestosis, pre-eclampsia, and eclampsia, are of unknown etiology, although they have been known for a long time and many attempts have been made to classify and explain them. In this paper, the author draws attention to the problems of standardizing values for blood pressure, proteinuria, and oedema and of determining their value in the diagnosis of the disorder. Different classification schemes are described and the problems of comparison between them are stressed. The frequency of the hypertensive disorders of pregnancy in different countries and groups at special risk are discussed. Finally, recommendations are made on the types of research and health care needed to combat the problem.


An epidemic of Rift Valley fever in Egypt. 1. Diagnosis of Rift Valley fever in man. Rift Valley fever (RVF) virus was isolated from 53 of 56 sera collected from patients with a clinical picture of dengue-like illness during the peak of the epidemic of RVF in Egypt in the autumn of 1977. RVF virus was also isolated from the throat washings of two patients and the faeces of four, all of whom were positive for virus isolation from the serum. All the isolates were identified by the complement fixation (CF) test. Serological diagnosis of RVF, using paired sera from 16 patients, was made by both the haemagglutination-inhibition (HI) and CF tests. HI antibodies were demonstrated in all the acute sera, whereas CF antibodies, which seem to appear later, were detected in only seven acute and twelve convalescent sera. A longer period than the 12 days in this study must be allowed to elapse between the taking of the paired sera for a definite serological diagnosis to be obtained, especially when CF antibodies are taken into account.


An epidemic of Rift Valley fever in Egypt. 2. Isolation of the virus from animals. During the epidemic of Rift Valley fever (RVF) that occurred in Egypt and other areas of North Africa in 1977, the virus was isolated from various species of domestic animal and rats (Rattus rattus frugivorus) as well as man. The highest number of RVF virus isolates were obtained from sheep; only one isolate was recovered from each of the other species tested, viz. cow, camel, goat, horse, and rat. RVF virus was reisolated from both camel and horse sera, apparently for the first time.


Congenital rubella in the USSR.

Congenital rubella in the USSR. The results of a comprehensive study of the problem of congenital rubella in Moscow and other cities of the USSR are presented. The highest rubella incidence was found among children 1-7 years of age; but 20-25 rubella cases were also recorded annually per 100 000 adults. Specific antihaemagglutinins were found in 36-70% of children and in 91-99% of adults. Investigation of the rubella foci revealed clinical rubella, confirmed by laboratory methods, in children and adults who had low initial titres of specific antihaemagglutinins. Serological screening of 1661 apparently healthy pregnant women detected antihaemagglutinins in 98.4%; however, low (1:8-1:16) titres were found in 53.3% and high (postinfection) titres and specific IgM in only 8.8% of cases.A study of 523 pregnant women who had been in contact with a source of infection revealed clinical rubella in 10.9% and inapparent infection in 0.7% of cases. A virological study of fetuses from infected pregnant women showed that there was intrauterine viral infection in 73% of cases; 38% of rubella-infected fetuses had congenital defects (unilateral or bilateral cataract, absence of one cerebral hemisphere, adhesion of the upper and lower eyelid, or diffuse damage of the crystalline lens); in one woman rubella virus was isolated from the fetuses and abortion materials received from two abortions with an interval of 6 months. Serological investigation of 519 mothers who had given birth to children with congenital defects showed that there were more frequent indications of rubella infection in the mothers of the children with CNS and cardiovascular defects, as well as in the children with congenital cardiovascular and CNS defects, than in the control groups. These data confirmed the teratogenic nature of rubella strains found in the USSR. This study indicates the need to improve rubella surveillance in pregnant women and to consider the prophylaxis of congenital rubella in the USSR. (See also Addendum.)


Diversity of influenza A virus subtypes isolated from domestic poultry in Hong Kong. The second phase of a 2-year influenza virus surveillance programme of domestic avian species in Hong Kong (up to October 1977) yielded influenza A virus, Newcastle disease virus, and Hong Kong paramyxovirus, as well as unidentified haemagglutinating agents. These viruses were isolated from the trachea or cloaca of apparently healthy domestic ducks, geese, and chickens originating from China and Hong Kong. Twenty-five combinations of haemagglutinin and neuraminidase surface antigens were identified from the 136 influenza A viruses isolated. Eight of the combinations do not appear to have been previously reported - Hav3Nav2, Hav4Nav2, Hav4Nav4, Hav4Nav5, Hav4Neq1, Hav6Nav4, Hav6Nav6, and Hav9Nav1. The existence of such a diverse pool of influenza virus genetic information may play a role in the emergence of new human pandemic strains.


Reappearance of H1N1 influenza virus in man: evidence for the persistence of the virus in domestic chickens. Serological studies on domestic poultry originating from China and Hong Kong suggest that the H1N1 virus may have persisted in domestic chickens prior to its reappearance in man in 1977. Experimental infection of young, local strains of poultry provided equivocal evidence that 4-day-old chickens could be infected; virus was not recovered from infected 1-month-old chickens.


The risk of optic atrophy following suramin treatment of ocular onchocerciasis. Treatment of onchocerciasis with suramin in an area of vector control led to an increased incidence of optic atrophy in treated patients compared to an untreated group.


Techniques of induced abortion, their health implications and service aspects: a review of the literature. This literature review indicates that menstrual regulation during the fifth to seventh week of pregnancy is not always as free from risk as has sometimes been claimed. In particular, it has a higher failure rate, in terms of continued pregnancy, than has abortion by suction in later stages of pregnancy.Vacuum aspiration is still the method of choice until the beginning of the eleventh week of pregnancy. After that, it seems to be slightly more hazardous than dilatation and curettage (D & C). Preoperative cervical dilatation seems to be beneficial after the tenth week, even though its effectiveness in preventing cervical tears and subsequent cervical incompetence in primigravidae remains to be definitely proven.For second trimester abortions, there is an urgent need for controlled studies, in the thirteenth to fifteenth week, to compare the increasingly popular modified D & C technique with various two-stage techniques, both in terms of safety and of cost-effectiveness. Prostaglandins for second trimester abortions have not quite fulfilled their promise as a relatively risk-free technique; they do, however, decrease the time interval between the administration of the abortifacient and the expulsion of the fetus.Aspects of abortion care other than the purely technical ones are much less well covered by research. For instance, very little is known about the acceptability of various abortion and anaesthetic techniques to either pregnant women or hospital staff. More studies are also needed on the interaction of pregnant women with the service providers at various levels and on how this affects their subsequent reproductive behaviour.


Perilymph fistulae.

Perilymph fistulae. A small series of 14 post-stapedectomy fistulae illustrates the varied aetiology. The long-term competence of the oval window seal may be ensured by making a small hole in the footplate. Contraction of ageing fibrous tissue contributes to late stapedectomy failures. Long-term follow-up is important, for any deterioration in hearing after stapedectomy may result from a perilymph leak.


The immunological effects of thymectomy in myasthenia gravis. Thymus-derived (T) lymphocytes in the peripheral blood and cellular immune function have been studied in ten patients with myasthenia gravis and in fifteen different myasthenic patients more than 10 years after thymectomy. The results were compared with those of a normal control population. The non-thymectomized myasthenic patients had normal T lymphocyte concentrations measured by rosetting with native sheep red cells. These patients also showed normal sensitization and recall of delayed hypersensitivity, phytohaemagglutinin (PHA) induced lymphocyte transformation and antibody-assisted (K cell) cytotoxicity; however, PHA-induced cytotoxicity was markedly reduced (P less than 0.001). The thymectomized group exhibited a lower mean percentage and absolute number of E-rosette-forming cells, which returned toward normal after in vitro treatment with thymosin. PHA-induced lymphocyte cytotoxicity, however, was normal in the patients who had undergone thymectomy, as were lymphocyte transformation, antibody-assisted cytotoxicity and sensitization to dinitrochlorobenzene (DNCB); there was a decrease in recall of established delayed hypersensitivity. Adult thymectomy in man, therefore, produces a partial and dissociated decrease in T cell responses and it is unlikely that the beneficial effect of this operation in myasthenia gravis is related to immunosuppression.


Effects of repeated Corynebacterium parvum and BCG therapy on immune parameters: a weekly sequential study of melanoma patients. I. Changes in non-specific (NK, K and T cell) lymphocytotoxicity, peripheral blood counts and delayed hypersensitivity reactions. Increased lymphocyte cytotoxicity, particularly of 'killer' K cell type was recorded with repeated immunizations of either C. parvum or BCG. A 3 week interval between immunizations was capable of maintaining the increase in cytotoxicity. No marked alterations of 'recall' skin hypersensitivity reactions nor of peripheral blood counts were noted. Expression of cytotoxicity results as percentage 51Cr release, lytic units/ml and cytotoxic capacity (after logit transformation of the cytotoxicity-lymphocyte curves) are described. A 3 week immunization schedule is suggested where BCG and C. parvum are used as immunotherapeutic agents, in the doses quoted.


The in vitro effect of a calf thymus extract on the peripheral blood lymphocytes of sixty-six melanoma patients. The in vitro effect of a calf thymus extract (TP-1) on peripheral blood lymphocytes was evaluated in sixty-six melanoma patients. Twenty out of forty-five stage I and seventeen out of twenty-one stage IIb patients presented depressed T lymphocyte values. A statistically significant increase in E-rosette-forming cells (E-RFC) was observed in seventeen (85%) stage I and twelve (70.5%) stage II patients. In thirteen (65%) stage I and eight (47%) stage II patients E-RFC reached normal values. Our results indicate that the fall of T lymphocytes in the peripheral blood of melanoma patients is often related to an increase in TP-1 sensitive cells which suggests the possibility of a thymic hormone deficiency in these patients.


Ontogeny of T cells, B cells and monocytes in the bovine foetus. The ontogeny of lymphocyte subpopulations and monocytes was studied in developing bovine foetuses. Fifty-four bovine foetuses ranging in age from 3 to 9 months of gestation were collected and examined for the presence of thymus-derived (T lymphocytes), bone marrow-derived (B lymphocytes) and phagocytic (macrophage) cells from thymus, spleen and peripheral blood. Detection of the cells expressing T lymphocyte surface markers was done using a modified sheep red blood cell rosette assay. Lymphocytes bearing surface immunoglobulin (sIg) were detected by staining with a fluoresceinated rabbit antibody prepared against bovine IgG. The procedure used for detecting monocytes was a latex bead phagocytic assay. In the thymus, the percentage of T lymphocytes was relatively constant throughout gestation at approximately 60-70%, with B lymphocytes remaining at about 1%, whereas the phagocytic cells showed an increase from 1% at 3 months to approximately 8% at term. The spleen showed an increasing percentage of T lymphocytes, from 11% at 3 months to over 40% at term, whereas the percentage of B lymphocytes remained consistent at about 2-3% from 3 months until term. The percentage of monocytes increases from 1% at 3 months to over 20% at 9 months. Peripheral blood T lymphocytes increased steadily from approximately 1% at 3 months to 45% at term. B lymphocyte levels remained low, about 1%, throughout gestation, whereas monocytes increased from 1% at 3 months to 5% at 9 months.


The significance of electrically stimulated osteogenesis: more questions than answers. The present technique of electrical osteogenesis represents the rediscovery of a method in clinical use over 100 years ago. That technique while reported to have excellent clinical results, was empirically applied and was totally discredited as having no scientific basis. Modern techniques report similarly useful clinical results, but similarly lack an accepted scientific basis. The techniques in present use differ so greatly among themselves that a common mechanism of action seems highly unlikely. Yet all report excellent clinical results. Serious questions are raised concerning the validity of the claims, the mechanism of action and the possibility of long-term undesirable side effects. These questions are not insoluble and the newer physical science disciplines seem well suited to reveal the mechanism of action. Appropriate research projects must be mounted and answers to these questions obtained before the technique is made available for wide application. The importance of this procedure far transcends orthopedic surgery and bone growth stimulation and if properly pursued, it may lead to revolutionary changes, not only in basic biology, but in the practice of clinical medicine in general.


Metabolism of p-aminobenzoic acid in the perfused livers of chronically uraemic rats. 1. Chronic renal failure was induced in rats by surgical removal of thirteen-sixteenths of renal tissue. 2. The metabolism of p-amino[14C]benzoic acid was studied in the isolated perfused livers of control and chronically uraemic rats. There was a slower rate of clearance and decreased overall metabolism of the compounds in the uraemic rats. 3. Conjugation of p-amino[14C]benzoic acid with glycine and the formation of p-aminobenzoic acid glucuronide were both significantly decreased in the uraemic rats, but there was a significant increase in acetylation of both p-aminobenzoic acid and its glycine conjugate.


Pathogenesis of bleeding colonic diverticulosis: new concepts. Diverticulosis of the colon is a common disease of the older population which develops in those people who eat highly refined carbohydrate diets free of roughage. High intraluminal pressures are created in the resultant narrowed colon which tends to push the mucosa between circular muscle bundles through oblique connective tissue clefts containing the vasa recta. Massive bleeding of the colon is most commonly due to right-sided diverticulosis. It can be explained by chronic injury to the vasa recta which lie within the submucosa of the diverticulum from the apex to the antimesenteric orifice. Rupture has been documented to occur when the wall of the artery facing the diverticulum becomes weakened by intimal fibrosis, elastic lamina fragmentation, and smooth muscle atrophy. This occurs at the dome and at the antimesenteric orifice of the diverticulum. Selective angiography is the diagnostic tool of choice. Recent advances in pharmacoagiography and and embolization promise successful treatment with lower morbidity than surgical resection.


[The importance of history-taking in the diagnosis of inflammatory-rheumatic disease: a prospective study of 100 patients (author's transl)]. In a prospective study of 100 inpatients, "history-taking diagnosis" was analysed in terms of proven probability sequence, on the basis of an extensive history-taking plan. The most likely diagnosis, as obtained by history-taking, was the same as that in the final discharge letter in 72% of cases. In only 5% did new investigations establish a diagnosis not made by history-taking. Physical examination, radiological and laboratory tests, in some cases also special investigations such as renal biopsy, proved of importance, in the first instance in establishing the diagnosis (adding to or confirming diagnostic criteria) and the choice of diagnosis (exclusion diagnosis). It is a prerequisite for a high percentage of correct diagnoses by history-taking that the examining doctor is familiar with the clinical picture of rheumatic diseases, including their epidemiology, age and sex distribution, organ involvement and pattern of joint involvement, and takes time in obtaining a good history.


Metabolic carbohydrate-labelling of glycolipids from mouse splenocytes. Mitogen-stimulated B and T cells show different labelling patterns. Splenic lymphocytes from CBA/J, AKR/A/J, BALB/c/A, C57/BL/6J, C3H/HeJ and C3H/Tif nu/nu mice and B lymphocyte or T lymphocyte preparations derived from CBA/J mouse spleen were cultivated in the presence of either concanavalin A, phytohemagglutinin, Salmonella minnesota R595 lipopolysaccharide or Proteus mirabilis soluble lipoprotein. The mitogens stimulated the incorporation of [14C]galactose into acid-insoluble cell material with the same specificity for B or T cells as that known for thymidine incorporation. The glycolipids extracted from mitogen-activated, carbohydrate-labelled B or T cells were compared by thin-layer chromatography and characteristic differences between B and T cells were noted in the ganglioside as well as in the neutral glycolipid fractions. In addition, subsets of B or T cells, namely lipopolysaccharide-responsive or lipoprotein-responsive B-cell populations or nylon-purified T cells may be recognized by characteristic neutral glycolipid bands.


T lymphocytes in cerebrospinal fluid from patients with neurological diseases. T lymphocytes were determined according to their ability to form rosettes with sheep erythrocytes, in cerebrospinal fluid (CSF) from 120 patients, and in peripheral blood from 59 patients. Normal CSF contained 74.9 +/- 9.6% T lymphocytes. Increased T lymphocyte percentage was found in CSF from patients with active multiple sclerosis (MS), and Guillain-Barré syndrome, as well as the 2 patients with retrobulbar neuritis and the 1 with subacute sclerosing panencephalitis. Patients with stable MS showed no significant change in CSF T lymphocyte percentage. CSF from patients with viral meningo-encephalitis or meningo-radiculitis had a decreased T lymphocyte percentage. This decrease was also found in the 2 patients with malignant disease and the 2 with presenile dementia. An exceptionally low CSF T cell count (5%) was found in 1 patient with cerebellar ataxia.


Antipyretic analgesics in patients on antiepileptic drug therapy. The effect of administration for three days of acetylsalicylic acid (1500 mg/day), phenylbutazone (300 mg/day), paracetamol (1500 mg/day) and tolfenamic acid (300 mg/day) on serum concentrations of phenytoin and carbamazepine were studied in a group of patients on continuous antiepileptic therapy. When measured 10 h after the last dose of the analgesics, the only significant effect was a decrease in total serum phenytoin after three days of phenylbutazone. When six patients on continuous phenytoin therapy took phenylbutazone for two weeks there was at two days an initial decrease, followed by a signficiant increase in total serum phenytoin and a concomitant increase in free phenytoin in serum. Even phenylbutazone was well tolerated by most of the patients. However, its use had to be discontinued on one patient due to obvious signs of phenytoin intoxication, with concomitant increases in the serum free and total phenytoin concentrations.


Modulation of the tonic stretch reflex by monoamines. The effects of L-DOPA and 5-HTP on the tonic stretch reflex (TSR) in the decerebrate rat were studied. L-DOPA facilitated the TSR in a dose-dependent manner. The facilitation of the TSR was blocked by pimozide. A sensitive electromygraphic (EMG) technique capable of recording single motor unit discharges was used. The EMG results suggest that gamma motoneuron sensitivity was increased to a greater degree than alpha motoneuron sensitivity during the facilitation by L-DOPA. The L-DOPA-induced facilitation persisted in animals partly depleted of 5-hydroxytryptamine (5-HT) by reserpine, p-chlorophenylalanine or 5,6-dihydroxytryptamine. 5-HTP inhibited the TSR in a dose-dependent manner. It is concluded that DA not 5-HT is the amine which normally mediates facilitation of the TSR after L-DOPA and that gamma motoneuron activation is more likely to be involved to a greater degree than alpha motoneuron activation in the neural mechanisms of the facilitation.


Aplastic anemia following infectious mononucleosis: possible immune etiology. A 17-year-old female developed severe aplastic anemia following serologically proven infectious mononucleosis. In vitro studies, using the granulocyte colony forming technique, suggested that the aplasia may have resulted from an immune mechanism. The patient's marrow grew no granulocyte colonies and caused inhibition of colony formation when mixed with normal marrows. The patient recovered fully after therapy with antithymocyte globulin and marrow cultures showed disappearance of the inhibitory effect. These observations suggest that the severe aplasia may have resulted from an aberrant immune response which followed infection by EB virus.


Thoughts about high chlorine peaks in X-ray microanalysis. In X-ray microanalysis of biological tissues, high Cl-peaks are constantly observable. Higher Cl-peaks in the tissue than in the epon environment suggest that most Cl originates from the tissue. Therefore rough regional estimations of the Cl level could be possible.


Analgesic efficacy and safety of Fenbufen following surgical removal of a lower wisdom tooth: a comparison with acetylsalicylic acid and placebo. In a double-blind clinical trial a new, non-steroidal anti-inflammatory agent with analgesic properties, Fenbufen, was compared to acetylsalicylic acid (ASA) and placebo. Six hundred (600) out-patients, following surgical removal of an impacted lower wisdom tooth, were divided into three groups and randomly given either Fenbufen (500 mg capsules), ASA (750 mg capsules), or placebo. One capsule was taken immediately after the surgical procedure, followed by another capsule every 6 hours. The duration of treatment was 24 hours. Thus, a total of 4 capsules were taken. Self-evaluation forms were provided to the patients and were returned to the investigators the following day. The results were statistically analyzed. Both Fenbufen and ASA were statistically superior (p less than or equal to 0.01) to placebo in relieving pain. A comparison of the Fenbufen and ASA groups demonstrated a statistically significant (p less than or equal to 0.05) superiority for Fenbufen in relieving pain. Also sleep was less disturbed in the Fenbufen group. Side-effects reported were few, minor in character, and fewer in number in the Fenbufen group.


Aspirin and gastrointestional bleeding. Interest of plasma salicylate determination. From history-taking and from analysis of plasma salicylate levels it is shown that a link exists between aspirin and gastrointestinal bleeding in 68% of cases. Salicylate levels alone indicate that aspirin has been taken in 22% of cases. Plasma salicylate measurement and endoscopy allow a better understanding of haemorrhagic lesions due to aspirin. Aspirin is responsible especially for haemorrhage from ulcers and acute gastritis or duodenitis. Aspirin is seen to be dangerous in a moderate number of susceptible individuals: those with peptic ulcer constitution or cirrhosis.


The management of unstable angina pectoris. Patients with unstable angina should first be medically managed with the maximally effective drug regimen. Cardiac catheterization is called for if the angina continues. Surgical intervention may be more effective if preceded by intensive medical management. You should be aware, however, that patients with unstable angina and significant left main coronary disease require immediate coronary bypass surgery.


[Enelbin rheumatism ointment in rheumatic diseases. Results of a double-blind study for the determination of efficacy]. Enelbin-Rheuma-ointment and a reference ointment were compared with regard to effectiveness in a double-blind trial in 100 patients with gonarthrosis, osteoarthrosis of the spine and humeroscapular periarthropathy. Both ointments showed good results regarding spontaneous pain, pain on pressure and motion, reduction of mobility, swelling and muscular tension. The success of treatment was statistically significantly better in the Enelbin-Rheuma-ointment treated patients.


[Immunoreactions of the delayed type in patients with multiple sclerosis (author's transl)]. Skin tests were performed in 34 multiple sclerosis patients. The incidence of positive reactions was reduced in these patients compared with healthy controls, with regard to different recall antigens with the exception of varidase, as well as the PHA and DNCB. No definite differences in reaction between patients who had been suffering from multiple sclerosis for a long time or for a short time, could be established. However, there was a certain dependence on the stage of the disease in so far as positive reactions were less frequent during the acute episode--more pronounced during the subsiding attack than at the onset of the episode--, than during the interval between two attacks. These results suggest that multiple sclerosis is primarily characterised by a weakness of cell-mediated immunity and that this weakness becomes more pronounced during the acute episode. The differences between the skin test reactions performed during the individual phases of the disease are too slight to assist in defining the acute episodes. It may be possible to identify changes in the reaction level via long-term studies.


Effects of exercise stress on parotid gland secretion. Parotid secretion of alpha-amylase and potassium (K+) was determined in young adults following intense exercise. Exercise stress led to a significant elevation in alpha-amylase and K+ secretion, indicating an activation of adrenergic receptors supplying the parotid gland. Evidence of circadian variation or adaptation over days was not found.


Growth limitation of BHK-21 cells and its relation to folate metabolism. The role of folate metabolism in growth control in monolayer and suspension cell cultures was studied in three related cell lines: BHK-21, polyoma-transformed BHK-21 (PyBHK), and an aminopterin-resistant derivative of BHK-21 (A5). BHK-21 cells had extremely low levels of dihydrofolate reductase, PyBHK had higher levels, and A5 had extremely high levels. Hypoxanthine and thymidine together, but not individually, induced BHK-21 to grow in agar, and stimulated its growth in agarose and monolayer culture. PyBHK and A5 grew spontaneously in agar, and hypoxanthine plus thymidine had little or no effect on their growth either in suspension or in monolayer cultures. We found that exogenous folinic acid, a derivative of folate metabolism that bypasses the function of dihydrofolate reductase, mimicked the growth-stimulatory effects of exogenous hypoxanthine plus thymidine BHK-21. We conclude that the growth limitation of BHK-21 in suspension culture is due, in part, to a deficiency of dihydrofolate reductase. This enzyme deficiency limits nucleoside synthesis and can be overcome by supplying end products of this pathway.


[Immunodeficiency syndromes--a new WHO report (author's transl)]. This short note is meant to point out the importance of a new WHO publication on immunodeficiency syndromes (IDS), which was prepared by an expert committee. For the classification of primary IDS, three different principles are useful, each for particular purposes. For the first time, the importance and frequency of secondary IDS are discussed as well. The original report should be read by clinical immunologists, pediatricians, internists and others interested in IDS.


The role of kallikrein in leukocyte migration inhibition. Previous studies from this department have established the presence of leukocyte migration inhibition activity in acute nonimmune inflammatory rat pleural exudates, induced by different irritants, which involved coagulation phenomenon. In the present investigation we present evidence for a role of kallikrein in the leukocyte migration inhibition phenomenon exhibited by acute pleural exudate in rates depleted of kininogens by intravenous injection of cellulose sulfate.


The nature and therapy of refractory shock. A standard experimental shock model was used to investigate the nature and treatment of refractory shock. Peripheral vasodilatation secondary to hypoxia appeared to be the primary problem in pathogenesis, such factors as myocardial or reticuloendothelial depression being of a secondary nature. Protease inhibition using aprotinin (Trasylol) was ineffective in therapy, but glucocorticoids in pharmacological dosage produced a significant improvement in cardiodynamic and oxygen metabolic factors, provided that the agent was administered early.


Inability of immune cells treated with anti-thymocyte serum to confer on hamsters resistance to cutaneous infection with Treponema pertenue. The mechanism by which hamsters acquire resistance to yaws or frambesia is poorly understood. This investigation has shown that immune lymphoid cells (spleen and lymph node) could confer on hamsters resistance to infection with Treponema pertenue. Treatment of these immune cells with a specific antithymocyte serum (ATS) inhibited the transfer of resistance. Twenty-one days after infection, recipients of immune cells treated with ATS had cutaneous lesions, in contrast to recipients of immune cells treated with normal rabbit serum. Treatment of immune cells with ATS, however, did not completely abolish resistance to treponemal infection. The weight and number of treponemes in the lymph nodes of recipients were significantly lower than those infused with normal cells treated with ATS or normal rabbit serum. The specificity of the ATS was demonstrated by its failure to inhibit functional antibody-producing cells and its high cytotoxic activity for thymocytes. These results present direct evidence that ATS-sensitive cells are involved in resistance to frambesial infection.


Measles virus-specific antibodies and immunoglobulin M antiglobulin in sera from multiple sclerosis and rheumatoid arthritis patients. When rheumatoid factor in rheumatoid arthritis and multiple sclerosis sera was titrated by the fluorescent antibody method on measles virus-infected cells, there was a marked and variable drop in titer on acetone-fixed cells as compared with unfixed cells. This was accounted for by the failure of measles virus hemolysin-inhibiting (HLI) antibody of the immunoglobulin G class to bind to acetone-fixed infected cells. It was shown by staining unfixed and acetone-fixed measles virus-infected cells that rheumatoid factor in most rheumatoid arthritis sera combined with measles virus-specific hemagglutinin-inhibiting and HLI antibodies, whereas rheumatoid factor in multiple sclerosis sera combined only with HLI antibody. Rheumatoid factor of similar specificity was also observed in normal sera and occasionally in rheumatoid arthritis sera. Both rheumatoid arthritis and multiple sclerosis sera showed almost identical increases in average titer above normal of measles virus-specific fluorescent staining immunoglobulin G and HLI antibodies.


Suppression of lymphokine production by macrophages infiltrating murine virus-induced tumors. Immune spleen cells from mice injected with murine sarcoma virus (MSV) can produce migration inhibition factor (MIF) in vitro after stimulation with intact tumor cells. We have now found that this effector function can be regulated by suppressor macrophages present in the tumor. The cells from the tumor (CfT) exert a strong suppressive effect even after treatment with anti-Thy 1.2 plus complement but lose this capacity if adherent or phagocytic cells are removed, suggesting that the macrophage is the suppressor cell. The effects of the suppressor cells were exerted on a proliferation-independent function of the lymphocytes, since MIF production, as well as its suppression, occurred even after proliferation of the lymphocytes was blocked by mitomycin-C. The implications of these findings are that macrophages can suppress some early events involved in the activation of lymphocytes by antigen and that they do so through a mechanism that does not relate to the proliferation of the cells.


Rescue of marker phenotypes: effects of BUdR sensitization, hypoxia and high LET. The survival curve of colony-forming ability of Chinese hamster wg3h cells has been compared with the dose-response curve for the expression of an active thymidine kinase (TK) gene from these cells. The TK+ phenotype was measured by hybrid colony formation after fusion of wg3h (TK+) cells with Chinese hamster A23 (TK-) cells. The TK+ survival data fitted a multi-target curve up to 3 krad of 137 Cs irradiation, when a highly resistant fraction of hybrid colonies was seen at about 1 per cent survival. The Do of TK+ survival for the multi-target region was 3.1-4.0 times greater, than that of wg3h survival, even when the Do for cell survival varied between 136 and 545 rad by 14 MeV neutrons and hypoxia respectively. This parallel modification of cell and TK+ sensitivities suggests that the lesions causing cell inactivation are of the same type as those that cause marker inactivation. Using 14 MeV neutron data the approximate target size for TK inactivation was calculated to be 0.54-0.91 per cent of the DNA content of the cell (or about one-fifth to one-tenth of a chromosome). The data support the idea that marker inactivation results primarily from damage occurring outside the marker gene. BUdR labelling of wg3h cells before irradiation caused slight toxicity (30 per cent reduction in plating efficiency) and a twofold increase in cell sensitivity. However, the sensitivity of the TK+ phenotype increases by only 30 per cent. The increased cell sensitivity thus appeared to result from synergism between increased sensitivity of DNA to strand breakage and metabolic toxicity, the latter being largely overcome by fusion with normal cells.


Effects of hyperthermia on the mouse testis and its response to X-rays, as assayed by weight loss. The effects of both hyperthermia alone and X-rays combined with hyperthermia on mouse testis have been investigated. Testis weight on heating time was observed for temperatures in the range 39.5 to 43.75 degrees C. The relationship between the reaction rate and the reciprocal of absolute temperature indicated that, over the temperature range considered, the activation energy associated with such thermal damage was (646 +/- 45) x 10(3) J mol-1. No evidence was obtained to indicate a change in slope of the Arrhenius plot over this temperature range. Finally, despite the high sensitivity of the testis to heat and X-rays, no thermal enhancement of the weight loss after irradiation was observed when thermal treatments which, if given alone would produce some observable damage, were administered immediately after irradiation.


Increased radiosensitivity of cerebral capillaries in neonatal Gunn rats as compared to Sprague-Dawley rats. The extent of petechial haemorrhages of the cerebral cortex examined between 14 hours and 4 days after X-irradiation to the head was compared in Sprague-Dawley and homozygous Gunn rats with congenital hyperbilirubinaemia. Animals 1 to 2 days old received single doses of either 250, 500 or 750 rad. By means of a special scoring scale the degree of the damage to the microvasculature was semi-quantitatively estimated. In both strains a significant difference in effect was obtained between 250 and 500 rad, but not between 500 and 750 rad. The shape of the dose-effect curve in Gunn rats was similar to that of Sprague-Dawley rats, but displaced upwards. In Gunn rats the effect of 250 rad was greater than that of 750 rad in Sprague-Dawley rats. Possible radiosensitizing mechanisms are discussed with reference to the literature and our results.


Interaction between radiation and drug damage in mammalian cells. III. The effect of adriamycin and actinomycin-D on the repair of potentially lethal radiation damage. We have studied the effects of actinomycin-D (AMD) and Adriamycin (ADRM) on the repair of radiation damage in Chinese hamster cells (V79) in plateau phase growth. Suppression of potentially lethal damage repair (PLDR) was observed in the presence of non-toxic levels of AMD and minimally toxic levels of ADRM. The suppression of PLDR by AMD persisted as long as the drug was present. Removal of AMD was followed by prompt repair of potentially lethal injury suggesting that suppression of PLDR by AMD was not accompanied by fixation of injury to a non-repairable state. On the other hand, irradiated cells exposed to ADRM eventually repair potentially lethal injury in the presence of drug after an initial delay. AMD, but not ADRM, inhibited repair of sublethal radiation damage.


Enhanced radiation damage to the erythrocyte membrane in the presence of azide and other anions. Radiation-induced potassium loss from erythrocytes and haemolysis were enhanced by the presence of azide at the time of exposure. The enhancement occurred with post-irradiation incubation at 37 or 4 degrees C, but was inhibited by formate or ethanol. Other anions, which produce radicals known to react selectively with only a few amino acids, gave rise to a similar but lesser enhancement. It is proposed that azide radicals are more effective in producing erythrocyte damage than the OH radicals from which they derive, and that the azide radical should be regarded as another selective secondary radical. The data can be used to infer differences in the mechanisms of damage leading to potassium loss or haemolysis.


Some epidemiologic aspects of psychosomatic medicine. Both surveys of physicians' practices and community studies reveal that psychomatic disorders are very prevalent in our society. In a random sample of 1,645 adults, aged seventeen to ninety-two, we found that slightly more than 50% reported at least one psychosomatic symptom "regularly" during the preceding year; 17.3% reported two or more. A profile of the symptomatic shows that they tend to be widowed, separated, or divorced; many were unemployed, retired, or disabled. Examination of associations between certain sociocultural factors and the presence of psychosomatic symptomatology disclosed that, as a group, symptomatic respondents had been neither more nor less mobile than others. Most had relatives and friends nearby but few felt they could request help from either. Most attended church but few engaged in community activities. The symptomatic group appeared to lack meaningful social support systems. The discussion focuses on possible relationships between social change, support systems, and prevalence of psychosomatic symptomatology.


Reconstruction of the slow PIII from the rod potential. Light-induced changes in K+ efflux across the photoreceptor membrane are compensated for by active uptake of K+ by a pump, which works with a time lag causing changes in [K+]o termed the KRG. From aspartate-treated bullfrog retinas we isolated the rod potential and the slow PIII, and by using them as indices of rod function and the KRG, respectively, studied relationships between the two. We conclude in support of our previous study that in rods the pump for K+ uptake works with a time lag of some 9 sec in time constant.


Membrane addition to photoreceptor outer segments: progressive reduction in the stimulatory effect of light with increased temperature. Previous studies have indicated that temperature and light regimens affect the rates of membrane addition to rod outer segments in amphibia. However, it is not known how membrane renewal responds to simultaneous alterations of these two environmental factors. In the present study, the rates of membrane addition have been assessed in adult Rana pipiens maintained in three lighting conditions (constant light, constant darkness, and cyclic light) at three different temperatures by following the displacement of a radioactive band in autoradiographs after 3H-leucine injection. At 16 degrees, 21 degrees, and 26 degrees C, constant light increases the rate of membrane addition in red rods above the rates which occur in darkness by 39%, 14%, and 9%, respectively, whereas in the green rods, the rates of increase were 41%, 22%, and 8%. This progressive reduction in the stimulatory effect of light suggest that at the higher temperatures, rod outer segment renewal is proceeding at near maximal rates and can no longer be further accelerated by light stimulation.


Freeze-fracture and scanning electron microscopy of lymphocytes: effect of different preparatory techniques on cell surface morphology. Scanning electron microscopy (SEM) of human peripheral blood lymphocytes (hPBL) processed by two different methods reveals the existence of two main types of cell: villous and smooth. Freeze-fracture of hPBL, also processed by two methods confirms the existence of these morphological types of lymphocyte. Moreover, although the stereo surface replica technique is not a suitable method for the study of hPBL surface due to the lability of the lymphocyte replicas, some smooth cells were also encountered. Qualitative and quantitative analysis of the number, size, length and distribution of microvilli show that variations in the experimental conditions for SEM affect the surface topography of hPBL, indicating the need for studies on the effects of methods of cell collection, fixation and dehydration on the surface morphology of lymphocytes.


A cytophotometric and flow cytofluorometric approach to the differentiation of T lymphocytes in the thymus. By cytophotometric and flow cytofluorometric DNA and protein determinations two main proliferating subpopulations of thymus lymphocytes with a different percentage of cells in the S phase could be distinguished. One subpopulation had a very low protein content, was cortisone sensitive and located in the cortex. Cells with comparable low protein contents were not found amongst lymphocytes of the peripheral blood. The other lymphocyte subpopulation had a higher protein content, was cortisone resistant and situated in the cortex around a group of epithelial cells and in the medulla. The protein content of these thymus lymphocytes appeared to be comparable to that of the peripheral blood lymphocytes. On the basis of the protein content per cell, it is possible to identify and isolate the more often described major subpopulation of cortisone sensitive thymus lymphocytes remaining and dying in the thymus, and the minor cortisone resistant subpopulation of thymus lymphocytes which is the source of the peripheral T lymphocyte.


Application of orthogonal functions to the spectrophotometric determination of calciferol in oily injections. The method of orthogonal functions has been applied to the rapid spectrophotometric determination of vitamin D in oily injections. The method involves saponification of the sample and extraction of the unsaponifiable matter with ether. After cautious evaporation of ether, the residue is dissolved in isopropanol and the absorbance of the solution is measured in the range 246--296 nm at 10 nm intervals. For BPC injections, the saponification step may be omitted. A suitable dilution of the sample in isopropanol is measured in the range 250.5--300.5 nm at 10 nm intervals. Accurate and precise results are obtained in both cases.


Glutamine as a feedback inhibitor of the Rhodopseudomonas sphaeroides nitrogenase system. In whole cells of Rhodopseudomonas sphaeroides, nitrogen fixation, as measured by hydrogen production and acetylene reduction, was totally inhibited by micromolar concentrations of ammonia. This inhibition could not be duplicated by glutamate or glutamine alone. The inhibition by ammonia was abolished by methionine sulfoximine, a glutamine synthetase inhibitor. Inhibition by glutamine was complete in the presence of methionine sulfone, a preferential inhibitor of glutamate synthase, presumably by permitting a rise in the glutamine pool. The results indicated that the level of the glutamine pool controlled the activity of nitrogenase. None of these effects could be duplicated with cell-free nitrogenase, indicating there is probably a mediator which responds to the glutamine pool and inhibits nitrogenase, rather than glutamine itself being a direct inhibitor.


Crossed immunoelectrophoretic analysis of chromatophore membranes from Rhodopseudomonas sphaeroides. Triton extracts of intracytoplasmic photosynthetic membranes (chromatophores) purified from Rhodopseudomonas sphaeroides were subjected to crossed immunoelectrophoresis with antiserum raised in rabbits to purified chromatophores. A total of 31 immunoprecipitates was visualized; 2 of the immunoprecipitates were identified as reduced nicotinamide adenine dinucleotide (EC 1.6.99.3) and L-lactate dehydrogenases by enzyme staining techniques. Reaction with a monospecific antiserum identified the photochemical reaction center. Photopigments were associated with a major precipitate in the pattern which was identified on the basis of immunological identity as light-harvesting bacteriochlorophyll a . protein complex. These results provide the basis for a detailed structural and functional analysis of the chromatophore membrane by crossed immunoelectrophoresis.


Purification and characterization of cytosol phosphoenolpyruvate carboxykinase from bullfrog (Rana catesbeiana) liver. Cytosol PEP carboxykinase has been purified to electrophoretic homogeneity from bullfrog liver homogenate. The enzyme is a single polypeptide chain with a molecular weight of approximately 72,000-75,000. The purified enzyme catalyzed oxaloacetate decarboxylation (nucleoside triphosphate-supported), phosphoenolpyruvate carboxylation, and an exchange reaction between oxaloacetate and [14C]HCO3-in the presence of ITP or CTP. Manganese is absolutely required for the enzyme-catalyzed phosphoenolpyruvate carboxylation, whereas it can be replaced by Mg2+ for the oxaloacetate decarboxylation and the exchange reaction. The optimal pH of each reaction is dependent on the divalent metal ion used. The dependence of the enzyme activity on Mn2+ is markedly different in the phosphoenolpyuvate carboxylation and the oxaloacetate decarboxylation reactions.


On the nature of the activating enzyme of the inactive form of delta-aminolevulinate synthetase in Rhodopseudomonas spheroides. The activating enzyme of the inactive form of Fraction I of delta-aminolevulinate (ALA) synthetase [EC 2.3.1.37] in Rhodopseudomonas (R.) spheroides was purified about 1,000-fold from an extract of R. spheroides cells grown anaerobically in the light. The purification of the activating enzyme was achieved by fractionating the 100,000 X g supernatant fraction of the crude extract with ammonium sulfate and acetone, followed by Sephadex G-200 chromatography, pyridoxamine phosphate-Sepharose 4B chromatography, and preparative gel electrophoresis. The final preparation of the activating enzyme still contained a minor contaminant (less than 20%) as judged by disc gel electrophoresis. The activating enzyme exhibited cystathionase [EC 4.4.1.1] activity throughout the purification. These two enzyme activities were not separated at all during any step of the purification. An apparently homogeneous preparation of cystathionase [EC 4.4.1.8] purified from rat liver also exhibited activating activity in the presence of L-cystine. It was concluded that the activating enzyme is a cystathionase.


Freeze-fracture evidence for the presence of cholesterol in particle-free patches of basal disks and the plasma membrane of retinal rod outer segments of mice and frogs. The freeze-fracture technique was used to examine the membranes of the photoreceptors of mice and frogs. Particle-free patches were found in the plasma membrane and basal disk membranes of the outer segments of both mice and frogs housed at room temperature, but not in frogs kept in a cold room. These patches were shown not to be artifacts of cryoprotection or fixation, and they persisted when fresh isolated outer segments were frozen by an ultrarapid method. They were also found to persist in mouse rods when retinas were incubated and subsequently fixed at temperatures up to 80 degrees C. Cholesterol was implicated as a significant component of the patches by the observation that, in the outer segments, pits, induced by treatment with the sterol-specific polyene antibiotic filipin, were present in and confined to the particle-free patches. That these lesions are not inherently limited to particle-free membrane areas was evident in the apical plasma membrane of the photoreceptor inner segments, where particles and pits were intermixed. Treatment with saponin, a surface-active agent which specifically complexes cholesterol, resulted in the disappearance of the particle-free patches. Patches were found in basal disks of both mouse and frog rods but not in older disks nearer the pigment epithelium, which indicates that changes occur in the composition of disk membranes and/or in the molecular ordering of their protein and lipid components during the early phase of their transit from the base towards the apex of the outer segment.


Detection of gap junctions between the progeny of a canine macrophage colony-forming cell in vitro. An in vitro monocyte-macrophage colony-forming cell (M-CFC) has been detected in canine bone marrow (BM). The colonies derived from these progenitor cells were similar to murine-derived M-CFC (MacVittie and Porvaznik, 1978, J. Cell Physiol. 97:305--314) colonies, since they showed a singular macrophage line of differentiation, a lag of 14--16 days before initiating colony formation, and they survived significantly longer in culture in the absence of colony-stimulating factor (CSF) than granulocyte-macrophage colony-forming cells (GM-CFC). Endotoxin (Salmonella typhosa lipopolysaccharide W)-stimulated dog serum was used as the CSF (7% vol/vol). Canine-derived M-CFC progeny were identified as macrophages on the basis of morphology, phagocytosis, and the presence of Fc receptors for IgG. Gap junctions were observed only in canine BM, M-CFC-derived colonies using freeze-fracture and lanthanum tracer techniques. They were not observed in any GM-CFC-derived colonies. The number of gap junctions observed in freeze-fracture replicas of BM, M-CFC-derived colonies (21 colonies from three different dogs) showed a significantly positive correlation (Kendall's tau = 0.70, P less than 0.001) with the size of the colony fracture plane area. Gap junctions were observed displaying hexagonal lattices of 9.3 nm +/- 0.08 (SE) particles with a center-to-center spacing of 10.4 nm +/- 1.0 (SE) on membrane P-fracture faces. On membrane E-fracture faces, highly ordered arrays of pits with 8.7 nm +/- 0.12 (SE) center-to-center spacing were observed. Arrays of both particles and pits were also observed in fracture-face breakthroughs within a gap junction. Thus, gap junctions can form in vitro between the cells of macrophage progeny of a canine M-CFC under appropriate growth conditions. The significance of this observation is that there may be a structural basis for cell-to-cell collaboration between BM macrophages and other capable cells that either pass into the tissue for modification or develop there into mature cell forms.


[Dissecting aneursym of the ascending aorta after lateral clamping for aorto-coronary by pass (author's transl)]. Four cases of dissecting aneurysm of the aorta after lateral aortic clamping for aorto-coronary bypass are described. These accidents are rare but very serious. They often occur in hypertensive patients, and sometimes an aortic wall with a low elastic fibre content is found on histology. Surgery is that of dissecting aneurysm of the ascending aorta. However the severity of these accidents should lead to routine preventive measures during all aortocoronary bypass operations, in particular aortic anastomosis of the grafts under extra-corporeal circulation.


Prenatal diagnosis of 11beta-hydroxylase deficiency congenital adrenal hyperplasia. To predict 11beta-hydroxylase deficiency congenital adrenal hyperplasia antenatally, studies were performed in urines and amniotic fluids from 2 pregnant women who had previously given birth to affected infants and whose present pregnancies also resulted in infants with the disease. Urinary tetrahydro-11-deoxycortisol [pregnane-3alpha, 17alpha, 21-triol-20-one (THS)] was abnormally elevated in the first, second, and third trimesters (maximal values, 3.5 and 0.9 mg/24 h, respectively) but was undetectable after delivery in these mothers, in 15 normal pregnancies (10--40 weeks of gestation), and in 6 heterozygote parents. Amniotic fluid levels of THS, tetrahydrocortisol [pregnane-3alpha, 11beta, 17alpha, 21-tetra-o1-20-one (THF)], tetrahydrocortisone [pregnane-3alpha, 17alpha, 21-triol-11, 20-dione (THE)] measured by RIA at 18 weeks of gestation in the first mother and at 40 weeks in the second revealed 12.5- and 8.4-fold increases in THS, respectively, but normal THF and THE levels compared to mean levels in normal pregnancies. The THS to THF plus THE ratio, which was constant throughout pregnancy in 125 normal women (mean +/- SD, 0.63 +/- 0.34) despite the variable levels of these metabolites, was significantly elevated in both patients (4.4 and 3.8, respectively). These studies indicate that prenatal diagnosis of 11beta-hydroxylase deficiency congenital adrenal hyperplasia based on hormonal measurements is feasible.


Recognition of hapten-modified cells in vitro by human T-lymphocytes. Clearer definition of the recognitive structures of human T lymphocytes for antigens will be required to elucidate the molecular basis of diseases and immunological responses induced or regulated by normal or abnormal T-cell function. For this purpose we have investigated the cellular requirements for immune responses in vitro to trinitrophenyl-conjugated peripheral blood mononuclear cells. The responding cell was characterized as a T cell on the basis of rosetting with sheep erythrocytes. T-cell recognition of hapten in proliferative responses depended upon presentation of antigen in an appropriate stimulator-cell context. Neither autologous hapten-modified erythrocytes nor T cells restimulated responses of in vitro-primed lymphocytes. Moreover, hapten-conjugated non-T cells were more effective than modified unfractionated cells in restimulating proliferative responses. Both macrophages and non-T lymphocytes effectively restimulated hapten-conjugate responses.Cell-mixing experiments indicated that the failure of haptenated T cells to stimulate proliferative responses was not because of a lack of fresh macrophages; these experiments suggested instead that T cells do not express appropriate structures necessary to present haptenic determinants in an immunogenic form. Hapten-modified T cells, however, were capable of inducing primed lymphocytes to become efficient cytotoxic effector cells, indicating that T-cell recognitive units for stimulation of proliferative and cytotoxic responses are different. These data support the concept that for induction of proliferative responses, human T cells recognize conventional antigens in association with HLA-D-region-encoded Ia-like molecules.


Cysticercosis presenting as a mass lesion at foramen of Monro. Cysticercosis is a parasitic infestation that commonly affects the central nervous system. This is a report of computed tomography findings in a patient with a noncalcified cyst causing asymmetric lateral ventricular obstruction at the foramen of Monro. The lesion was isodense and uniformly enhancing, an unusual finding possibly related to presentation early in the course of the disease. This disease should be considered in the differential diagnosis of the lesions at the foramen of Monro in patients with appropriate residence or travel history.


An intraventricular arachnoid cyst.

An intraventricular arachnoid cyst. The computed tomographic appearance and the differential diagnosis in a case of unusual congenital intraventricular arachnoid cyst are presented.


Clinical implications of color vision research. The attributes of color and the mechanisms underlying normal and defective color vision are reviewed. The clinical implications of some research efforts bearing on congenital and acquired color defects, peripheral color vision, and the influence of photostable pigments on color vision and color vision tests is presented. This presentation is intended to illustrate how selected avenues of research have contributed to our understanding of color vision and to demonstrate the clinical utility of that research.


Localization of rhodopsin in isolated, osmotically intact rod outer segment discs. Localization of rhodopsin and its position in the membrane has been the subject of numerous studies. Most recently, immunocytochemical techniques have been employed to localize the opsin component of the molecule in in situ rod outer segments. Due to the problems inherent in localization procedures (penetration and mechanical interference) we have utilized isolated, osmotically intact rod outer segment discs in this study. Specific antibodies to chromatographically pure rhodopsin were prepared and enzymatically digested to their Fab components. The univalent Fab antibodies were conjugated to horseradish peroxidase and used to label the isolated rod outer segment discs. Discs treated with anti-opsin conjugate stained uniformly and heavily on their interdisc surfaces. Reaction product was also present on the intradisc surface in a thinner but still uniformly distributed layer. Controls treated with preimmune Fab - horseradish peroxidase conjugate showed no deposition of reaction product.


Development of the sensory systems in the larval and metamorphosing European grass frog (Rana temporaria L.). It was investigated when and how the four examined sensory systems and the behaviour performances depending on them are affected by metamorphosis and whether they develop at an uniform rate from hatching up to metamorphosis. The following conclusions were reached on the basis of the results: -- The central nervous system starts to metamorphose earlier than the habitus and the viscera. -- Motor reactions based on the new capacities of the metamorphosed sensory systems only set in after metamorphosis. -- During metamorphosis the threshold of general sensitivity for the release of motor reactions is drastically raised. -- The sense of taste does not begin to function until after metamorphosis. -- The olfactory sense is the only one of the four tested systems that functions immediately after hatching. -- The level of development of the sensory systems and motor reactions is low in the early larva. The lack of taxis is characteristic of this. -- There is a phase of accelerated development of the sensory systems and motor reactions between the early and late larval stages. -- By comparison with the situation after metamorphosis the sensory systems of the old larva are fairly simple in their structure, but the motor reactions they permit are sufficient for the larva to cope with its aquatic biotope. -- Not until after the morphological structures have attained a new level of development do the relevant motor reactions show a corresponding advance.


Involvement of anti-Ig-activated serine protease in the generation of cytoplasmic factor(s) that are responsible for the transmission of Ig-receptor-mediated signals. Involvement of serine protease-activation in the generation of cytoplasmic factor(s) that induced NHP-specific protein kinase activity in nuclei in anti-Ig-stimulated cells was described. DFP or PMSF with anti-Ig inhibited the induction of cytoplasmic factor(s), whereas pretreatment of cells with DFP or PMSF without anti-Ig did not show any inhibitory effect on anti-Ig-induced generation of cytoplasmic factor(s). TAME or BAME with anti-Ig inhibited the generation of cytoplasmic factor(s) and the simultaneous addition of TAME or BAME with DFP protected the generation of cytoplasmic factor(s) against the inhibitory effect of DFP, showing the involvement of trypsin-like, arginine-type serine protease in anti-Ig-induced generation of cytoplasmic factor(s). Anti-Ig-stimulated membrane preparations induced cytoplasmic factor(s) in normal cytoplasm. The m.w. of precursor proteins present in resting B cells and active cytoplasmic factor(s) were approximately 150,000 and 45,000, respectively. These results showed that anti-Ig-activated membrane-bound serine protease split precursor proteins in resting B cells into active cytoplasmic factor(s) responsible for signal transmission.


Terminal transferase-positive human bone marrow cells exhibit the antigenic phenotype of common acute lymphoblastic leukemia. Combined immunologic assays for TdT enzyme and membrane markers show that TdT+ cells in nonleukemic human bone marrow carry ALL-associated and Ia-like antigens but no thymocyte markers or surface Ig. These cells could be precursors involved in acute lymphoblastic leukemia of the "common" or non-T, non-B type and in lymphoid blast crisis of Ph' positive chronic myeloid leukemia. A few TdT+, Ia+ cells express cytoplasmic IgM, indicating that some pre-B cells may be TdT positive.


Primary in vitro immunogenicity of liposomal model membranes in mouse spleen cell cultures. Neither 2,4-dinitrophenyl-6-N-aminocaproylphosphatidylethanolamine (DNP-Cap-PE) nor fluoresceinthiocarbamylphosphatidylethanolamine (F1-PE) induces hapten-specific plaque-forming cells (PFC) when incubated with suspensions of spleen cells from unimmunized C57BL/6J mice. However, PFC are produced after incorporation of these synthetic lipid antigens into liposomal model membranes. The in vitro response is characterized by the following: a) it is time and dose dependent; b) the frequency of IgM PFC exceeds IgG PFC; c) both nonadherent and adherent cells are required (2-mercaptoethanol can replace the requirement for adherent cells in some experiments); d) depletion of thymus-derived cells by treatment with anti-theta antiserum plus complement does not diminish the response; e) spleen cells from nude BALB/c mice also produce PFC. Thus, the essential features of the in vivo immunogenicity of DNP-Cap-PE and F1-PE sensitized liposomes, which have been previously described, can be replicated in an in vitro cell culture system.


T suppressor (TG) lymphocytes fluctuate in parallel with changes in the clinical course of patients with multiple sclerosis. Aberrant immune responses to several unrelated antigens observed in patients with multiple sclerosis have suggested faulty regulation of immunocompetent cells. Recently human T lymphocytes have been segregated into subpopulations. T lymphocytes that bear Fc receptors for IgG suppress B lymphocyte proliferation and the production of IgG. Here we report studies on the percentage of TG cells in the peripheral blood of 25 patients all of whom met stringent clinical criteria for the diagnosis of multiple sclerosis (MS). Many of these patients were followed for more than 14 months. In the total group, nine patients experienced definite acute exacerbations of disease followed by periods of remission. The mean percentages +/- 1 standard deviation of TG cells found in all MS patients during remission, 16 +/- 6 was significantly higher than the mean found in normal subjects, 12 +/- 2. In contrast, the mean found in patients experiencing an acute attack, 6 +/- 2 was significantly lower than the mean TG level of normal subjects. Moreover, when individual patients were followed through their clinical illness, levels of TG lymphocytes that were low during acute exacerbations invariably increased to relatively high levels with the onset of clinical remission.


Subfractionation of human peripheral blood lymphocytes on the basis of their surface properties by partitioning in two-polymer aqueous phase systems. Partitioning of cells in dextran-poly(ethylene glycol) aqueous-aqueous two-phase systems is a sensitive method for separating cells and for obtaining information on their surface properties. Highly purified lymphocytes were obtained by velocity sedimentation of human peripheral blood mononuclear cells and fractionated by countercurrent distribution (CCD, a multiple-step extraction procedure) in a charged two-polymer aqueous phase system. The lymphocytes remained viable after separation (order of 90%) and the E-rosetting cells responded (after adding back monocytes) to mitogens (PHA, Con A, PWM). Not only was the total lymphocyte population found to be highly heterogeneous (as evidenced by a broad and skewed distribution curve), but we were able to show that cells that rosetted with E, or had complement or Fc receptors were composed of additional subpopulations as well. The bulk of complement-receptor-bearing cells had the lowest partition coefficient (K), E-rosetting cells an intermediate K, and Fc-receptor-containing cells the highest K. The largest lymphocytes were among the subpopulation having the highest K and neither responded to T cell mitogens nor rosetted with E. Our results thus demonstrate that human peripheral blood lymphocytes can be subfractionated by CCD. The fractions are differentially enriched with lymphocyte subpopulations having characteristic surface markers and functional abilities.


In vitro heterologous cytotoxicity by T effector cells from mice immunized with Sindbis virus. An in vitro correlate of cell-mediated cross-protection among alpha-viruses was demonstrated by cytotoxicity of Sindbis-immune spleen cells from mice to both Sindbis and Semliki Forest virus (SFV)-infected target cells. This cytotoxicity was shown to be mediated by the T cell population of the spleen and was independent of the presence of macrophages or B cells. The time when the level of the lymphocyte-mediated cytotoxicity (LMC) to SFV-infected cells was maximal coincides with the time when immunity to SFV is maximal in vivo, as reported previously, and when adoptive immunity to SFV can be transferred. After one i.p. injection of Sindbis virus, the level of homologous LMC was higher than the level of heterologous LMC. However, following a second injection of Sindbis virus as immunogen, at a time when the mice are cross-protected to SFV, the heterologous LMC was considerably higher than homologous LMC. We propose that there is suppression of the effector T cells specific for Sindbis-infected cells after the second immunizing injection, probably by homologous antibody. In contrast, there appears to be an anamnestic cell-mediated response to SFV.


Suppression of adult B cell differentiation in pokeweed mitogen-stimulated cultures by Fc(IgG) receptor-negative T cells from cord blood. Unfractionated T lymphocytes from cord blood suppressed adult B cell differentiation into immunoglobulin-producing cells in pokeweed mitogen-stimulated co-culture system. Cord blood T cells were fractionated into T cells bearing Fc receptors for IgG (Tgamma cells) and T cells lacking Fc receptors for IgG(Tnon-gamma cells) by rosette formation with ox erythrocytes coated by the IgG fraction of rabbit antisera followed by Ficoll-Hypaque gradient sedimentation. T gamma cells from cord blood, even though isolated after the interaction with immune complexes, showed no suppressor activity on adult B cell differentiation, whereas Tnon-gamma cells exerted strong suppression to a similar extent to that by unfractionated cord T cells. The suppressor activity on B cell differentiation by Tnon-gamma cell as well as by unfractioned T cells from cord blood was completely abrogated by irradiation with 2000 rads. These results indicated that, contrary to suppressor function found in adult T cells, the suppressor activity in cord T cells might be exerted by a T cell subset lacking Fc receptors for IgG(Tnon-gamma cells).


Presence of T cell-associated surface antigens on murine NK cells. The expression of T cell-associated surface antigens on natural killer (NK) spleen cells of C57BL/6 mice was evaluated by cytotoxic depletion experiments with alloantisera prepared against the Thy 1, Ly 1, Ly 2, Ly 5, Ly 6, and NK 1 antigens. The NK activity of these nonimmunized spleen cells for YAC-1 leukemia cells was dramatically reduced by antisera to the Ly 5 and NK 1 antigens. Variable results were obtained with anti-Ly 6 sera--certain pools of this antiserum decreased the NK activity, whereas other pools showed only negligible effects. The NK activity of the same cell suspensions was not affected by antisera to the Thy 1, Ly 1, and Ly 2 antigens. In parallel tests the T cell-associated cell surface antigens of alloimmune T killer cells were similarly evaluated by cytotoxic depletion experiments. In this case, the activity of these cells was consistently diminished by antisera to the Thy 1, Ly 2, Ly 5, and Ly 6 antigens, but not by antisera to the Ly 1 and NK 1 antigens. On this basis it was concluded that the NK cells expressed a restricted subset of T cell-associated alloantigens and therefore may have been derived from the T cell lineage of lymphocytes.


A rapid method for generating cytotoxic effector cells in vivo. A method is described for the production of highly cytotoxic effector T lymphocytes. The cells can be raised in vivo in healthy animals in 4--5 days, thus combining the short time period of sensitization obtained in MLC or radiation GVH, without any of the attendant risks of these two methods (infection or loss of cultures or animals). DNA synthesis and blastogenesis are maximal 4 days after sensitization and are insignificant by day 6. 20--30% of the effector cells from conjugates with the sensitizing cell strain on days 4 through 7. Cytotoxicity was specific for cells of the sensitizing strain; blast cells are cytotoxic at the peak of the reaction (day 4) but small lymphocytes are cytotoxic on subsequent days.


Increased spontaneous erythrocyte rosette formation of feline lymphocytes preincubated at 37 degrees C. Preincubation of feline peripheral blood lymphocytes (PBL) in complete medium at 37 degrees C for up to 24 h resulted in as much as a 5.5-fold increase in the per cent of T cells detectable by spontaneous E rosette formation with guinea pig erythrocytes, as compared to non-preincubated PBL. Under these same conditions, the percent of B cells, detected by EAC rosette formation, remained unchanged. Preincubation with either thymosin or levamisole caused no increase in E rosettes other than that seen with complete medium alone. The preincubation-associated increase in E rosettes was temperature dependent, independent of the source of serum in the preincubation medium, not influenced by the lymphocyte isolation procedure, and not observed when feline thymocytes were tested in place of PBL. No increase in functional activity, assayed by phytomitogen-induced lymphocyte blastogenesis, was observed in preincubated as compared to non-preincubated PBL. These results suggested either a non-specific unmasking, or the differentiation and acquisition, of E receptors by feline PBL during the preincubation procedure.


Concurrent responses of peripheral blood and splenic mononuclear cells to antigenic and mitogenic stimulation in human hepatosplenic schistosomiasis. Lymphocyte reactivity and its control was assessed in human hepatosplenic schistosomiasis, a disease in which host hypersensitivity may contribute to long-term morbidity. Antigen- and mitogen-induced incorporation of [3H]thymidine was evaluated in peripheral blood and splenic mononuclear cells of 15 patients at the time of splenectomy. The response to phytohemagglutinin (PHA) was depressed in the peripheral blood of 42% and in the spleen cells of 70% of these patients. Significant stimulation was noted, however, upon culture of blood with soluble schistosome egg antigen (SEA) in 80% and of spleen cells in 100% of the patients whose respective responses to PHA were depressed. The contribution of adherent cells to the overall response of mononuclear cells was evaluated by depletion techniques. A significant and specific decrease in the response of the resulting thymus-derived (T) lymphocyte-enriched splenic mononuclear cells to SEA was noted. These studies suggest preferential preservation of the response of circulating and splenic lymphocytes to SEA despite impairment of PHA reactivity in human hepatosplenic schistosomiasis, which may be causally related to the advanced disease of this group of patients. Moreover, activity of helper adherent cells was consistently restricted to the splenic T-lymphocyte response induced by the specific antigen SEA.


Somitogenesis in amphibian embryos. I. Experimental evidence for an interaction between two temporal factors in the specification of somite pattern. Somitogenesis is described in two species of anuran amphibians, Xenopus laevis and Rana temporaria, in which the cellular mechanics of somite formation are distinctly different. Heat shocks are employed to demonstrate a wave of cellular change which precedes somite formation down the body axis. This prior wave is shown to be kinematic. It is not a propagated wave. It is a consequence of the temporal activities of the cells laid out in space, but there is no evidence that these activities depend upon an interpretation of their position. Heat shocks cause characteristic segmental abnormalities over a zone of somites which is formed several hours after the shock. Evidence from double heat shock experiments suggests that the pattern of abnormality is the result of (i) a disturbance of co-ordination between pre-somitic cells, and (ii) the time available to those cells for recovery before they are recruited into a segmental pre-pattern at the time of passage of the prior wave. It is a temporal co-ordination that is disturbed and subsequently recovered following a heat shock. This temporal co-ordination of pre-somitic cells does not depend upon position along the axis. The evidence for two physiologically independent temporal patterns of cellular processes, which interact to specify the segmental pattern of somites (their size, shape and number), gives experimental support for the theoretical account of somitogenesis proposed by Cooke & Zeeman (1976).


Suppression of IgE antibody production in SJL mice. IV. Interaction of primed and unprimed T cells. The mechanism of selective anti-hapten IgE antibody production was studied in SJL mice. Using an adoptive transfer method of spleen cells into syngeneic recipients irradiated with a sublethal dose of 600 rads, it was demonstrated that for the suppression of anti-dinitrophenyl (DNP) IgE antibody production the interaction of two subsets of T cells is necessary. DNP-primed B cells and carrier-primed T helper cells are taken from donors primed with small amounts of DNP-carrier conjugates. Without injection of other cells, high titer and persistent anti-DNP antibodies are produced in the recipients. The two subsets of T cells that are active in suppression of IgE are taken from two types of donors: one donor is immunized (hyperprimed) with larger amounts of carrier protein twice, the other is an unprimed donor. The carrier for hyperpriming the first type of donor may be unrelated to the carrier used for priming the helper T cells. To bring about anti-DNP IgE suppression it is necessary that the animals should be challenged with the same DNP-carrier conjugate used for priming the B and T helper cells. If the hyperprimed donors were immunized with a heterologous, unrelated carrier, then this heterologous unconjugated carrier must also be injected together with the homologous DNP-carrier conjugate. In these conditions, anti-DNP IgE antibody production is suppressed, but the production of anti-DNP IgG1 antibody is not diminished.


Immuno-suppressive lymphocyte factors. I. Purification of inhibitor of DNA synthesis to homogeneity. Inhibitor of DNA synthesis (IDS) is a T-lymphocyte factor, whose role in immunnoregulation might be to nonspecifically suppress the immune system especially in situations where very high, prolonged tolerogenic doses of antigens are present. We have purified IDS-contained supernates of stimulated lymphocytes to homogeneity, through isoelectric focusing and Sephadex gel chromatography. IDS has an isoelectric point of 2.73-2.75 and in its monomeric form has a mol wt of 20,000 but exists in the supernate usually as an aggregated tetrameric form. Di- and trimeric forms are also seen. All forms are biologically active. Purity was confirmed by SDS gel electrophoresis and the binding of dansyl chloride to terminal or free amino groups of proteins and peptides. We have, further confirmed that pure IDS is not cytotoxic and is probably a glycoprotein whose activity depends on an intact carbohydrate moiety.


Suppressor T-cell mechanisms in contact sensitivity. III. Apparent non-major histocompatibility complex restriction is a result of multiple sets of major histocompatibility complex-specific suppressor T cells induced by syngeneic 2,4-dinitrophenyl-modified lymphoid cells. This report has examined the mechanisms by which major histocompatibility complex (MHC) non-restricted suppressor T cells (Ts), induced by the i.v. injection of 2,4-dinitropheny (DNP)-modified, syngeneic lymphoid cells (DNP-LC), suppress the passive transfer of contact sensitivity mediated by syngeneic and allogeneic immune delayed hypersensitivity T cells (TDH). In terms of suppression of syngeneic TDH, it was found that the suppressive action of the Ts was only blocked by pretreatment with soluble syngeneic DNP-LC membrane preparations. Monomeric DNP-lysine, polymeric DNP-protein conjugates, and syngeneic TNP-LC membranes did not inhibit Ts function. Further experiments showed that inhibition of syngeneic suppression could be achieved by DNP-modified-membrane preparations that were only H-2D-region compatible with the Ts donor. Thus, Ts antigen receptors in this system specifically recognize DNP-modified H-2D-region determinants. In contrast, it was found that pretreatment os syninduced Ts with syngeneic DNP-LC membranes did not inhibit the ability to suppress allogeneic TDH. However, pretreatment of Ts with DNP-allogeneic membranes which were H-2D-end compatible to the allogeneic target TDH eliminated their ability to suppress the specific allogeneic TDH, leaving intact suppression of syngeneic or third party TDH. It is proposed that perturbation of the immune system by i.v. injection of syngeneic NDP-LC leads to the induction of a polyclonal wave of DNP-specific Ts activity. Some members of this set of Ts recognize DNP-self MHC determinants with moderate affinity and are thus specifically inhibited after pretreatment with those DNP-self determinants. Other members of this set display receptors which cross-react with high affinity with DNP-allogeneic determinants and thus suppress allogeneic TDH cells. These allosuppressive clones can thus be specifically inhibited only by pretreatment with DNP-LC membranes, MHC-compatible with the target TDH. The data are discussed in terms of current models of T-cell cross-reactivity and T-cell-receptor recognition.


Thymic reconstitution of nude F1 mice with one or both parental thymus grafts. Thymus-derived lymphocytes (T cells) have two outstanding characteristics that distinguish them from other lymphocytes: (a) they express two specificities, one for self-antigens, the major transplantation antigens (H) coded by the major histocompatibility gene complex (MHC), and a second specificity for foreign antigenic determinants. (b) T cells must undergo differentiation or maturation in the thymus (1, 2). Apparently, an important step in T-cell differentiation in the thymus is the selection of T-cells' restriction specificity for self-H. This interpretation stems from experiments with chimeras formed by lethally irradiating parental type mice and reconstituting them with F(1) stem cells: the maturing F(1) T cells expressed predominantly the restriction specificities for the recipient parental MHC type (3-8). Alternatively, adult F(1) mice that were thymectomized, lethally irradiated, reconstituted with bone marrow, and then engrafted with a parental thymus had T cells that were restricted predominantly to the thymus donors' H-2 (4-8). The present study first extends these observations to nude mice that are born without a thymus and therefore do not develop functional T cells and second, attempts to study the possibility that suppression may be responsible for the apparent influence of the radioresistant portion of the thymus on T- cell restriction specificities. We tested the immunocompetence and restriction specificities expressed by lymphocytes from F(1) nude mice reconstituted with both parental thymus grafts; our expectation was that suppression of the expression of T-cell restriction specificity should result either in complete immunoincompetence or emergence of only one of the two possible sets of restriction specificities. Nude F(1)mice that simultaneously received thymus gratis from both parents developed spleen cells restricted to both parental H-2 types. These results are compatible with the idea that the thymus' influence on T- cell restriction is via positive selection rather than by suppression.


Adherent cell function in murine T-lymphocyte antigen recognition. IV. Enhancement of murine T-cell antigen recognition by human leukocytic pyrogen. A macrophage-dependent, antigen-specific murine T-cell proliferation assay was utilized to examine the role of soluble products of murine and human adherent cells in the activation of T lymphocytes. Highly purified human leukocytic pyrogen, and  supernates from both murine and human mononuclear phagocytes-macrophages stimulated the immune T-cell proliferative response to the multideterminant antigens dinitrophenyl-ovalbumin and keyhole limpet hemocyanin. The implications of these studies and the relationship of leukocytic pyrogen to human lymphocyte-activating factor are discussed.


Lymphoid function in F1 leads to parent chimeras: lack of evidence for adaptive differentiation of B cells or antigen-presenting cells. Information was sought on whether B cells undergo abnormal differentiation in F1 leads to parent chimeras (irradiated parental-strain mice reconstituted with F1-hybrid bone marrow cells). As assessed by collaborative responses to sheep erythrocytes in vivo, three different types of T cells restricted to interaction with strain a H-2 determinants were shown to collaborate as effectively with heterologous F1 leads to b chimera B cells as with homologous F1 leads to a chimera B cells. This applied to both primed and unprimed B cells, to IgM- and IgG-antibody formation and to production of Ig allotype. Thus, unlike T cells, B cells from F1 leads to parent chimeras behaved indistinguishably from normal F1 B cells. F1 leads to parent chimeras were also examined for their capacity to present antigen to normal F1 T cells in vivo. The results suggested that the antigen-presenting cells in these chimeras were no different than in normal F1 mice. Collectively these data imply that, at least in the situation studied, raising F1 stem cells in a parental-strain environment has a marked effect on T-cell specificity but does not discernably influence the differentiation of B cells or macrophage-like cells.


alpha-Amylase assay: current state and future development. alpha-Amylase can be measured continuously with the aid of 4-nitrophenyl glucosides, especially 4-nitrophenyl maltotrioside; the large scale enzymatic synthesis of this compound seems to be possible. Another method, which does not suffer from interference by endogenous glucose, consists of the hydrolysis of maltotetraose by alpha-amylase, followed by the determination of maltose. The substrate and the auxiliary enzymes are, however, relatively expensive. Continous methods, based on the measurement of the glucose released by alpha-amylase, are more sensitive. However, they suffer from interference by blood sugar, with exception of mechanized procedures, which remove glucose by gel filtration of the sample. Moreover these methods need alpha-glucosidase, which degrades maltooligosaccharides consisting of less than seven glucose units, whereas higher polymerized substrates show slower degradation rates by amylase, and the kinetics are not easy to understand.