The study of the antigenic properties of tissues and organs of animals in ontogenesis
SummaryThe antigenic properties of the tissue of developing crystalline lens of ducks was studied with the aid of anaphylactic reaction with desensitization.Morphogenesis, the rate of growth of crystalline lens and content of ribonucleic acid (RNA) in it were investigated simultaneously. It was demonstrated that during the early stages of embryogenesis (90–130 hours) the antigens are present in the tissue of developing crystalline lens, which are specific only for the definite stage of development (stage-specific antigens). There is formation and intensive growth of the primary fibers of the crystalline lens and increased concentration of the RNA during this period.
Fetuin, a New Globulin Isolated from Serum
DURING a study on the fractionation of serum with ammonium sulphate, I thought it worth while to try whether some of the serum proteins could be isolated more easily from the serum of a newly born animal. Serum from calves not more than two weeks old was used for these fractionation experiments, which immediately indicated a pronounced difference between the serum from the calf and that from the cow. Ultracentrifugal examination of the different fractions revealed the presence of large amounts of a globulin with the sedimentation constant, s20, of the order 3S (1S (Svedberg) = 1 × 10−13 C.G.S.) as compared with the normal s20 ∼ 7S for serum globulin. The main part of the new protein was precipitated between the salt concentration limits 0.37 and 0.45 saturated ammonium sulphate. It was purified further by fractionation with ammonium sulphate and centrifugation in a high-speed air-driven centrifuge. Molecular weight determination gave a value of the order 50,0001.
Presence of Fœtal Hæmoglobin in Cooley's Anæmia
COOLEY'S anæmia1 is a serious congenital disease often found among Mediterranean peoples and is associated with the appearance of red cells of uneven size and slightly distorted shape. The genetics of this disease are believed2–4 to be similar to those of sickle-cell anæmia, a Cooley's trait being carried by heterozygotes, while homozygotes show the full anæmia, usually with fatal outcome before they reach adult age.