the mlr-blocking factors in patients ' sera may not be identical to the so-called serum nonspecific immune inhibitor factors , but was specific to , or dependent on , the use of the husbands ' lymphocytes as stimulator cells and was mediated by immunoglobulin ( antibodies ) reactive with antigens expressed on the husbands ' b lymphocytes , e.g . the mhc class ii antigens .
C0021027
immunoglobulin
C0003241
antibodies