Serological detection of B-cell ("Ia-like") antigens in serum of normal donor and in some sera of leukaemic patients.
Some sera from normal donors (1/18) and from leukaemic patients (2/7 with acute myeloid leukaemia [AML], 1/4 with chronic lymphatic leukaemia [CLL], 0/3 with acute lymphoblastic leukaemia [ALL]; with high numbers of leukaemic cells expressing Ia-like p28,33 antigen on the leukaemic cell surface) inhibited the complement mediated cytotoxic activity of highly specific xenogenous anti Ia-like sera (which were prepared by immunization of rabbits with insoluble membrane fractions of B-type lymphoid lines) at a titre 1:4 or less. This effect was not observed with antisera directed against other membrane marker determinants (e.g. T lymphocyte specific antigens). These results suggest that at least a small proportion of membrane bound Ia-like antigens can be released from cell surfaces and in some patients these Ia-like moieties are detectable (by sensitive inhibition assays) in the serum.
D000951:Antigens, Neoplasm / Q000032:analysis*; D001402:B-Lymphocytes / Q000276:immunology*; D002460:Cell Line; D003601:Cytotoxicity Tests, Immunologic; D003602:Cytotoxicity, Immunologic; D000939:Epitopes; D006681:HLA-D Antigens; D000949:Histocompatibility Antigens Class II / Q000032:analysis*; D006801:Humans; D007938:Leukemia / Q000276:immunology*; D007945:Leukemia, Lymphoid / Q000276:immunology; D015470:Leukemia, Myeloid, Acute / Q000276:immunology
D000951:Antigens, Neoplasm; D000939:Epitopes; D006681:HLA-D Antigens; D000949:Histocompatibility Antigens Class II