New HLA class I-like alloantigens expressed on blast cells.
New beta 2-microglobulin (beta 2-m)-associated, HLA-linked alloantigens, selectively expressed on phytohaemagglutinin (PHA)-activated lymphocytes, were identified using human alloantisera. Reactivity of the antisera against activated cells correlated with HLA-A2, A10 and A28 specificities. The new alloantigens were undetectable on peripheral blood mononuclear cells, B lymphocytes and platelets using either the lymphocytotoxicity or the absorption techniques, and appeared on lymphocytes upon PHA activation, with time-dependent kinetics. They were found on some, but not all, acute leukaemias of B, T and myeloid origin, being absent from chronic B lymphocytic leukaemias. The presence of the new beta 2-microglobulin-associated allospecificities was not correlated with the quantity of classical class I antigens present, as analysed on different cell types by flow cytometry. Thus, these antigenic determinants appear to be different from the classical HLA class I antigens and could be the human counterpart of the murine Qa system or of the second H-2K gene.
Crepaldi
T
T
Dipartimento di Genetica, Università di Torino, Italy.
Peruccio
D
D
Lecchi
M
M
Resegotti
L
L
Grazia Guerra
M
M
Funaro
A
A
Richiardi
P
P
D001402:B-Lymphocytes / Q000276:immunology*; D005260:Female; D006680:HLA Antigens / Q000032:analysis*; D006801:Humans; D007120:Immunochemistry; D007938:Leukemia / Q000276:immunology; D008213:Lymphocyte Activation; D010835:Phytohemagglutinins / Q000494:pharmacology; D011247:Pregnancy; D013601:T-Lymphocytes / Q000276:immunology*; D001613:beta 2-Microglobulin / Q000276:immunology
D006680:HLA Antigens; D010835:Phytohemagglutinins; D001613:beta 2-Microglobulin