Expression of cell surface antigens during allogeneic response studies with monoclonal antibodies to a polymorphic marker of activated lymphocytes and HLA class I and class II antigens

The kinetics of expression of cell surface antigens were studied during allogeneic stimulation and compared to 3H-thymidine incorporation. Two markers of T cell activation identified by monoclonal antibodies (monomorphic HLA-DR and a polymorphic blastic antigen) were compared to an ubiquitous antigen (beta 2m). beta 2m (Class I) and DR (Class II) antigens showed enhanced expression on alloactivated lymphocytes while the blastic antigen was only detected on alloactivated lymphocytes from serologically positive donors. The increased expression of these antigens could distinguish positive and negative mixed lymphocyte reactions and they preceded the rise in 3H-thymidine uptake.