RESUMEN
A monoclonal antibody 1C34-5 raised against human peripheral mononuclear cells was produced. This antibody, a monoclonal IgG1. showed positive reaction with about 90% of T and B lymphocytes, monocytes. granulocytes and bone marrow cells, but negative reaction with red blood cells and platelets by indirect immunoflurorescent technique. 1C34-5 also reacted with leucocytic cell lines except a non-T non-B lymphoid line Reh but not with erythroid line K562, HeLa cells and fibroblast cells so far tested.This antibody was also assayed histologically by an indirect immunoperoxidase technique against a variety of human normal tissue frozen sections. It was found that 1C34-5 bound to all lymphoid tissues including lymph nodes, tonsil, thymus. Peyer's patches and leucocytes scattered in other tissues, but not to all non-hematopoietic tissues as well as erythropoietic foci in fetal liver. Thus. 1C34-5 appears to recognize a human leucocyte antigen specifically.