title: Reactivity of a rabbit antiserum against highly purified HLA-DR antigens.
abstract: A rabbit antiserum has been raised against highly purified, detergent-solubilized HLA-DR antigens. Externally or internally labelled surface glycoproteins from B-lymphocytes, epidermis, macrophages, and B-lymphoma cell lines reacted with the antiserum which precipitated polypeptide chains with the molecular weights 28,000 and 34,000. Such polypeptide chains were not observed when the antiserum was reacted with T-lymphocytes, T-cell lymphoma lines, kidney, brain, thymus and spermatozoa. Fab-fragments of the antiserum completely abolished the cytotoxic action of HLA-DR allantisera but had no effect on the cytotoxicity mediated by HLA-A,B and C loci antisera. Moreover, the rabbit antiserum reacted with the same molecules as the HLA-DR alloantisera. Fab-fragments of the rabbit antiserum completely abolished the MLR response and from the kinetics of the inhibition it is concluded that the Fab-fragments may interfere primarily with the initial recognition phase of the MLR.
mesh_terms: D000818:Animals; D002460:Cell Line; D002462:Cell Membrane / Q000276:immunology; D000939:Epitopes; D006680:HLA Antigens / Q000302:isolation & purification; D006801:Humans; D007106:Immune Sera; D007140:Immunoglobulin Fab Fragments; D007074:Immunoglobulin G; D007158:Immunologic Techniques; D007959:Lymphocyte Culture Test, Mixed; D008214:Lymphocytes / Q000276:immunology; D008264:Macrophages / Q000276:immunology; D011817:Rabbits; D011863:Radioimmunoassay
chemical_list: D000939:Epitopes; D006680:HLA Antigens; D007106:Immune Sera; D007140:Immunoglobulin Fab Fragments; D007074:Immunoglobulin G