The expression of theta-like antigen by rat peripheral lymphocytes: serologic and functional studies.
AKR/Cum mice (Thy-1b = thetaC3H) immunized with nucleated cells from WF rat thymus, Peyer's patches, peritoneal exudate, mesenteric lymph nodes, blood, bone marrow, or spleen produced antibodies cytotoxic for ADR/J  (Thy-1a = thetaAKR) but not for AKR/Cum thymocytes. The specificity of these antibodies for the Thy-1.1 (theta-AKR) antigen was confirmed by tests using thymocytes from backcross mice segregating at the Thy-1 locus. This result suggested that the rat lymphocyte antgen cross-reactive with Thy-1.1 was expressed by at least some members of each of the rat lymphoid cell populations tested. AKR/Cum mice immunized with killed rat cells also produced anti-Thy-1.1 antibodies; thus indicating that further differentiation of the injected cells was not a prerequisite for the anti-Thy-1.1 response. Unexpectedly, about 9% of unimmunized adult AKR/Cum males were found to be producing antibodies against Thy-1.1. To our knowledge, natural antibodies of this specificity have not been previously reported. Finally, it was found that peritoneal exudate cells taken from WF rats previously immunized with EL-4 mouse leukemia cells were neither killed nor functionally inactivated by treatment with anti-Thy-1.1 antibodies and complement.
D000818:Animals; D000918:Antibody Specificity; D000937:Antigen-Antibody Reactions; D000941:Antigens / Q000032:analysis*; D000961:Antilymphocyte Serum / Q000302:isolation & purification; D001202:Ascitic Fluid / Q000276:immunology; D001853:Bone Marrow / Q000276:immunology; D001854:Bone Marrow Cells; D002860:Chromium Radioisotopes; D003165:Complement System Proteins; D003601:Cytotoxicity Tests, Immunologic; D007111:Immunity, Cellular; D007115:Immunization Schedule; D007942:Leukemia, Experimental / Q000276:immunology; D008214:Lymphocytes / Q000276:immunology* / Q000502:physiology*; D008221:Lymphoid Tissue / Q000276:immunology; D008297:Male; D051379:Mice; D008806:Mice, Inbred AKR; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D011817:Rabbits / Q000276:immunology; D051381:Rats; D011920:Rats, Inbred WF; D013950:Thymus Gland / Q000276:immunology*
D000941:Antigens; D000961:Antilymphocyte Serum; D002860:Chromium Radioisotopes; D003165:Complement System Proteins