Blocking activity of the serum from semiallogeneic chimaeras produced by means of cyclophosphamide.
Blocking activity of the serum from semiallogeneic chimaeras produced by the i.p. injection of cyclophosphamide, followed by the i.v. injection of 10(8) spleen cells from (CBA X C57B-L/6)F1 hybrid mice into CBA mice, was investigated. The chimaera serum was found to inhibit local GVHR when injected together with lymphocytes from CBA mice into (CBA X C57BL/6)F1 hybrid mice, but not (CBA X BALB/c)F1 hybrids. Previous absorption of the chimaera serum with C57BL/6 lymphocytes reduced its blocking activity in local GVHR. Absorption with activated CBA anti-C57BL/6 lymphocytes had no effect on blocking activity of the serum. In some experiments the chimaera serum inhibited cytotoxic activity of CBA anti-C57BL/6 and BALB/c anti-C57BL/6 lymphocytes on the corresponding target cells in vitro. Graft-versus-graft reaction of CBA thymocytes against spleen cells from (CBA X C57BL/6)F1 hybrid mice was considerably reduced when irradiated chimaeras were the recipients. Intravenous injection of the chimaera serum into the intact CBA mice did not prolong the survival of C57BL/6 skin allografts. It is concluded that the serum blocking factor is an antibody to the transplantation antigen or an antigen-antibody complex.
D000818:Animals; D000906:Antibodies; D001667:Binding, Competitive; D002678:Chimera; D003513:Cycloheximide / Q000494:pharmacology*; D003602:Cytotoxicity, Immunologic; D005260:Female; D006087:Graft vs Host Reaction; D007108:Immune Tolerance / Q000187:drug effects*; D008214:Lymphocytes / Q000276:immunology; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D016038:Skin Transplantation; D013154:Spleen / Q000276:immunology; D014184:Transplantation, Homologous
D000906:Antibodies; D003513:Cycloheximide