title: Fab2 fragments from HLA xenoantisera specifically block cytolysis mediated by HLA-AB alloantisera.
abstract: Fab2 fragments from antisera raised in rabbits with partially purified cellular and serum HLA antigens were tested for their ability to block the cytolytic activity of operationally specific HLA-A,B alloantisera. One Fab2 fragment preparation blocked the cytolytic activity of all the HLA-A,B alloantisera tested; the remaining nine inhibited the lytic activity of alloantisera to certain HLA-A,B allospecificities, suggesting that these xenoantisera contain antibody to certain HLA-A,B allotype determinants or to closely associated structures. In contrast to previous reports in the literature none of the xenoantisera contained significant amounts of antibodies to human beta 2-microglobulin.
mesh_terms: D000818:Animals; D000918:Antibody Specificity; D003429:Cross Reactions; D003601:Cytotoxicity Tests, Immunologic; D000939:Epitopes; D006680:HLA Antigens / Q000276:immunology*; D006801:Humans; D007126:Immunoglobulin Allotypes / Q000302:isolation & purification*; D007140:Immunoglobulin Fab Fragments / Q000302:isolation & purification*; D011817:Rabbits / Q000276:immunology*
chemical_list: D000939:Epitopes; D006680:HLA Antigens; D007126:Immunoglobulin Allotypes; D007140:Immunoglobulin Fab Fragments