Effect of absorbed and nonabsorbed anti-H-2 antiserum on mouse blastocysts.

Conventional antisera and monoclonal antibodies have been used to demonstrate the presence of H-2 antigens on preimplantation mouse embryos. In this study, the specificity of previously used anti-H-2 conventional antisera was tested by absorption of the antisera on spleen lymphocytes. It was found that absorption of the anti-H-2 antisera removed all of the antibody reactive with lymphocytes, but only about half of the antibody reactive with embryos. The effect of absorbed and nonabsorbed anti-H-2 antisera on mouse blastocysts was tested both by cytotoxicity assays and by electron microscopy. The results suggest that conventional antisera do indeed detect H-2 antigens on mouse embryos, but they may detect other, as yet undefined, antigens as well.