THE PRESENCE OF NON-H-2 HISTOCOMPATABILITY SPECIFICITIES IN PREPARATIONS OF MOUSE H-2 ANTIGENS

Abstract

Preparations of mouse H-2 histocompatibility antigens, isolated by following haemagglutination inhibitory activity, have been examined for the presence of antigeneic specificities determined by other histocompatibility loci (non H-2 antigens). Inbred mouse strains differing only at non-H-2 loci were hybridized; transfer of spleen cells from parental strain mice to the F1 hybrids did not give a graft-versus-host reaction measurable by splenomegaly. Spleen cells from parental strain donors which had previously been injected with antigen purified from cells of the second parental strain, however, gave graft-versus-host splenomegaly. This showed that non H-2 antigeneic determinants were present in the material used and were able to pre-immunize the first parental strain. The amount of antigen required to effect pre-immunization was a small fraction (about 1% on a dry weight basis) of the amount of whole cells required to produce the same effect. This suggests that substantial concentration of activity occurred on purification and that H-2 and non H-2 activity had not separated during the fractionation procedure.