MOLECULAR INDIVIDUALITY OF DIFFERENT MOUSE H-2 HISTOCOMPATIBILITY SPECIFICITIES DETERMINED BY SINGLE GENOTYPES

Mouse H-2 transplantation antigens were extracted from lymphoid cells or tumour cells as an insoluble membrane fraction and were solubilized and partly purified by gel filtration. These products, obtained from six different mouse H-2 genotypes that included nearly all of the known specificities, were fractionated by diethylaminoethylion exchange ehromatography. Column eluates were monitored by inhibition of immune cytolysis in monospecific systems defining most of the different specificities. It was revealed that, in the crude soluble products, there were many different kinds of molecules that, in several instances, carried only one kind of H-2 specificity. At least 10 different molecular species could be distinguished. Instances where specificities have not yet proved to be separable included those whose presence in any phenotype appeared to be dependent upon the coexistence of others. From eluates of ion exchange columns analysed serologically, some H-2 antigens of a single phenotype could be obtained free from each other; from H-2 mice, antigen H-2.5 was prepared essentially free from H-2.8, and H-2.8 was obtained free from H-2.5. © 1969 by The Williams and Wilkins Co.