Rat cell surface antigens. II. Isolation of a minor histocompatibility antigen.

A cell surface antigen was isolated from soluble extracts of rat lymphoid cells. Molecular weight of the purified antigen was estimated by SDS gel electrophoresis to be 10 to 20,000 daltons. Physical as well as immunologic properties of this antigen do not resemble those of any known antigenic product of the major histocompatibility locus of the rat. It is therefore proposed that it is a rat minor histocompatibility antigen.