Inhibition of B6RV2 leukemia growth by immunization with purified unique antigen

Monoclonal antibody (mAb) NU7-99 reacted with only B6RV2 cells, not with 28 other leukemia cell lines, fibroblasts or normal tissues. Biochemical analyses of the unique antigen on B6RV2 cells that reacted with NU7-99 mAb indicated its relationship to xenotropic murine leukemia virus gp70. The antigen that reacted with NU7-99 mAb was extracted from the surface of B6RV2 cells with n-butanol and purified by ion-exchange chromatography and affinity chromatography. Growth of B6RV2 tumors in semi-syngeneic mice was inhibited by immunization of the mice with a purified preparation of this unique antigen.