Expression of Alien H-2 and Non-H-2 Antigens on a Murine Mammary Tumor Cell Line, MM46

Abstract

OSHIMA, H., ISHIKAWA, S., IRIE, R. and TACHIBANA, T. Expression of Alien H-2 and Non-H-2 Antigens on a Murine Mammary Tumor Cell Line, MM46. Tohoku J. exp. Med., 1987, 152 (1), 67-80 - Tumor-associated surface antigens on MM46, a transplantable ascites tumor from a spontaneous mammary carcinoma in a C3H/He mouse, were investigated. A complement-ependent microcytotoxicity test showed the expression of MM antigen, whose specificity appeared to be identical or cross-reactive with that of Ly-6.2 antigen, as reported previously. Moreover, MM46 was also found to express alien H-2 antigenic specificities, H-2.31 and H-2.28. H-2.31 represents the private specificity of the H-2K^d molecule, while H-2.28 represents a public specificity among molecules encoded by H-2K, H-2D, and H-2L loci in the majority of original H-2 haplotypes, including H-2^d, but not H-2^k, of inbred laboratory mice. The expression of MM antigen was found to be closely associated with the appearance of hypotetraploid tumor cells. These results suggest that alien H-2 and non-H-2 antigens appeared during ascites tumor cell conversion.