Mammary tumor virus (MTV) antigens in normal and mammary tumor‐bearing mice

Abstract

Abstract Quantitative immunofluorescence tests were used to study MTV‐antigen production in normal and mammary tumor‐bearing mice of two low (BALB/c and C3Hf) and two high (C3H and GR) mammary cancer strains. Mammary tumors could be distinguished on the basis of MTV‐antigen expression in two groups; (1) a group of positive and (2) a group of negative tumors occurring in BALB/c mice. While the tumors of the first group in this study were all adenocarcinomas, the tumors of the second group were adenoacanthomas. MTV‐antigen production was comparatively high in tumors of the C3Hf and C3H strains, as well as in the MTV‐induced tumors of the BALB/c strain, but low in GR‐strain tumors. Sera from mice bearing MTV‐antigen producing mammary tumors (as well as from some pregnant and lactating GR mice) contained excess MTV‐antigens. Spleens of BALB/c mice bearing MTV‐antigen‐induced tumors often contained detectable amounts of MTV‐antigens, while normal and mammary tumor‐bearing C3Hf and C3H mice also occasionally showed detectable amounts of MTV‐antigens in their spleens. In contrast, spleens of GR mice were always MTV‐antigen negative by immunofluorescence absorption tests. Thymuses, livers and kidneys of the various strains tested were invariably negative.