Virus Superantigen Increases Tumor Resistance Loss of Endogenous Mouse Mammary Tumor

Susceptibility to tumors induced by polyoma virus is conferred by an endogenous mouse mammary tumor virus superantigen

A dominant gene carried in certain inbred mouse strains confers susceptibility to tumors induced by polyoma virus. This gene, designated Pyvs, was defined in crosses between the highly susceptible C3H/BiDa strain and the highly resistant but H-2k-identical C57BR/cdJ strain. The resistance of C57BR/cdJ mice is overcome by irradiation, indicating an immunological basis. In F1 x C57BR/cdJ backcros...

Tumor Virus Superantigen Transcriptional Activation of Mammary Chromatin Structural Change in the Role of Ikaros, Demethylation, and Transcripts in Lymphomas of SJL/J Mice: Mammary Tumor Virus Superantigen Transcriptional Activator Initiated env Regulation of Mouse Mammary Tumor Virus

Superantigen expression is driven by both mouse mammary tumor virus long terminal repeat-associated promoters in transgenic mice.

In addition to the usual retroviral promoter, the mouse mammary tumor virus (MMTV) long terminal repeat carries a second promoter located in the U3 region. Here we show that both of these promoters are independently able to give rise to superantigen activity in transgenic mice. The ability of multiple MMTV promoters to drive superantigen expression underscores its importance in the virus life c...

Mls-1-like superantigen in the MA/MyJ mouse is encoded by a new mammary tumor provirus that is distinct from Mtv-7

Mls-1 is an endogenous superantigen that leads to in vivo deletion and in vitro stimulation of T cell receptor (TCR) V beta 6-, 7-, 8.1-, and 9-expressing cells. The MA/MyJ mouse deletes the identical set of TCR from its mature T cell repertoire; however, it does not contain Mtv-7, the murine mammary tumor provirus (MMTV), whose sag gene encodes Mls-1. Interestingly, the superantigen activity o...

B cells are essential for murine mammary tumor virus transmission, but not for presentation of endogenous superantigens

Murine mammary tumor viruses (MMTVs) are retroviruses that encode superantigens capable of stimulating T cells via superantigen-reactive T cell receptor V beta chains. MMTVs are transmitted to the suckling offspring through milk. Here we show that B cell-deficient mice foster nursed by virus-secreting mice do not transfer infectious MMTVs to their offspring. No MMTV proviruses could be detected...