SV40 T antigen acts as a minor histocompatibility antigen of SV40 T antigen tolerant transgenic mice

The ability of normal mice to mount an SV40 T antigen-specific cytolytic T lymphocytes response when immunized in vivo with splenocytes from the SV40 T antigen transgenic 427-line mice and restimulated in vitro with SV40-transformed fibroblasts, or when immunized with SV40 and restimulated with 427-line splenocytes, was analyzed. Both immunization schemes resulted in an SV40 T antigen-specific immune response, indicating the presence of SV40 T antigen-positive cells in the spleens of these transgenic mice. Normal mice engrafted with skin from 427 donors showed no rejection of the graft. Thus, SV40 T antigen in transgenic 427-line mice is expressed on an undefined cell type in the spleen and acts as a tissue-specific minor histocompatibility antigen.