Transplantation immunity and cross-protection of two cultured murine colon lines.

Previous comparative investigations of the in vivo biology of two cultured colon tumors of BALB/c origin, C-C26 and C-C36, demonstrated different biologic activities. For elucidation of these differences, this report investigated the immunogenicity of these lines in providing protection to a subsequent challenge with different doses of tumor cells. Furthermore, the specificity of this protection was evaluated with cross-protection experiments. Our findings demonstrated these lines to be immunogenic and suggested the presence of cross-reactive tumor rejection-type antigens on these 2 cultured colon tumor lines. BALB/c mice immunized with these tumors developed resistance to challenge with the same tumor as well as to challenge with the other colon tumor lines. Further definition of these putative antigens could provide us with a better understanding for the diagnosis and treatment of colon tumors.