Role of a subdominant H-2K super(d)-restricted SV40 tumor antigen cytotoxic T lymphocyte epitope in tumor rejection

• Published in: Virology (New York, N.Y.) N.Y.), 1998-05, Vol.244 (2), p.427-441
• Main Authors: Newmaster, R S, Mylin, L M, Fu, Tong-Ming, Tevethia, S S
• Format: Article
• Language: English
• ISSN: 0042-6822

SV40-transformed mKSA cells (H-2 super(d)) readily induce progressively growing tumors in adult syngeneic BALB/c mice while expressing the full complement of H-2 super(d) MHC class I antigens. BALB/c mice previously immunized with SV40, soluble SV40 T antigen, or irradiated SV40-transformed syngeneic, allogeneic, or xenogeneic cells reject an mKSA tumor challenge even though these mice have been considered low- or nonresponders to T antigen due to difficulty in demonstrating SV40 T antigen-specific CTL. We have investigated the role of H-2 super(d)-restricted CTL in the rejection of SV40 tumors in BALB/c mice. Immunization of BALB/c mice with SV40 induced T antigen-specific CTL which were largely H-2L super(d)-restricted. However, following repeated in vitro restimulation with mKSA cells, CTL emerged which recognized a subdominant H-2K super(d)-restricted epitope corresponding to T antigen residues 499-507. Immunization of BALB/c mice with a recombinant vaccinia virus expressing the T sub(499-507) epitope provided partial protection against a challenge of syngeneic mKSA tumor cells and induced the generation of T sub(499-507)-specific CTL. These results indicate that a subdominant H-2K super(d)-restricted CTL epitope can participate in the rejection of SV40 tumors in BALB/c mice.