Allogeneic MHC class I expression on bystander tumor cells does not improve long-term survival of lymphoma-bearing mice.

On day 0, BALB/c mice were injected intravenously with 10⁵live A20 tumor cells. On days 1, 5, 15, and 30, tumor-bearing mice were subcutaneously vaccinated with irradiated 10⁶ A20 cells alone or together with 10⁶ allogeneic class I–positive or –negative B78H1 cells. A group of tumor-bearing mice was left unvaccinated. Mice were monitored weekly for the development of tumor. Fourteen mice were included in each group.