The influence of immunization of Syrian hamsters with tumor cells treated with glutaraldehyde on transplantation immunity and the cytotoxic effect of lymphocytes on polyoma tumor cells.

The influence of glutaraldehyde on polyoma tumor cells was studied in syngeneic Syrian hamsters, which were inoculated with glutarldhehyde-treated cells. Sera from carriers of the tumor, immunized hamsters and healthy animals inhibited in vitro cytotoxicity of sensitized lymphocytes (spleen cells) for tumor cells. If healthy animals were inoculated subcutaneously with spleen cells from immunized hamsters together with tumor cells, tumor growth was inhibited (in Winn's test) compared with animals not so inoculated and recieving only tumor cells. Cells taking part in immune responses to hamster membrane antigens were demonstrated in vitro by the microcytotoxic test. Lymphocytes from hamsters immunized with polyoma tumor cells fixed with glutaraldehyde against polyoma tumor cells were cytotoxic for target cells provided the ratio of attacking to target cells was 50:1 or higher.