[Immunotherapy of malignant tumors with subpopulations of T lymphocytes]

During tumor growth specific suppressor cells and non-specific macrophages increase, while helper T cells decrease, preventing the production of an adequate immunological reaction. This immunosuppression can be subdued transferring specific helper cells, that contribute to the production of effector cytotoxic lymphocytes, cooperate with B lymphocytes to produce anti-tumor antibodies, and induce the accumulation of macrophages, lymphocytes, null cells and granulocytes in the tumor zone. The experiments have been done with sarcomas induced in the BN rat by Moloney virus and methylcholanthrene, respectively. It is possible that the experimental model may be applied to human tumors.