Mononuclear cell cytotoxicity in rats with Walker 256 tumor

In the present study we characterized the cytotoxicity of Wistar rat mononuclear cells from 21 animals which received 10(6) Walker 256 tumor cells by the subcutaneous route. All animals developed the tumor. Cytotoxicity was studied 15 days after inoculation using spleen, thymus and lymph node T lymphocytes as well as macrophages from the peritoneal cavity. A Walker 256 tumor cell suspension and tumor cells in culture (YAC-1) were labelled with 51Cr and used as target cells, according to the Herberman technique and a gamma counter was used for counting. Anti-Walker cell cytotoxicity was significantly decreased in T lymphocytes from the spleen (9.6% vs 51.1% for the control) and thymus (11.5% vs 38.2% for the control), whereas no difference was observed for lymph nodes (41.2% vs 49.5% for the control) or macrophages (43.4% vs 46.3% for the control). Anti-YAC-1 cytotoxicity was significantly decreased in T lymphocytes from all lymphoid organs compared to control: 23.6% vs 42.8% for the spleen, 22.6% vs 41.1% for the thymus, 26.6% vs 42.1% for lymph nodes, and 27.1% vs 46.3% for macrophages. No correlation was observed between tumor weight, and anti-Walker cytotoxicity or anti-YAC-1 cytotoxicity.