Cytotoxic T-cells and antibody-producing cells isolated from liver and spleen of immunized rats.

Liver, strategically positioned within the circulation system, is a major trap for circulating tumor cells. Trapping and killing of tumor cells may be mediated by Kupffer cells and natural killer cells. In addition to these spontaneously cytotoxic cells, we isolated T-killer cells and antibody-producing cells from the liver after immunization with xenogeneic cells. Since tumor surveillance may include T-killer cells and antibody-dependent killer cells, the liver is able to attack tumor cells by "natural" and "induced" cytotoxic mechanisms.