Morphological Changes in Transplanted Solid Ehrlich Tumor of Mice after Transfer of Stimulated Spleen Cells

Spleen cells from mice bearing solid Ehrlich tumor stimu-lated in vitro with Ehrlich-tumor extract or with PHA, IL-2 and tumor extract were transferred i.v. in mice-bearers of small transplanted Ehrlich tumor (Group I) and in tumor-free mice, followed by tumor transplantation (Group II). Morphological findings for antitumor effect were found in tumors of 42.5 % of experimental mice. Four criteria were established in this respect, including evidence for lymphocytic cytotoxity. Production of a factor inhibiting Ehrlich ascites-cell migration was found in a migration-inhibition assay from the stimulated spleen cells and spleen cells obtained from mice of Group I and II. The indirect data suggested that the transferred stimulated spleen cells (lymphocytes) propagated in lymphoid organs, particularly in the spleen of mice. Then T-cells, especially tumor-specific cytotoxic lymphocytes, migrated by circulation into the pe-riphery of the tumor nodule and influenced on tumor cells. ACTA MEDICA NAGASAKIENSIA 48: 107-116, 200