title: Interaction of BCG-activated macrophages with neoplastic and nonneoplastic cell lines in vitro : quantitation of the cytotoxic reaction by release of tritiated thymidine from prelabeled target cells.
abstract: Peritoneal cells from mice infected ip with Mycobacterium bovis, strain BCG, were cytotoxic to syngeneic tumor cells in vitro. Cytotoxicity was estimated by measurement of release of tritiated-thymidine (3-H-TDR) from prelabeled target cells. The cell responsible for tumor cytotoxicity was the macrophage. Macrophages from uninfected mice or from oil-, starch-, or thioglycollate-induced peritoneal exudates had little effect on labeled tumor monolayers. Tumoricidal macrophages were present at 3-7 days and persisted through 6 weeks after a single BCG injection. Two neoplastic/nonneoplastic cell-line pairs, all four of the cell lines derived from a cloned syngeneic embryo cell line, were used as target cells for BCG-activated macrophages. Both tumor cell lines released significantly more 3-H-TDR than did the two nonneoplastic lines. In a mixed neoplastic/nonneoplastic target cell population, BCG-activated macrophages selectively destroyed the neoplastic cells; nonneoplastic cells were not affected as "innocent bystanders".
mesh_terms: D000818:Animals; D001202:Ascitic Fluid / Q000166:cytology; D001500:BCG Vaccine; D002460:Cell Line; D003601:Cytotoxicity Tests, Immunologic; D005122:Exudates and Transudates / Q000276:immunology; D008264:Macrophages / Q000276:immunology*; D008297:Male; D051379:Mice; D008809:Mice, Inbred C3H; D009164:Mycobacterium Infections / Q000276:immunology*; D009163:Mycobacterium bovis / Q000276:immunology*; D009369:Neoplasms / Q000276:immunology* / Q000378:metabolism; D009821:Oils; D010529:Peritoneal Cavity; D013213:Starch; D013864:Thioglycolates; D013936:Thymidine / Q000378:metabolism; D013997:Time Factors; D014316:Tritium
chemical_list: D001500:BCG Vaccine; D009821:Oils; D013864:Thioglycolates; D014316:Tritium; D013213:Starch; D013936:Thymidine