Effects of bacillus Calmette-Guerin on cytotoxic activities of peripheral blood lymphocytes against human T24 lined and freshly isolated autologous urinary bladder transitional carcinoma cells in patients with urinary bladder cancer.

The effects of bacillus Calmette-Guerin (BCG) on the cytotoxic activities of peripheral blood lymphocytes against human T24 lined and freshly separated autologous urinary bladder transitional carcinoma cells in patients with urinary bladder cancer were analyzed in a 12-hour chromium 51 (51Cr) release assay. The results of this study indicate that BCG activates the tumor killing system through stimulation of effector cells and elevation of target cell susceptibility in patients with urinary bladder cancer, suggesting that BCG-augmented cytotoxicity may be oriented specifically to urinary bladder cancer cells. This could explain the remarkable clinical benefits of intravesical instillation of BCG against urinary bladder cancer.