Evaluation of Lymphocytic Responses after Treatment with Bacillus Calmette-Guerin and Interferon-α 2b for Superficial Bladder Cancer

Bladder wash-derived lymphocytes from superficial bladder cancer patients involved in high dose BCG, low dose BCG, and low dose BCG with IFN-α treatments were examined. We found an increasing trend in the percentage of CD3 T cells with each weekly intravesical instillation and the proportion of CD3 T cells expressing the γδ T cell receptor was significantly higher in patients receiving standard dose BCG than those receiving low dose BCG or low dose BCG plus IFN-α. Most patients had a predominance of CD4 T cells, while some had more CD8 T cells. The CD4/CD8 ratio did not vary much during the instillations. Surprisingly, both patients and normal control individuals had high percentages of CD69- and CD45RO-positive lymphocytes in the bladder wash and this was not reflected in lymphocytes from peripheral blood collected in parallel. We found no differences in lymphocyte phenotypes, cytokine production, and clinical outcome in the patients from three arms. This may reflect that the qualitative and quantitative immune responses elicited from the three treatments are similar. However, the lymphokine-activated killing ability of peripheral blood lymphocytes against allogeneic cell-lines from the cancer patients was depressed compared to normal individuals and the cytotoxicity appeared to be enhanced after intravesical treatment.