CORRELATION BETWEEN EXPRESSION OF CLASS I ANTIGEN AND DEVELOPMENT OF TUMOUR INFILTRATING LYMPHOCYTES (TILS) FROM TUMOUR BIOPSIES OF PATIENTS WITH BLADDER CANCER

This report presents the findings of TIL development from tumour biopsies of patients with bladder cancer. Analysis of tissue sections showed the presence of T cells in intra-epithelial layer in 8 of 12 cases investigated. In a larger group of patients, TILs were established from 7 of 20 cases and expansion of these cells in Interleukin-2 (IL-2) in the presence of conditioned medium (CM) resulted in increase cell number to as many as 100 fold. Cell surface antigen profile of the cells showed characteristics of activated T cells and showed cytotoxic activity against tumour cell lines K256 and Daudi. In one case where TILs and tumour cell line from the same individual was established, it was found that TILs showed low levels of cytotoxicity against the autologous tumour cells. Investigation of correlation between class I antigen expression and TIL development revealed that all the 7 cases of positive TILs were established from tissue expressing normal levels of free chain of class I antigens. These results are indicative of the presence of IL-2-expandable T cells in tumour biopsy of patients with bladder cancer and demonstrate that the successful expansion of these cells correlates with the normal expression of class I antigens.