LYMPHOCYTE-TRANSFORMATION TEST (LTT) - A MODEL FOR TESTING THE CYTOKINE-INDUCED IMMUNOMODULATORY CAPACITY OF RENAL-CELL CARCINOMA

We investigated the immunomodulatory capacity of cytokines produced by renal cell carcinoma in vitro by analyzing their effects on mitogen-i nduced T-lymphocyte blast cell transformation. All of the tested 70 ce ll cultures, derived from 70 tumor areas in 33 patients, had immunomod ulatory capacity. In addition to suppression in the lymphocyte transfo rmation test (max. 44/70; 63 %) there was also superinduction (max. 37 /70; 53 %). We found no significant correlation with the stage and gra de of primary tumors. However, the suppression of mitogen-induced T-ly mphocyte blast cell transformation was significant in multifocal tumor s (0.08 % TCM, P < 0.001) and non-significant in metastatic tumors. Th e production of the assayed cytokines IL-6, IL-10, IL-11, and TGF beta 1 was variable and there was no significant correlation to the immuno modulatory capacity of the tumors.