THE INFLUENCE OF THE THYMIC PREPARATION THYMEX-L ON DEFICIENT ANTITUMOR-ACTIVITY OF MONOCYTES FROM MELANOMA PATIENTS IN-VITRO

Recently we demonstrated that, in vitro, prothymosin alpha 1 (ProT alp ha), a polypeptide from calf thymus, was able to enhance the deranged tumoristatic activity of peripheral blood monocytes from melanoma pati ents. Now we report, that the thymic preparation Thymex-L significantl y enhanced the level of depressed monocyte activity from 19% to 26%, w hereas in normal donor groups no significant change of basal activity (35%) was seen. Although the improvement of median levels of killer ce ll activity was found to be independent from the disease stage, the Th ymex-L effect was only statistically significant in stage I and melano ma patients after chemotherapy. In contrast to ProT alpha, Thymex-L di d not further enhance monocyte-mediated cytotoxicity when it was appli ed in combination with rIFN-gamma. However, after stimulation with rIF N-gamma, the median level of TNF-alpha secretion by melanoma monocytes significantly increased (about 2-fold) when preincubated with Thymex- L. These results indicate that depressed monocyte functions in selecte d melanoma patients may be partially improved by Thymex-L.