Monolayer cell cultures as target cells for the study of lymphocyte cytotoxicity in cancer patients

Lymphocytotoxicity using S3-Hela target cells has been studied in 20 cancer patients treated with ionizing radiation (head and neck, lung and breast cancers). Monolayer cultures of Hela cells were marked with radioactive 51 Chromium and cultured with non stimulated or phytohemagglutinin (PHA) stimulated lymphocytes. This study shows a spontaneous decrease of lymphocytotoxicity in cancer patients as compared with normal subjects and an immunodepressive effect of radiotherapy. We observe a significant decrease of lymphocytotoxicity for either stimulated or non-stimulated lymphocytes at the end of radiation treatment. Moreover one month after completion of radiotherapy a possible repair of a lymphocytoxicity seems to be related with a short-term (6 months) good prognosis.