Abstract
Comparative cytotoxic activity and specificity studies of lymphokine activated killer (LAK) cells from different sources and preparations were carried out. Cytotoxic studies of lymphocytes from regional lymph nodes (Rn-LAK), peripheral blood (Pb-LAK) and those stimulated by autologous tumor cells and then activated by recombinant interleukine 2 (St-LAK) against autologous lung cancer cells, were conducted using the 51Cr-releasing test. The cytotoxic activities of these three LAK cells against autologous fibroblasts, allogeneic tumor cells, K-562 and Daudi cells were also compared. A time course experiment disclosed that the cytotoxic activity of Pb-LAK cells against autologous tumor cells reached a maximum on day 3 and declined shortly after the peak while that of Rn-LAK cells gradually increased to a maximum on day 7 and remained at a high titer for at least two weeks. The cytotoxic activity of Rn-LAK cells was significantly higher than that of Pb-LAK cells in seven out of 10 individual experiments and that of stimulated LAK (St-LAK) cells was higher than the cytotoxic activities of the other LAK cells in eight out of nine experiments. A specificity study showed that Rn-LAK cells possessed a higher cytotoxic activity against autologous tumor cells and a lower cytotoxic activity against autologous fibroblasts and allogeneic tumor cells than Pb-LAK cells. A comparative study of cytotoxic activities against K-562, Daudi cells and autologous tumor cells between St- and Rn-LAK cells demonstrated that although there was no difference in natural killer activity, cytotoxic activity against autologous tumor cells as well as the LAK activity of St-LAK cells were higher than that of Rn-LAK cells. These results indicate that the activities and specificities of LAK cells differ according to their source and preparation.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have