SUSCEPTIBILITY OF HUMAN WM MELANOMA CELL LINES TO NK AND LAK CYTOTOXICITY AND THEIR RELEVANCE TO THE LEVEL OF MHC CLASS I AND ICAM-l ANTIGEN EXPRESSION

The effect of natural killer (NK) cells and lymphokine activated killer ( LAK) cells was studied on a group of human melanoma cell lines. Peripheral blood from healthy volunteers was utilized as a fresh source of natural killer cells and rhI L-2 for producing LAK cells. The cytotoxicity of effector cells was quantified using a 4 hour SI determining the density of antigen expression on tumor cell surface. The majority of WM melanoma cell lines were relatively resistant to lysis by NK cells, but all showed high sensitivity to LAK cytotoxicity. The expression of MH C class I and I CAM-l on tumor cell lines varied, however using linear regression analysis between MH C class I and I CAM-l antigen expression, and UK/ pression of these antigens on the WM melanoma cell lines tested are independent of NK/