REINFORCED CYTOTOXICITY OF LYMPHOKINE-ACTIVATED KILLER-CELLS TOWARD GLIOMA-CELLS BY TRANSFECTION OF THE KILLER-CELLS WITH THE GAMMA-INTERFERON GENE

Lymphokine-activated killer (LAK) cells generated from peripheral bloo d lymphocytes incubated with recombinant interleukin-2 were transfecte d with the human gamma-interferon (HuIFN-gamma) gene by means of lipos omes having a positive charge on their surface. The cells secreted sig nificant amounts of HuIFN-gamma (reaching more than 5 U/ml) into the c ulture medium. The HuIFN-gamma produced by the cells induced intercell ular adhesion molecule-1 (ICAM-1) and enhanced the expression of Fas a ntigen on the surface of human glioma cells. Also, LAK cells transfect ed with HuIFN-gamma gene exhibited reinforcement of cytotoxicity towar d human glioma cell lines (U251-MG and SK-MG-1). Furthermore, the rein forcement was significantly quenched by anti-ICAM-1 and/or anti-TNF-al pha monoclonal antibody.