[Enhanced anti-tumor effect of lymphokine-activated killer cells transfected with tumor necrosis factor-alpha gene on human glioma cells].

Tumor necrosis factor (TNF)-alpha gene were transfected into lymphokine-activated killer (LAK) cells generated from peripheral blood lymphocytes incubated with recombinant interleukin-2 by means of novel liposomes with a positive charge on their surface. The cells secreted significant amounts of TNF-alpha into the culture medium and exhibited reinforcement of cytotoxicity toward a human glioma cell line (U251-SP), being three times more cytotoxic than nontransfected LAK cells. The mechanism for the reinforcement of cytotoxicity is considered to involve not only an increase in TNF-alpha secretion from LAK cells but also its expression on their surface. Intratumoral or intrathecal injection of LAK cells transfected with the TNF-alpha gene may be useful for the treatment of patients with malignant glioma.