Interferon Effect on Cytotoxicity of Autologous Stimulated Lymphocytes from Patients with Malignant Glioma

Itoh et al. [1] demonstrated that the rIL-2-induced activated killer (AK) activity of peripheral blood lymphocytes (PBLs) was augmented when treated by recombinant inteferon γ (rIFNγ), and that the lymphocytes were also promoted in proliferation. A human brain tumor cell line (allogeneic) was used as one of the target cells for AK assay in their study. However, there has been no study of its action against autologous tumor cells. Ellis et al. [2] reported that natural killer (NK) cells, when activated by either rIFNα or γ, acquired lymphokine-activated killer (LAK) cytolytic activity and lysed NK-resistant cells. Inteferon (IFN)-induced LAK cytotoxicity reached a peak value 24h after culture with IFNα (500 units/ml) and IFNγ (1000 units/ml). The question of whether or not IFN makes LAK cells cytotoxic against autologous glioma still remains unsolved. The present study was designed to elucidate this question.