Autologous serologic responses in glioma patients. Correlation with tumor grade and survival

The serologic responses of 42 patients with gliomas have been evaluated in a quantitative microcytotoxicity assay utilizing autologous cultured glioma cells. Forty-five percent of patients had detectable cytotoxic antibody apparently directed to their own cultured cells. When tumor grade was correlated with immune response, 15/20 patients with Grade I, II and III astrocytomas had antigens detectable in autologous sera whereas only 5/22 patients with Grade IV astrocytomas had such responses. None of the autologous fibroblasts from the 15 patients with paired gliomas and fibroblast lines had membrane antigens detectable using autologous sera and fibroblast absorption did not reduce antiglioma activity. Thus, the cytotoxicity observed in this assay appears to be restricted to tumor cells, suggesting reactivity against tumor-associated antigen. In addition, it appears that these immune responses are highly correlated with survival in primary malignant brain tumor patients.