Glial Targets Research Articles

Antibody-dependent cellular cytotoxicity in multiple sclerosis

The blood serum of patients with multiple sclerosis (MS) was capable of recruiting autologous as well as normal mononuclear leucocytes in specific antibody-dependent cellular cytotoxicity (ADCC) of rat glial tumor CCL 107/C 6 cells. The gliotoxic ADCC activity of MS patients was significantly higher than that of normal persons and patients with other neurological diseases. MS serum alone or in combination with guinea pig complement was not cytotoxic for glial targets, and MS leucocytes alone displayed only nonspecific natural killer (NK) cell activity, which did not differ from that of normal persons. MS ADCC activity was tissuespecific for glial cells, being almost negligible for embryonic human lung fibroblasts and nonspecific for HeLa cells. Gliotoxic ADCC activity was higher in more severely disabled MS patients than in those who were less disabled. Patients with chronic progressive MS displayed the most significantly raised ADCC activity against glial cells, while patients in a stationary state had almost normal ADCC activity.

Cell-Mediated Cytotoxicity and Serum-Mediated Blocking: Evidence that Their Associated Determinants on Human Tumor Cells are Different

The preceding paper showed that patients with gliomas may have lymphocyte-mediated cytotoxic activity (LMC) directed against at least two determinants on the glioma cell surface. The present study showed that serum from patients with gliomas could block this LMC. The blocking activity, however, was specific for different determinants on the glioma cell than those to which the LMC was directed. Blocking activity was specific for tumor cells homotypic to those of the serum donor. It was effective, however, in blocking the cytotoxic activity against these cells of lymphocytes from patients with tumors either homotypic or heterotypic to that of the serum donor. Likewise, although patients with glioblastomas or melanomas had LMC against fetal glial cells, sera from such patients were unable to block the LMC against these fetal glial targets. The specificity of the blocking activity was confirmed by absorption of the sera with various normal and neoplastic cells. These studies have thus shown an immunologic functional dichotomy among different determinants on the glioma cell surface.