Results of a phase I clinical trial of vaccination of glioma patients withfusions of dendritic and glioma cells

Several reports of clinical trials of immunotherapy using dendritic cells h ave been published to date. In this study, we investigated the safety and c linical response of immunotherapy with fusions of dendritic and glioma cell s for the treatment of patients with malignant glioma. Eight patients with malignant glioma, ranging in age from 4 to 63 years old, participated in th is study. Dendritic cells were generated from peripheral blood. Cultured au tologous glioma cells were established from surgical specimens in each case . Fusion cells of dendritic and glioma cells were prepared with polyethylen e glycol, and the fusion efficiency ranged from 9.2 to 35.3% (mean, 21.9%). All patients received the fusion cells every three weeks for a minimum of 3, and a maximum of 7, immunizations. Fusion cells were injected intraderma lly, close to a cervical lymph node. The percentage of CD16- and CD56-posit ive cells in peripheral blood lymphocytes slightly increased after immuniza tion in 4 out of 5 cases investigated. Peripheral blood mononuclear cells w ere incubated with irradiated autologous glioma or U87MG cells and supernat ants were harvested. In 6 cases analyzed, the concentration of interferon-g amma in the supernatant increased after immunization. Clinical results show ed that there were no serious adverse effects and two partial responses. Al though the results of the phase I clinical trial of fusion cells indicated that this treatment safely induced immune responses, we were unable to esta blish a statistically significant treatment-associated response rate, due t o the limited sample population. Therefore, further evaluation of the role of adjuvant cytokines is necessary.