A dendritic cell vaccine induces protective immunity to intracranial growth of glioma.

The central nervous system is an immunologically privileged site hidden behind the blood brain barrier. Nevertheless, immune effector cells induced peripherally can be recruited into the central nervous system. Active immunotherapy of intracranial malignancies is thus potentially feasible. In this study we describe a vaccine regimen, based on bone marrow-derived dendritic cells pulsed with the RNA derived from GL261 glioma cells that induces a specific T cell response and protection against intracerebrally implanted GL261 tumors. Immunohistochemical analysis of brain tumors from vaccinated mice was characterized by pronounced intratumoral infiltrates predominantly of CD4+ as well as CD8+ T cells. The efficacy of the vaccine was improved further by administration of recombinant interleukin-12 into the vaccine regimen.