Combined Tumor Cell and Lysate-Based Vaccines for Immunotherapy of Primary and Recurrent Glioblastoma (GBM)

Glioblastoma (GBM) remains the most aggressive primary brain tumor, characterized by extensive intra-tumoral heterogeneity, profound local immunosuppression, and a highly adaptive tumor microenvironment that resists conventional therapies. Immunotherapy for GBM tries to overcome these barriers by reactivating anti-tumor immunity through cellular, molecular, and immune-modulatory interventions. The therapeutic efficacy of the cell-based vaccines in patients with glioma and glioblastoma is primarily driven by tumor antigen-specific CD8⁺ T cell activation, orchestrated by CD4⁺ T cell help. Several whole-cell vaccine platforms (e.g., DCVax-L, CMV-targeted vaccines, and Cancer Transplant Immune Recognition Therapy (CTITR)) provide personalized formulations. CTITR consists of irradiated autologous and allogeneic glioma cells and their lysates, leveraging the inherent immunogenicity of allogeneic material to bypass the need for predefined tumor-specific antigen selection. This strategy promotes broad CD8⁺ T cell expansion, potentially exceeding 10⁹ antigen-specific cytotoxic T lymphocytes, sufficient for substantial tumor clearance. Such a preparation can start with approximately 1 g of surgically resected tumor tissue per patient to generate both autologous and allogeneic vaccine components. Clinical observations indicate that cell-based vaccine preparations can be effective in both newly diagnosed glioblastoma patients treated post-surgery and in patients with recurrent gliomas. Cell-based vaccines, including CTITR, offer novel, antigen-agnostic immunotherapeutic platforms that harness autologous DC and autologous and allogeneic glioma cells, and their lysates bypass the need for predefined tumor-specific antigen selection.