Updated project metadata. Glioblastoma multiforme (GBM) is a highly aggressive and malignant brain tumor with limited therapeutic options and poor prognosis. Despite current treatments, the invasive nature of GBM often leads to recurrence. A promising alternative strategy is to harness the immune system's potential against tumor cells. Our previous data showed a B-cell-based vaccine, BVax, can provide a promising therapeutic potential for GBM. In this study, we aim to characterize the antigenic reactivity of BVax-derived antibodies and evaluate their therapeutic potential. We performed immunoproteomics and functional assays in murine models and human GBM patient samples.