Imiquimod and Tumor Lysate Vaccine Immunotherapy in Adults With High Risk or Recurrent Grade II Gliomas

To determine the response rate and magnitude of CD8+ T-cell responses against the Imiquimod/BTIC lysate-based vaccines in post-vaccine PBMC using IFN- ELISPOT. ELISPOT assays indicate functional status of the antigen-specific T cells as cytokine-expression, and we are particularly interested in Type-1 (i.e. IFN expressing) T cell response. Therefore, IFN ELISPOT will be used as the primary assay for the immunological endpoint. Using flow-cytometry, we will also evaluate the numbers of lymphocyte subsets such as CD4+ T cells, CD4+/Foxp3+ regulatory T cells in an exploratory manner. In addition, in participants who undergo surgical debulking of the progressing tumor, if the tumor tissue is available, infiltration of antigen-specific CTLs will be evaluated by flow cytometry of tumor-infiltrating lymphocytes with the Imiquimod/BTIC lysate-based vaccine-targeted GAA specific MHC-tetramers. In addition, serological responses will be evaluated with flow-cytometry of BTIC cells as well as western blotting. These plans (in this paragraph) are immunological evaluations; however, do not compose the primary endpoints due to their exploratory nature. We will determine whether it is safe to administer Imiquimod/BTIC lysate-based vaccines in patients with grade II gliomas. Endpoints will therefore include incidence and severity of adverse events, using standard criteria as well as close clinical follow-up as would be performed normally in this group of participants following vaccinations. All reported or observed toxicities and adverse events at all clinic visits will be graded, documented and reported according to a standard toxicity table, the Common Terminology Criteria for Adverse Events (CTCAE) version 4.0