Emerging evidence is demonstrating the extent of T-cell infiltration within the tumor microenvironment has favorable prognostic and therapeutic implications. Hence, immunotherapeutic strategies that augment the T-cell signature of tumors hold promising therapeutic potential. Recently, immunotherapy based on intratumoral injection of mannan-BAM, toll-like receptor ligands and anti-CD40 antibody (MBTA) demonstrated promising potential to modulate the immune phenotype of injected tumors. The strategy promotes the phagocytosis of tumor cells to facilitate the recognition of tumor antigens and induce a tumor-specific adaptive immune response. Using a syngeneic colon carcinoma model, we demonstrate MBTA's potential to augment CD8+ T-cell tumor infiltrate when administered intratumorally or subcutaneously as part of a whole tumor cell vaccine. Both immunotherapeutic strategies proved effective at controlling tumor growth, prolonged survival and induced immunological memory against the parental cell line. Collectively, our investigation demonstrates MBTA's potential to trigger a potent anti-tumor immune response.
Keywords: TLR; adjuvant; immunogenic tumor cell vaccine; irradiation.