MPPE1 and neoplasm: With the increased priming of tumor-infiltrating CAR+ and CAR− T cells6 and an impaired antitumor response in m1928z-CD40L CAR T cell-treated Batf3−/− mice (Fig. 2d), we hypothesized that m1928z-CD40L CAR T cells prime the tumor-infiltrating T cell population through the cDC1 population.