CD4 and neoplasm: B‐cells were previously implicated as immunosuppressive within the MC38 tumor microenvironment, and removal of these cells suppressed tumor growth, suggesting the B‐cell reduction triggered by MCTN‐IRF5 treatment may impact tumor progression.[53, 54] Similarly, MCTN‐IRF5 treatment appears to reduce the TIL fraction of CD4+ T‐cells to 8.23% down from 17.4% in the control group (Figure S14B, Supporting Information).