Expectedly, rates of intratumoral T cell infection were markedly lower (T cell versus B16-TR %CD19+, p = 0.0042 for 0 Gy and p = 0.0014 for 5 Gy), highlighting the tumor selectivity of TK-deleted VV and minimizing concerns of potential CAR T cell fratricide. This evidence concerns the gene CD19 and neoplasm.