CD19 and neoplasm: In addition, Chen et al. [22], through the histopathological examination of the DLBCL tumor microenvironment in patients treated with the anti-CD19 CAR-T-cell-product axicabtagene ciloleucel, demonstrated the presence of high levels of activated non-CAR-T cells expressing Ki-67, IFNγ, granzyme B, and/or PD-1.