CD19 and neoplasm: Interestingly, Park et al, have recently demonstrated the effective use of vaccinia oncolytic virus to deliver chimeric antigen receptor (CAR) targets (truncated non-signaling variant of CD19) into solid tumors, promoting the intratumoral infiltration of both endogenous T cells and adoptively transferred CD19 CAR T cells as well as the release of intact viral progeny from dying tumor cells (Park et al, 2020).