For their initial screen, Garcia et al. used anti-CD19 Chimeric Antigen Receptor (CAR) T cells with a CD28 or 4-1BB costimulatory domain fused to a CD3ζ signaling domain (CD28z or BBz) that were transduced with vectors expressing a set of naturally occurring T cell lymphoma genes and investigated their effects on the activation of NFAT, NF-κB, and AP-1 signaling, IL-2 secretion, and PD-1 expression in vitro upon coculture with CD19-expressing K562 cells. The gene discussed is PDCD1; the disease is T-cell non-Hodgkin lymphoma.