TGFB1 and neoplasm: We previously demonstrated that TGF‐β–binding CARs can be engineered to rewire Teff cells to proliferate and produce immunostimulatory cytokines in response to soluble TGF‐β, effectively inverting an immunosuppressive signaling molecule to a potent T‐cell stimulant that triggers immunosupportive functions.14 Here, we examined how this signal inversion impacts other immune cells that may be found in the tumor microenvironment.