A study led by Cabezas‑Caballero and colleagues reports engineered co‑signaling receptors that improve T cell precision by limiting off‑target activation. The team demonstrated that redesigned receptor pairs can sharpen antigen discrimination and reduce cross‑reactivity observed with conventional engineered T cells. Authors provide mechanistic data and in vitro functional assays showing decreased activation against non‑target tissues. The work outlines a modular engineering strategy biotech developers can adopt to lower safety liabilities for next‑generation cell therapies.