Although CAR-bearing exosomes exhibit a superior safety profile—including the absence of cytokine release syndrome (CRS) and resistance to the immunosuppressive tumor microenvironment (e.g., via the PD-1/PD-L1 axis) [69]—issues pertaining to their precise targeting, in vivo stability, and the long-term persistence of the antitumor response necessitate further investigation [53]. The gene discussed is CD274; the disease is congenital rubella syndrome.