CD8A and atrial fibrillation: This newly developed construct has several major advantages in its design and mode of action compared with published AF-reactive CAR T-cell products (14, –, 16): (i) unlike Dectin-1 CAR T cells that have weak affinity to mature mycelium, our present product was designed to efficiently target mature AF hyphae; (ii) the spacer domain of the newly developed AF-CAR has been derived from the alpha chain of CD8, which was shown to increase CAR persistence in the circulation (28).