To evaluate the functionality of NK-CARs, we used CD19 single-chain variable fragment (scFv) FMC63 with a Myc-tag as the extracellular (EC) domain to target CD19-positive cancer cells, which is linked to the CD8α hinge (H), transmembrane (TM) and cytoplasmic signaling domain (CYP). Here, CD8A is linked to cancer.