CD19 and acute lymphoblastic leukemia: The success of CAR T-cells therapy in cancer is exemplified by the FDA-approved anti-CD19 CAR T-cell products, namely, tisagenelcleucel/Kymriah, (Novartis) for the treatment of acute lymphoblastic leukemia (ALL) and axicabtagene ciloleucel/Yescarta, (Gilead/Kite) for diffuse large B-cell lymphoma (DLBCL).