CARs are receptor proteins that have been engineered to give T cells the new ability to target a specific antigen. The receptors are chimeric because they combine both antigen-binding and T cell activating functions into a single receptor. CAR T therapies are mainly used to fight cancers. The processes of CAR T-Cell therapy involves collection of patient’s immune cells from the bloodstream via apheresis. The T cells are then genetically engineering by introducing DNA into to produce CARs to recognize and attack a specific cancer-associated protein. After expansion, the CAR T cells are infused back to patient’s body. Patients may need to receive lymphodepletion chemotherapy prior to receive CAR T cells. CAR T cells may eradicate the cancer cells and may remain in the body months after the infusion for the long-term remission. The currently FDA approved CAR T cells therapies are either targeting CD19 for B cell malignancy or targeting B-cell maturation antigen (BCMA) for multiple myeloma.