The Promise of CAR T Cell Therapy

The novel therapy of CAR T cells (Chimeric Antigen Receptor T cells) has been gaining much recognition in treating cancer along with or as an alternative to chemotherapy. They are T cells engineered with chimeric receptor proteins that increase the specificity to target a particular antigen. This artificial T cell receptor is widely used as a part of immunotherapy. The term chimeric is used because these are the fusion proteins that are made by joining two genes that originally coded for separate proteins i.e., antigen-binding gene and T cell activating function of a gene into a single receptor. CAR T cells specifically identify cancer cells and destroy them by interacting with the Tumor-Associated Antigens (TAAs) expressed on the tumor cell surface. CAR specifically binds with TAAs then T cells get activated through the phosphorylation of immune receptor tyrosine-based activation motifs (ITAMs). [1] This consequently induces T cell proliferation, cytokine secretion, and cytotoxicity. With guidance from their engineered receptor, CAR T cells multiply in the patient's body and, recognize and kill any cancer cells that harbor the target antigen on their surfaces.