scFv(CD33)-CD28-41BB-CD3zeta CAR-T Lentivirus

CAR-T cell therapy, a form of adoptive immunotherapy, involves isolating and extracting T lymphocytes from the body, then genetically engineering, processing, and culturing them. The expanded CAR-T cells are then infused back into the patient. This allows the T cells to accurately recognize and bind to tumor-associated antigens (TAAs) independently of the major histocompatibility complex (MHC) and achieve therapeutic efficacy by releasing perforins, granzymes, and other molecules to directly kill tumor cells. The core of this approach is the design and construction of a specific chimeric antigen receptor (CAR). CARs are modular synthetic receptors composed of four main components: an extracellular target antigen-binding domain (a single-chain variable fragment, or ScFV, consisting of an antibody''s variable light chain (VL), variable heavy chain (VH), and an intermediate linker, responsible for tumor antigen recognition); a hinge domain; a transmembrane domain (which anchors the CAR molecule to the cell membrane and provides stability); and one or more intracellular signaling domains.

Since its inception, CAR-T therapy has undergone four generations of technological evolution. First-generation CARs typically incorporate a CD3ζ intracellular signaling domain to support TCR signaling. Second-generation CARs build upon the first generation by adding a costimulatory molecule (CD28 or 4-1BB). This costimulatory molecule, coupled to the CD3ζ signaling domain, enables T cell activation and proliferation following antigen recognition by the CAR''s scFv region, thereby enhancing the survival and anti-tumor efficacy of CAR-T cells. Third-generation CARs add a second co-stimulatory domain to second-generation CARs, further enhancing CAR-T cell proliferation and therapeutic efficacy. Fourth-generation CARs co-express cytokines or chemokines, such as IL-7, IL-15, IL-18, IL-12, CCL19, and CCL22, based on second- and third-generation CARs. These can promote T cell proliferation, enhance T cell efficacy, recruit and activate more immune cells, and strengthen the anti-tumor effect of CAR-T cells.