CD7, also known as GP40, is a membrane-expressed protein belonging to the immunoglobulin superfamily. It is present in thymocytes and mature T cells. During early lymphocyte development, it plays an important role in T cell interactions and T cell/ B cell interactions.
(Data source: The Human Protein Atlas)
CD7 structure:
IL4 is a typical type I transmembrane protein containing two disulfide bonds and glycosylation modifications. The main functional domain is the 26-180 segment, of which 26-130 is an Ig-like domain.
(Data source Keegan AD, et al. Fac Rev. 2021)
CD7 signaling pathway and regulation:
CD7 has two ligands: K12 (SECTM1) and galectin-1. CD7 binding to K12 can enhance monocyte migration, while binding to galectin-1 can promote T cell apoptosis. Currently, the role of CD7 under normal physiological conditions remains unclear.
Clinical value of CD7:
Due to its widespread distribution on tumors, CD7 is considered a key factor in the treatment of T-cell acute lymphoblastic leukemia (TALL) and T lymphomas. Furthermore, CD7 overexpression has been observed in 30% of acute myeloid leukemias and is associated with disease progression and a worse prognosis. In 2017, anti-CD7 CAR cells were successfully generated using gene editing technology and CD7 protein blockers, which can escape the fate of fratricidal killing. This marked the feasibility of using CAR cells in clinical practice and a milestone in the research of the CD7 target. Over the next five years, a series of clinical trials, including allogeneic anti-CD7 CAR-T cells, naturally selected anti-CD7 CAR-T cells, and Phase 1 and 2 clinical trials, have been launched, achieving numerous breakthroughs in CD7 research.
(Data source Liu J, et al. Front Immunol. 2023)
For example, by destroying the donor T cell antigen CD7 through genome editing, a BE-CA7 (BE-CA7)-based T cell library is generated, allowing lentiviral-transduced CAR-T cells to specifically target CD7+ leukemia cells without killing themselves.
(Data source Chiesa R, et al. N Engl J Med. 2023)
