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http://dx.doi.org/10.14348/molcells.2022.2056

Current Understanding of Cytotoxic T Lymphocyte Antigen-4 (CTLA-4) Signaling in T-Cell Biology and Disease Therapy  

Kim, Gil-Ran (Department of Life Science, College of Natural Sciences, Hanyang University)
Choi, Je-Min (Department of Life Science, College of Natural Sciences, Hanyang University)
Publication Information
Molecules and Cells / v.45, no.8, 2022 , pp. 513-521 More about this Journal
Abstract
Cytotoxic T lymphocyte antigen-4 (CTLA-4) is an immune checkpoint molecule that is mainly expressed on activated T cells and regulatory T (Treg) cells that inhibits T-cell activation and regulates immune homeostasis. Due to the crucial functions of CTLA-4 in T-cell biology, CTLA-4-targeted immunotherapies have been developed for autoimmune disease as well as cancers. CTLA-4 is known to compete with CD28 to interact with B7, but some studies have revealed that its downstream signaling is independent of its ligand interaction. As a signaling domain of CTLA-4, the tyrosine motif plays a role in inhibiting T-cell activation. Recently, the lysine motif has been shown to be required for the function of Treg cells, emphasizing the importance of CTLA-4 signaling. In this review, we summarize the current understanding of CTLA-4 biology and molecular signaling events and discuss strategies to target CTLA-4 signaling for immune modulation and disease therapy.
Keywords
cytotoxic T lymphocyte antigen-4 (CTLA-4); immunotherapy; signaling motif; T cell; Treg cell;
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