CD278

CD278 also known as Inducible T-cell COStimulator (ICOS) is a protein that in humans is encoded by the ICOS gene. ICOS is a member of the CD28 and CTLA-4 cell-surface receptor family. It is an immune checkpoint and stimulates T-cell proliferation and cytokine production.

Structure

The ICOS protein is a homodimeric protein that is a member of the immunoglobulin superfamily. It is composed of two identical chains, each containing two extracellular domains: an immunoglobulin variable (IgV) domain and an immunoglobulin constant (IgC) domain.

Function

ICOS is expressed on activated T cells and binds to its ligand, B7RP-1, on antigen-presenting cells. This interaction provides a costimulatory signal that is essential for T cell proliferation and production of IL4, IL5, and IL13. It also plays a key role in the development of follicular T helper cells (Tfh), a subset of T cells involved in the production of antibodies by B cells.

Clinical significance

Abnormal ICOS function has been associated with a number of autoimmune diseases, including rheumatoid arthritis, systemic lupus erythematosus, and multiple sclerosis. In addition, ICOS is a potential target for immunotherapy in cancer, as blocking its function can enhance the anti-tumor response of T cells.

See also

• CD28
• CTLA-4
• T-cell
• Cytokine
• Autoimmune diseases
• Immunotherapy

References

‎ ‎

---

Translate: - East Asian 中文, 日本, 한국어, South Asian हिन्दी, தமிழ், తెలుగు, Urdu, ಕನ್ನಡ, Southeast Asian Indonesian, Vietnamese, Thai, မြန်မာဘာသာ, বাংলা
European español, Deutsch, français, Greek, português do Brasil, polski, română, русский, Nederlands, norsk, svenska, suomi, Italian
Middle Eastern & African عربى, Turkish, Persian, Hebrew, Afrikaans, isiZulu, Kiswahili,
Other Bulgarian, Hungarian, Czech, Swedish, മലയാളം, मराठी, ਪੰਜਾਬੀ, ગુજરાતી, Portuguese, Ukrainian