ICOS+ Tregs: A Functional Subset of Tregs in Immune Diseases

• Published in: Frontiers in immunology Vol. 11; p. 2104
• Main Authors: Li, Dan-Yang, Xiong, Xian-Zhi
• Format: Journal Article
• Language: English
• Published: Switzerland Frontiers Media S.A 28.08.2020
• Subjects: Animals; autoimmune disease; Autoimmune Diseases - immunology; Autoimmune Diseases - pathology; Autoimmune Diseases - therapy; Biomarkers; Humans; ICOS; Immunology; immunotherapy; Inducible T-Cell Co-Stimulator Protein - immunology; Interleukin-10 - immunology; neoplasm; T-Lymphocytes, Regulatory - immunology; T-Lymphocytes, Regulatory - pathology; Treg cells; Treg cells; neoplasm; ICOS; autoimmune disease; immunotherapy
• ISSN: 1664-3224; 1664-3224
• DOI: 10.3389/fimmu.2020.02104

Recent studies have reported the pathological effect of ICOS + T cells, but ICOS signals also widely participate in anti-inflammatory responses, particularly ICOS + regulatory T (Treg) cells. The ICOS signaling pathway endows Tregs with increased generation, proliferation, and survival abilities. Furthermore, there is enough evidence to suggest a superior capacity of ICOS + Tregs, which is partly attributable to IL-10 induced by ICOS, yet the associated mechanism needs further investigation. In this review, we discuss the complicated role of ICOS + Tregs in several classical autoimmune diseases, allergic diseases, and cancers and investigate the related therapeutic applications in these diseases. Moreover, we identify ICOS as a potential biomarker for disease treatment and prognostic prediction. In addition, we believe that anti-ICOS/ICOSL monoclonal antibodies exhibit excellent clinical application potential. A thorough understanding of the effect of ICOS + Tregs and the holistic role of ICOS toward the immune system will help to improve the therapeutic schedule of diseases.