title: Biological effects of IL-21 on different immune cells and its role in autoimmune diseases.
abstract: Interleukin-21 (IL-21) is a member of the common γ-chain cytokines with broad pleiotropic actions that affects different immune and nonimmune cells. IL-21 can affect differentiation, proliferation and function of T and B cells; it can also induce the maturation and enhance the cytotoxicity of CD8+ T cells and Natural killer (NK) cells. IL-21 exerts major effects on B-cell activation and differentiation or apoptosis during humoral immune responses and induces differentiation of naïve B cells and memory B cells into plasma cells. IL-21 also affects different subtypes of T cells including T helper-17 (TH17), T follicular helper (TFH) and regulatory T (Treg) cells and thereby promotes the development of autoimmune disorders and inflammatory diseases. Observations have shown that the blockade of IL-21 has therapeutic effects on various autoimmune diseases in animal models. A better understanding of the regulation of cell differentiation and stabilization by IL-21 in the context of each specific autoimmune disease or tissue-specific pathological microenvironments will be helpful in developing novel treatments to control autoimmune diseases. Herein, we review the biological effects of IL-21 on different immune cells and uncover the emerging role of this interesting cytokine in autoimmune diseases.
authors.affiliation: Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran; Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran; Department of Immunology, School of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Tohid
authors.initials: T
authors.lastname: Gharibi
authors.affiliation: Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran; Department of Immunology, School of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Jafar
authors.initials: J
authors.lastname: Majidi
authors.affiliation: Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran; Department of Immunology, School of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Tohid
authors.initials: T
authors.lastname: Kazemi
authors.affiliation: Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran; Department of Immunology, School of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Rashedeh
authors.initials: R
authors.lastname: Dehghanzadeh
authors.affiliation: Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran; Department of Immunology, School of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Morteza
authors.initials: M
authors.lastname: Motallebnezhad
authors.affiliation: Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran; Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran; Department of Immunology, School of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran. Electronic address: zbabaloo@tbzmed.ac.ir.
authors.forename: Zohreh
authors.initials: Z
authors.lastname: Babaloo
mesh_terms: D000818:Animals; D001327:Autoimmune Diseases / Q000235:genetics / Q000276:immunology* / Q000473:pathology; D016175:B-Lymphocyte Subsets / Q000187:drug effects / Q000276:immunology* / Q000473:pathology; D002454:Cell Differentiation; D002986:Clinical Trials as Topic; D003713:Dendritic Cells / Q000187:drug effects / Q000276:immunology* / Q000473:pathology; D004195:Disease Models, Animal; D005786:Gene Expression Regulation; D006801:Humans; D007155:Immunologic Factors / Q000627:therapeutic use; D007378:Interleukins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000276:immunology* / Q000494:pharmacology; D007694:Killer Cells, Natural / Q000187:drug effects / Q000276:immunology* / Q000473:pathology; D008213:Lymphocyte Activation; D010950:Plasma Cells / Q000187:drug effects / Q000276:immunology / Q000473:pathology; D006377:T-Lymphocytes, Helper-Inducer / Q000187:drug effects / Q000276:immunology* / Q000473:pathology; D050378:T-Lymphocytes, Regulatory / Q000187:drug effects / Q000276:immunology* / Q000473:pathology; D000098546:Interleukin-21
chemical_list: D007155:Immunologic Factors; D007378:Interleukins; D000098546:Interleukin-21
keywords: Autoimmune diseases; Cytokines; Interleukin-21