title: Roles of the protein tyrosine phosphatase PTPN22 in immunity and autoimmunity.
abstract: PTPN22 is a protein tyrosine phosphatase expressed by the majority of cells belonging to the innate and adaptive immune systems. Polymorphisms in PTPN22 are associated with several autoimmune diseases, such as systemic lupus erythematosus, rheumatoid arthritis and type 1 diabetes. This review discusses the role of PTPN22 in T and B cells, and its function in innate immune cells, such as monocytes, dendritic cells and NK cells. We focus particularly on the complexity that underlies the function of PTPN22 in the biological processes of the immune system; such complexity has led various research groups to produce rather conflicting data.
authors.affiliation: San Raffaele Scientific Institute, Diabetes Research Institute, Via Olgettina 58, Milan, Italy. Electronic address: fousteri.georgia@hsr.it.
authors.forename: Georgia
authors.initials: G
authors.lastname: Fousteri
authors.forename: Stamatis-Nick C
authors.initials: SN
authors.lastname: Liossis
authors.forename: Manuela
authors.initials: M
authors.lastname: Battaglia
mesh_terms: D056704:Adaptive Immunity; D000818:Animals; D001172:Arthritis, Rheumatoid / Q000201:enzymology / Q000276:immunology* / Q000473:pathology; D001402:B-Lymphocytes / Q000201:enzymology / Q000276:immunology / Q000473:pathology; D002454:Cell Differentiation; D003713:Dendritic Cells / Q000201:enzymology / Q000276:immunology / Q000473:pathology; D003922:Diabetes Mellitus, Type 1 / Q000201:enzymology / Q000276:immunology* / Q000473:pathology; D006801:Humans; D007113:Immunity, Innate; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism; D007694:Killer Cells, Natural / Q000201:enzymology / Q000276:immunology / Q000473:pathology; D008180:Lupus Erythematosus, Systemic / Q000201:enzymology / Q000276:immunology* / Q000473:pathology; D009000:Monocytes / Q000201:enzymology / Q000276:immunology / Q000473:pathology; D011110:Polymorphism, Genetic; D054596:Protein Tyrosine Phosphatase, Non-Receptor Type 22 / Q000235:genetics* / Q000378:metabolism; D013601:T-Lymphocytes / Q000201:enzymology / Q000276:immunology / Q000473:pathology
chemical_list: D007527:Isoenzymes; C516765:PTPN22 protein, human; D054596:Protein Tyrosine Phosphatase, Non-Receptor Type 22
keywords: Autoimmunity; Autoreactive cells; Genetic predisposition; Immune tolerance; PTPN22; T regulatory cells (Treg)