title: Role of regulatory T cells in rheumatoid arthritis: facts and hypothesis.
abstract: Regulatory T cells (Treg) are a CD4(+) lymphocyte subset involved in self-tolerance and autoimmunity prevention. There is evidence for a phenotypic and/or functional impairment of this cell subset during the natural history of several chronic autoimmune/inflammatory diseases, including rheumatoid arthritis (RA). Although the intracellular transcription factor FoxP3 is thought to be the master regulator of Treg cell function, a number of other molecules expressed on the cell surface have been proposed for the identification of Treg cells. This is important in order to favour their possible selective isolation and in the development of new therapeutic strategies. In the present paper, available data on phenotypic and functional characterization of Treg cells in both peripheral blood and synovial fluid from RA patients are reviewed and their possible pathogenic role in triggering and perpetuating rheumatoid joint inflammation is discussed.
authors.affiliation: Rheumatology Unit, Department of Clinical and Experimental Medicine, University of Perugia, via E. dal Pozzo, Perugia, I-06122 Italy.
authors.forename: Alessia
authors.initials: A
authors.lastname: Alunno
authors.affiliation: Rheumatology Unit, Department of Clinical and Experimental Medicine, University of Perugia, via E. dal Pozzo, Perugia, I-06122 Italy.
authors.forename: Elena
authors.initials: E
authors.lastname: Bartoloni
authors.affiliation: Section of Pharmacology, Toxicology and Chemotherapy, Department of Clinical and Experimental Medicine, University of Perugia, I-06122 Perugia, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Nocentini
authors.affiliation: Rheumatology Unit, Department of Clinical and Experimental Medicine, University of Perugia, via E. dal Pozzo, Perugia, I-06122 Italy.
authors.forename: Onelia
authors.initials: O
authors.lastname: Bistoni
authors.affiliation: Section of Pharmacology, Toxicology and Chemotherapy, Department of Clinical and Experimental Medicine, University of Perugia, I-06122 Perugia, Italy.
authors.forename: Simona
authors.initials: S
authors.lastname: Ronchetti
authors.affiliation: Section of Pharmacology, Toxicology and Chemotherapy, Department of Clinical and Experimental Medicine, University of Perugia, I-06122 Perugia, Italy.
authors.forename: Maria Grazia
authors.initials: MG
authors.lastname: Petrillo
authors.affiliation: Section of Pharmacology, Toxicology and Chemotherapy, Department of Clinical and Experimental Medicine, University of Perugia, I-06122 Perugia, Italy.
authors.forename: Carlo
authors.initials: C
authors.lastname: Riccardi
authors.affiliation: Rheumatology Unit, Department of Clinical and Experimental Medicine, University of Perugia, via E. dal Pozzo, Perugia, I-06122 Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Gerli
keywords: FoxP3 GITR; Rheumatoid arthritis; Treg cells