title: Fingerprinting of anti-citrullinated protein antibodies (ACPA): specificity, isotypes and subclasses.
abstract: Anti-citrullinated protein antibodies (ACPA) are a family of rheumatoid arthritis (RA)-specific autoantibodies that recognize the amino acid citrulline, resulting from the post-translational modification of arginine. Peptidyl arginine deiminase, the enzyme responsible for citrullination, is present in humans in different isoforms with different tissue distribution, enzymatic activity and target specificity; nonetheless, the number of proteins citrullinated in physiological or pathological conditions is wide, but not every citrullinated protein is a target for antibodies. In pre-RA patients the immune response to citrullinated antigens is initially restricted, expands with time and, after the onset of the disease, is relatively stable. ACPA are heterogeneous in terms of not only fine specificity but also isotype and IgG subclasses usage. This heterogeneity may be relevant for the immunopathogenesis of RA, conditioning the interaction of antibodies with complement and Fc receptors.
authors: Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy.
authors: F
authors: F
authors: Pratesi
authors: Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy.
authors: F
authors: F
authors: Panza
authors: Toscana Biomarkers Spa, Siena, Italy.
authors: I
authors: I
authors: Paolini
authors: Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy.
authors: F
authors: F
authors: Petrelli
authors: Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy.
authors: I
authors: I
authors: Puxeddu
authors: Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy.
authors: S
authors: S
authors: Casigliani-Rabl
authors: Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy.
authors: D
authors: D
authors: Ancillotti
authors: Toscana Biomarkers Spa, Siena, Italy.
authors: C
authors: C
authors: Alcaro
authors: Toscana Biomarkers Spa, Siena, Italy Department of Pharmacological Sciences, University of Florence, Florence, Italy.
authors: P
authors: P
authors: Rovero
authors: Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy Toscana Biomarkers Spa, Siena, Italy paola.migliorini@med.unipi.it.
authors: P
authors: P
authors: Migliorini
mesh_terms: D001172:Arthritis, Rheumatoid / Q000276:immunology*; D001323:Autoantibodies / Q000276:immunology*; D002956:Citrulline / Q000276:immunology*; D003167:Complement Activation; D006801:Humans; D006867:Hydrolases / Q000378:metabolism; D007074:Immunoglobulin G / Q000145:classification*; D000076342:Protein-Arginine Deiminases; D011961:Receptors, Fc / Q000276:immunology
chemical_list: D001323:Autoantibodies; D007074:Immunoglobulin G; D011961:Receptors, Fc; D002956:Citrulline; D006867:Hydrolases; D000076342:Protein-Arginine Deiminases
keywords: ACPA; PAD; Rheumatoid arthritis