Autoantibodies to citrullinated proteins: ACPA.
Anti-perinuclear factor and anti-keratin antibodies have long been known to be specifically associated with rheumatoid arthritis (RA). They were first demonstrated to target various forms of (pro)filaggrin, a protein of stratified epithelia. Then, they were found to belong to a single family of autoantibodies targeting proteins that bear peptidic epitopes centered by a citrullyl residue: the anti-citrullinated protein autoantibodies (ACPA). The main targets of ACPA in the synovial tissue were demonstrated to be citrullinated forms of the a- and beta-chains of fibrin. A chronic conflict between locally produced ACPA and deposits of citrullinated fibrin is probably responsible for self-maintaining of RA synovial inflammation. Various tests for the detection of ACPA have been developed: recent ELISAs confirm their high diagnostic specificity and improve their diagnostic sensitivity. Since ACPA appear very early in the course of the disease, their detection is of major interest to identify RA among recent arthritides. Moreover, their prognostic value may lead to start early 'aggressive' treatments to prevent irreversible joint damage.
Vincent
Christian
C
"Epidermis Differentiation and Rheumatoid Autoimmunity"; UMR 5165 CNRS-Toulouse III University, IFR30 (CNRS-INSERM-Toulouse III University-CHU de Toulouse) Toulouse France.
Nogueira
Leonor
L
Clavel
Cyril
C
Sebbag
Mireille
M
Serre
Guy
G
D000818:Animals; D000974:Antibodies, Antinuclear / Q000032:analysis; D001172:Arthritis, Rheumatoid / Q000175:diagnosis / Q000266:history / Q000276:immunology; D001323:Autoantibodies / Q000032:analysis / Q000266:history; D005340:Fibrinogen / Q000276:immunology; D000091344:Filaggrin Proteins; D019084:Fluorescent Antibody Technique, Indirect; D049673:History, 20th Century; D006801:Humans; D007381:Intermediate Filament Proteins / Q000276:immunology; D010456:Peptides, Cyclic / Q000276:immunology*; D011379:Prognosis; D051381:Rats; D012217:Rheumatoid Factor / Q000032:analysis
D000974:Antibodies, Antinuclear; D001323:Autoantibodies; C000717249:FLG protein, human; D000091344:Filaggrin Proteins; D007381:Intermediate Filament Proteins; D010456:Peptides, Cyclic; C487763:cyclic citrullinated peptide; D005340:Fibrinogen; D012217:Rheumatoid Factor