A new target for autoantibodies in patients with rheumatoid arthritis.
Early treatment of rheumatoid arthritis (RA) with disease-modifying antirheumatic drugs can achieve a better disease outcome and reduce the severity of joint damage. The presence of autoantibodies in patient sera can precede onset of the disease and thus be predictive of the development of RA. To date, known autoantibodies in RA are positive in only 50-60% of RA patients at onset of disease and even less before the onset of any RA symptom. The aim of this study was to identify new antibodies that could be useful for the diagnosis of RA using synovial membrane proteins, which represent the best source of candidate RA autoantigens. The humoral reactivity of sera from RA patients was explored using immunoblotting on extracted proteins obtained from synovial membranes from RA after synovectomy or arthroplasty. A new target protein with a molecular weight of 26 kDa was found to be recognized by autoantibodies in RA sera. This protein was identified using MALDI-TOF mass spectrometry and two-dimensional electrophoresis as carbonic anhydrase III with a high level of confidence. In conclusion, this study demonstrates new autoantibodies in RA patients that are directed against carbonic anhydrase III. The sensitivity and specificity of these new autoantibodies for RA have to be further evaluated.
Robert-Pachot
Magali
M
Hospices Civils de Lyon, INSERM U851, Lyon-Sud Hospital, Department of Immunology, 69495 Pierre-Bénite, France.
Desbos
Agnes
A
Moreira
Annick
A
Becchi
Michel
M
Tebib
Jacques
J
Bonnin
Michel
M
Aitsiselmi
Tarik
T
Bienvenu
Jacques
J
Fabien
Nicole
N
D001172:Arthritis, Rheumatoid / Q000097:blood / Q000175:diagnosis / Q000276:immunology*; D001323:Autoantibodies / Q000097:blood / Q000276:immunology*; D001324:Autoantigens / Q000276:immunology* / Q000302:isolation & purification*; D015153:Blotting, Western; D024403:Carbonic Anhydrase III; D015180:Electrophoresis, Gel, Two-Dimensional; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013583:Synovial Membrane / Q000276:immunology*
D001323:Autoantibodies; D001324:Autoantigens; D024403:Carbonic Anhydrase III