Antibodies to viral citrullinated peptide in rheumatoid arthritis.
OBJECTIVE
To analyze the frequency of anti-viral citrullinated peptide (anti-VCP) antibodies in sera from patients with rheumatoid arthritis (RA) by an Epstein-Barr virus (EBV)-derived peptide in which arginine is replaced with citrulline.


METHODS
Anti-VCP antibodies were determined in 627 serum samples, 300 from patients with RA and 327 from controls, including connective tissue diseases, chronic arthritides, and healthy donors. Among patients with RA, a possible correlation with systemic involvement, disease severity, and disease activity was investigated; in 94 RA patients antibodies to cyclic citrullinated protein (anti-CCP) were also measured.


RESULTS
Anti-VCP antibodies were found in 45% of RA sera versus less than 5% of controls; anti-VCP levels correlated with anti-CCP levels (p < 0.0001), rheumatoid factor (p = 0.02), and erythrocyte sedimentation rate (p = 0.0058). No correlation was found with extraarticular manifestations of the disease or with disease severity.


CONCLUSIONS
Anti-VCP antibodies are helpful in discriminating RA from other chronic arthritides or connective tissue disorders. The level of positivity is positively correlated with the anti-CCP level, suggesting that VCP can be considered a novel substrate to detect anti-citrullinated peptide/protein antibodies (ACPA). The reactivity of RA-specific antibodies with a viral citrullinated antigen raises questions on the role of EBV in the induction of ACPA.
Anzilotti
Consuelo
C
Clinical Immunology Unit, Department of Internal Medicine, University of Pisa, Pisa, Italy.
Merlini
Giuseppina
G
Pratesi
Federico
F
Tommasi
Cristina
C
Chimenti
Daniele
D
Migliorini
Paola
P
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000974:Antibodies, Antinuclear / Q000097:blood; D000914:Antibodies, Viral / Q000276:immunology*; D001172:Arthritis, Rheumatoid / Q000276:immunology* / Q000821:virology; D020031:Epstein-Barr Virus Infections / Q000150:complications / Q000276:immunology*; D019309:Epstein-Barr Virus Nuclear Antigens / Q000737:chemistry / Q000276:immunology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010456:Peptides, Cyclic / Q000276:immunology
D000974:Antibodies, Antinuclear; D000914:Antibodies, Viral; D019309:Epstein-Barr Virus Nuclear Antigens; D010456:Peptides, Cyclic; C487763:cyclic citrullinated peptide