title: Anti-mutated citrullinated vimentin (anti-MCV) and anti-65 kDa heat shock protein (anti-hsp65): new biomarkers in ankylosing spondylitis.
abstract: BACKGROUND
  Citrullination as well as anti-citrullinated protein/peptide antibodies (ACPA) have been implicated in the pathogenesis of rheumatoid arthritis (RA). While ACPAs are specific and sensitive markers for RA, there have been hardly any reports regarding ACPAs in ankylosing spondylitis (AS). The possible role of antibodies to Mycobacterial 65 kDa heat shock protein (hsp65) has not been characterized in AS. As new laboratory biomarkers of AS are needed, we investigated the prevalence of anti-mutated citrullinated vimentin (MCV) and anti-hsp65 antibodies in AS.
  
  
  METHODS
  Altogether 43 AS and 44 healthy controls were included in the study. Anti-MCV and anti-hsp65 were determined in sera by commercial and in-house ELISA, respectively. Serum autoantibody levels were correlated with ESR, CRP, HLA-B27 status, smoking habits, pain intensity, BASDAI, BASFI and BASMI indices.
  
  
  RESULTS
  Patients with AS had significantly higher serum anti-MCV levels (17.3 U/mL, range: 8.3-31.5 U/mL) in comparison to healthy subjects (8.9 U/mL, range: 5.4-13.3 U/mL) (p<0.01). Sixteen of the 43 AS patients (37%) and none of the 44 healthy controls (0%) were anti-MCV positive using the cut-off value recommended by the manufacturer (>20 U/mL). The mean anti-hsp65 concentration in AS sera was 124.8 AU/mL (range: 27.2-1000 AU/mL), while controls exerted significantly lower anti-hsp65 levels (mean: 51.8 AU/mL; range: 22.5-88.5 AU/mL) (p<0.001). Correlation analysis revealed that both anti-MCV positivity (r=0.613; p=0.012) and absolute serum anti-MCV levels (r=0.553; p=0.021) correlated with anti-hsp65 levels. Anti-MCV positivity also correlated with ESR (r=0.437; p=0.03).
  
  
  CONCLUSIONS
  Anti-MCV and anti-hsp65 may be novel biomarkers in AS.
authors.affiliation: Department of rheumatology, institute of medicine, medical and health science center, university of Debrecen, 98, Nagyerdei street, 4012 Debrecen, Hungary.
authors.forename: Nóra
authors.initials: N
authors.lastname: Bodnár
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Szekanecz
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Prohászka
authors.forename: Adám
authors.initials: A
authors.lastname: Kemény-Beke
authors.forename: Zsuzsanna
authors.initials: Z
authors.lastname: Némethné-Gyurcsik
authors.forename: Katalin
authors.initials: K
authors.lastname: Gulyás
authors.forename: Gabriella
authors.initials: G
authors.lastname: Lakos
authors.forename: Sándor
authors.initials: S
authors.lastname: Sipka
authors.forename: Sándor
authors.initials: S
authors.lastname: Szántó
mesh_terms: D000328:Adult; D000368:Aged; D001323:Autoantibodies / Q000097:blood* / Q000235:genetics; D001426:Bacterial Proteins / Q000276:immunology*; D015415:Biomarkers / Q000097:blood; D018834:Chaperonin 60 / Q000276:immunology*; D002956:Citrulline / Q000235:genetics / Q000276:immunology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010456:Peptides, Cyclic / Q000276:immunology*; D013167:Spondylitis, Ankylosing / Q000097:blood / Q000175:diagnosis* / Q000276:immunology; D014746:Vimentin / Q000235:genetics / Q000276:immunology*
chemical_list: D001323:Autoantibodies; D001426:Bacterial Proteins; D015415:Biomarkers; D018834:Chaperonin 60; D010456:Peptides, Cyclic; D014746:Vimentin; C487763:cyclic citrullinated peptide; C074119:heat-shock protein 65, Mycobacterium; D002956:Citrulline