Serum antibodies against intact human collagen IX are elevated at onset of rheumatoid arthritis but are not related to development of erosions.

Publication/Presentation Date

5-1-2008

Abstract

OBJECTIVE: To measure the presence of autoantibodies binding to intact human recombinant collagen IX and assess their usefulness as a diagnostic marker and an indicator of disease activity in rheumatoid arthritis (RA).

METHODS: Recombinant human full-length collagen IX (rCIX) was produced in a baculovirus expression system and purified for use in ELISA developed to detect antibodies to native and denatured collagen IX. Fifty-three patients with recent-onset rheumatoid factor-seropositive RA were analyzed for the presence of rCIX antibodies of the IgG type at the time of initial diagnosis and after 3, 6, 12, and 24 months of followup. The RA sera were accompanied by 30 controls. Associations were determined between patients' antibody titers, development of erosions in the hands and feet, and various clinical and laboratory markers.

RESULTS: Serum antibody levels among patients with RA at time of diagnosis were 1.78 times higher against native rCIX (p < 0.001) and 1.71 times higher against denatured rCIX (p < 0.001) than in the controls, and they remained high during the followup. No correlation was seen between antibody levels and clinical and laboratory findings.

CONCLUSION: Our data show that patients with recent-onset RA have significantly elevated levels of autoantibodies to human rCIX. These autoantibodies were observed already at the early stages of the disease, which may reflect their diagnostic potential in RA.

Volume

35

Issue

5

First Page

745

Last Page

751

ISSN

0315-162X

Disciplines

Medicine and Health Sciences

PubMedID

18381798

Department(s)

Department of Pathology and Laboratory Medicine

Document Type

Article

Link to Full Text

Share

COinS