Autoantibody against peroxiredoxin I, an antioxidant enzyme, in patients with systemic sclerosis: possible association with oxidative stress.

Abstract

OBJECTIVES:

To determine the prevalence and clinical correlation of autoantibody to peroxiredoxin (Prx) I, an antioxidant enzyme, in patients with systemic sclerosis (SSc).

METHODS:

Serum samples from SSc patients (n = 70) and healthy controls (n = 23) were examined by ELISA using human recombinant Prx I. The presence of anti-Prx I antibody was further evaluated by immunoblotting analysis. To determine the functional relevance of anti-Prx I antibody in vivo, we assessed whether anti-Prx I antibody was able to inhibit Prx I enzymatic activity using yeast thioredoxin reductase system.

RESULTS:

IgG anti-Prx I antibody levels in SSc patients were significantly higher than healthy controls and this autoantibody was detected in 33% of SSc patients. The presence of IgG anti-Prx I antibody was associated with longer disease duration, more frequent presence of pulmonary fibrosis, heart involvement, and anti-topoisomerase I antibody and increased levels of serum immunoglobulin and erythrocyte sedimentation rates. IgG anti-Prx I antibody levels also correlated positively with renal vascular damage and negatively with pulmonary function tests. Furthermore, anti-Prx I antibody levels correlated positively with serum levels of 8-isoprostane, a marker of oxidative stress. Immunoblotting analysis confirmed the presence of anti-Prx I antibody. Remarkably, Prx I enzymatic activity was inhibited by IgG isolated from SSc sera containing IgG anti-Prx I antibody.

CONCLUSIONS:

These results suggest that elevated IgG anti-Prx I autoantibody is associated with the disease severity of SSc and that anti-PrxI antibody may enhance the oxidative stress by inhibiting Prx I enzymatic activity.

• Authors: Y Iwata, F Ogawa, K Komura, E Muroi, T Hara, K Shimizu, M Hasegawa, M Fujimoto, Y Tomita, S Sato
• Journal: Rheumatology (Oxford, England) (Rheumatology (Oxford)) Vol. 46 Issue 5 Pg. 790-5 (May 2007) ISSN: 1462-0324 [Print] England
• PMID: 17309887 (Publication Type: Journal Article)

Chemical References

• Antioxidants
• Autoantibodies
• Enzyme Inhibitors
• Immunoglobulin G
• 8-epi-prostaglandin F2alpha
• Dinoprost
• Peroxidases
• Peroxiredoxins

Topics

• Adult
• Aged
• Antioxidants (physiology)
• Autoantibodies (blood)
• Dinoprost (analogs & derivatives, blood)
• Enzyme Inhibitors (pharmacology)
• Enzyme-Linked Immunosorbent Assay (methods)
• Female
• Humans
• Immunoglobulin G (blood, pharmacology)
• Male
• Middle Aged
• Oxidative Stress (immunology)
• Peroxidases (antagonists & inhibitors, immunology)
• Peroxiredoxins
• Pulsatile Flow
• Scleroderma, Systemic (immunology)
• Severity of Illness Index
• Vital Capacity