Increased circulating soluble vascular adhesion protein-1 levels in systemic sclerosis: association with lower frequency and severity of interstitial lung disease.

Aim: To determine circulating soluble vascular adhesion protein-1 (sVAP-1) levels and their clinical associations in patients with systemic sclerosis (SSc).

Method: Serum VAP-1 levels were examined by enzyme-linked immunosorbent assay in 71 SSc patients, 13 systemic lupus erythematosus patients and 50 healthy individuals.

Results: Serum sVAP-1 levels were significantly elevated in SSc patients (617.2 ± 338.7 ng/mL) compared with healthy individuals (320.2 ± 144.2 ng/mL; P < 0.001) and patients with systemic lupus erythematosus (329.0 ± 176.1 ng/mL; P < 0.001). Among SSc patients, there were no differences in serum sVAP-1 levels between those with limited cutaneous SSc and those with diffuse cutaneous SSc. SSc patients with raised sVAP-1 levels had interstitial lung disease and decreased percent vital capacity less often than those with normal sVAP-1 levels. sVAP-1 levels were positively correlated with percent vital capacity in patients with SSc.

Conclusion: Serum sVAP-1 levels were increased in patients with SSc, and associated with a lower frequency and severity of interstitial lung disease in SSc, suggesting that sVAP-1 plays a role in the pathogenesis of interstitial lung disease in SSc.