Objective: A dysregulated local immune defence with a constant influx of leucocytes provides a basis for continuous intestinal inflammation in ulcerative colitis and Crohn's disease. Since vascular adhesion protein 1 (VAP-1) is one of the adhesion molecules that mediates lymphocyte binding to endothelium, we investigated the levels of soluble VAP-1 (sVAP-1) in the sera of inflammatory bowel disease (IBD) patients compared with healthy controls.

Methods: sVAP-1 serum levels were measured in 161 IBD patients (90 ulcerative colitis, 71 Crohn's disease) and 93 controls using a commercially available enzyme-linked immunosorbent assay (ELISA). sVAP-1 levels were correlated with disease activity and localization. In 42 patients, sVAP-1 levels were measured in both the active and inactive phases of the disease.

Results: sVAP-1 serum levels were detected in all control and IBD subjects. Mean sVAP-1 levels were 365.5 +/- 153.5 ng/ml in ulcerative colitis patients, 336.4 +/- 172.8 ng/ml in Crohn's disease patients, and 344.7 +/- 150.4 ng/ml in healthy controls. The differences between the groups were not significant. No association between disease activity or disease localization and sVAP-1 was found.

Conclusions: sVAP-1 serum concentrations are not significantly different in IBD and healthy control subjects. sVAP-1 serum levels are of no value in the assessment of disease activity or severity of inflammation in patients with IBD.