CIRCULATING SOLUBLE ADHESION MOLECULES IN PATIENTS WITH CLASSICAL POLYARTERITIS-NODOSA

The objective was to evaluate whether changes in circulating soluble a dhesion molecule levels reflect disease activity in patients with syst emic polyarteritis nodosa (PAN). A sandwich ELISA was used to measure soluble (s) intercellular adhesion molecule 1 (sICAM-1), vascular cell adhesion molecule 1 (sVCAM-1), E-selectin, L-selectin and P-selectin in sera and plasma from 22 patients with active PAN, in sera from 13 o f these patients taken serially during follow-up, and in sera from 13 healthy controls. At the time of diagnosis, sICAM-1, sVCAM-1 and sE-se lectin levels (488.5 +/- 201.3, 1176.5 +/- 514.1 and 60.6 +/- 27 ng/ml , respectively) were significantly higher in patients than in controls (P < 0.0001, P = 0.001 and P = 0.003, respectively). In contrast. sL- selectin levels tended to be lower in patients than in controls. Withi n the first 7 days after starting treatment, there was a significant i ncrease in sICAM-1 concentrations, which fell thereafter, but did not completely reach normal levels When patients achieved clinical remissi on. sE-selectin also remained elevated during follow-up. Only sVCAM-1 decreased. tending to reach normal values in inactive disease. Increas ed levels of sICAM-1, sVCAM-1 and sE-selectin, and decreased levels of sl-selectin, in active PAN suggest immune and endothelial stimulation during disease activity. Abnormal levels of soluble adhesion molecule s in clinically inactive patients might reflect persistence of immune activation and/or endothelial cell exposure to a remaining inflammator y microenvironment.