Assesment of soluble ICAM-1 and soluble E-selectin in juvenile idiopathic arthiritis: clinical and laboratory correlation

ABSTRACT

Juvenile idiopathic arthritis [JIA] is a systemic inflammatory disease with dysregulation of normal immune responses that lead to chronic tissue inflammation and damage. Synovial neoangiogenesis, one of the pathologic hallmarks of JIA, was recently found to be caused mainly by vascular endothelial cell growth factor and was associated with increased infiltration of inflammatory cells. The activation, migration and penetration of leukocytes into local inflammatory tissues are dependent on attachment to adhesion molecules on endothelial cells. For that reason, adhesion molecules are belived to play part in initiation and propagation of autoimmune diseases. So the aim of this work is to measure serum and synovial fluid [SF] concentrations of soluble adhesion molecule-1 [ICAM-1] and E-selectin in juvenile idiopathic arthritis patients and to correlate them with clinical and laboratory variables. A Sandwish ELISA technique was used to estimate the serum and synovial levels of soluble intercellular adhesion molecule-1 [ICAM-1] and E-selectin in 38 patients with JIA, 12 systemic [JIA-sys], 13 polyarticular [JIA-poly] and 13 oligoarticular [JIA-oligo.], who had active disease or were in clinical remission. Fifteen healthy subjects matched in sex and age with the patients group were studied as control group. The total leukocytic [blood and synovial] and platelet counts, erythrocyte sedimentation rate [ESR] and Creactive protein [CRP] were recorded. A significantly higher level of sICAM-1 and E-selectin [p < 0.001 and < 0.05, respectivley] were found in [JIA-sys] and [JIA-poly] than in [JIA-oligo] or in control group. The level of both molecules in the three JIA subtypes, in the active stages and clinical remission, were still higher than in control group. A significant negative correlation with age was observed for the group as a whole [p < 0.001 for both, sICAM-1 r = - 0.581 and sE- selectin r = - 0.497] while no correlation was found with disease duration or ESR. sE-selectin was correlated with total blood leukocytic and platelet counts [p < 0.05 for both, r = 0.37 and 0.34, respectivley] and both molecules with CRP [p < 0.05, ICAM-1 r = 0.33 and E- selectin r = 0.35] and with each other [p < 0.01, r = 0.600]. No correlation was found between serum and synovial adhesion molecules [p > 0.05] or between SF adhesion molecules concentration and total SF leukocytic count [p > 0.05]. Increased level of soluble adhesion molecules in both [JIA-sys] and [JIA-poly] may be due to endothelial cell activation which is the key to the pathogenesis of JIA especially in systemic subtype and its persistence in spite of clinical remission could be used as a marker of aggressive disease