SERUM-SOLUBLE CD23 LEVELS AND CD23 EXPRESSION ON PERIPHERAL-BLOOD MONONUCLEAR-CELLS IN JUVENILE CHRONIC ARTHRITIS

Objective To assess the CD23 status in patients with juvenile chronic arthritis (JCA), as defined by set-rim soluble CD23 (sCD23) and the ex pression of CD23 on peripheral blood mononuclear cells. Methods Serum sCD23 levels were measured by ELISA in 22 patients with systemic JCA ( s-JCA), in 40 patients with antinuclear antibody positive pauciarticul ar JCA (ANA + p-JCA), and in 38 healthy controls. CD23 expression on T cells, B cells, and monocytes was determined by flow cytometry analys is of double fluorescence staining. Results Serum sCD23 levels were in creased in both ANA + p-JCA and s-JCA; 120 relation with disease activ ity or severity was found. In patients With ANA + p-JCA, serum sCD23 l evels were correlated with an increased percentage of B cells expressi ng CD23, while in patients with s-JCA the serum sCD23 levels were corr elated with an increased percentage of monocytes expressing CD23. Conc lusion Serum sCD23 levels are elevated both in systemic and ANA + pauc iarticular JCA : different cell subset CD23 expression in s-JCA and AN A + p-JCA (i.e. monocyte or B cell, respectively) suggests that in pau ciarticular JCA CD23 may be implicated in B cell activation and autoan tibody production, while in systemic JCA may be involved in monocyte a ctivation and in the release of inflammatory mediators.