Plasma soluble CD30 level correlates negatively with age in children.

BACKGROUND AND PURPOSE Atopic diseases are thought to be associated with cytokine-mediated immune dysregulation, for example, a T helper cell type 1/2 (Th1/Th2) imbalance. CD30 is proposed to be one of the surrogate markers for Th2 immunity. In this study, we investigated whether CD30 is a good marker for atopy and Th2 predominance in a pediatric population. METHODS This study included 61 children with atopy and 27 normal controls. The expression of CD30 on the surface of T and B lymphocytes and soluble CD30 (sCD30) in plasma was determined. RESULTS There was no difference in the surface expression of CD30 on B or T lymphocytes. Similarly, sCD30 levels in plasma were not different between the 2 groups. Nevertheless, we found a strong negative correlation between sCD30 and age in the control group (r = -0.72, p<0.001; sCD30 = 76.1 - 5.18 x age) as well as in the atopy group (r = -0.45, p<0.01; sCD30 = 61.1 - 3.56 x age). CONCLUSIONS An inverse relationship was found between age and sCD30 level in children. However, our findings suggest that CD30 is not a good marker for atopic disease and that further studies on sCD30 levels must take age into consideration.