UNBALANCED PRODUCTION OF INTERLEUKIN-5 AND INTERLEUKIN-2 IN CHILDREN WITH ATOPIC-DERMATITIS

Background: Cytokines, such as interleukin (IL)-5, produced by T helpe r type 2 (Th2) cells appear to play an important role in the inflammat ory processes associated with atopic dermatitis, The roles of cytokine s produced by Th1 cells remain controversial. Objective: We examined I L-5 and IL-2 mRNA abundance in and protein production by peripheral bl ood mononuclear cells (PBMCs) from patients with atopic dermatitis and compared those from controls. Methods: Peripheral blood mononuclear c ells were isolated from six children with atopic dermatitis and six co ntrol children, and stimulated with both phytohemaggulutinin (PHA) and phorbol 12-myristate 13-acetate (PMA). The abundance of IL-5 and IL-2 mRNA in PBMCs was measured by reverse transcription-polymerase chain reaction analysis. The production of IL-5 and IL-2 by PBMCs was also d etermined by enzyme-linked immunosorbent assay. Results: After incubat ion with PHA and PMA, PBMCs from atopic children showed significantly higher IL-5 mRNA abundance (P < .05) and IL-5 production (P < .01), as well as a lower amount of IL-2 mRNA (P = .056) and IL-2 production (P < .05) than those from healthy controls. The time course of changes i n IL-5 mRNA abundance induced by PHA and PMA in PBMCs from atopic chil dren differed markedly from that observed with healthy controls, where as the time course of changes in IL-2 mRNA abundance were similar betw een the two groups. Conclusions: The increased IL-5 and decreased IL-2 production observed with PBMCs from children with atopic dermatitis m ay underlie the activation of eosinophils and high serum immunoglobuli n E concentrations also apparent in such individuals, An imbalance in the number and activity of Th1 and Th2 cells is likely to be responsib le for the abnormal pattern of cytokine production in atopic dermatiti s.