TH2-LIKE CYTOKINE ACTIVITY IN DERMATITIS-HERPETIFORMIS

Dermatitis herpetiformis (DH) is a chronic subepidermal blistering dis ease, in which a perivascular cellular infiltrate, composed mainly of CD4+ T lymphocytes together with a varying number of neutrophils and e osinophils, is thought to be important in the pathogenesis of blister formation, The aim of this study was to investigate the potential role of cytokines such as the interleukins IL-4 and IL-5 and to quantify t he distribution of T cells as well as their state of activation using alkaline phosphatase-antialkaline phosphatase and reverse transcriptas e-polymerase chain reaction (RT-PCR) procedures in seven patients with typical clinical and histological features of DH. A strong extracellu lar staining with anti-IL-4 monoclonal antibody was detected in the up per dermis with a prevalent perivascular pattern in perilesional areas , whereas in the dermal-epidermal separation sites there was an intens e, scattered distribution, IL-5 was intensely expressed, mainly at the intracellular level, by eosinophils and lymphocytes. Concerning RT-PC R, fire DH patients showed a strong positive signal for both IL-4 and IL-5 cytokines while two patients shelved a faint signal for both IL-4 and IL-5: these last two cases were histologically poor in inflammato ry cells, In vie nr of these results, it can be hypothesized that the recruitment of eosinophils and neutrophils in DH may be induced not on ly by granulocyte macrophage colony-stimulating factor and IL-8 as pre viously demonstrated, but also by Th2 cytokines as well.