The presence of surface CD30 on T cells in atopic dermatitis.

Atopic dermatitis (AD) has cellular immunohistochemical features similar to those of allergic contact dermatitis (ACD) and there is plenty of evidence for T-cell activation in this disease. The involvement of CD30+ T cells in acute stages of atopic dermatitis might establish CD30 as a helpful marker in differentiating those two diseases. Tissue sections from the skin of 12 patients with active atopic dermatitis and 13 with allergic contact (nickel-induced) dermatitis were immunohistochemically analyzed for cell-surface antigens, including CD30, CD3, CD4, and CD45RO. The severity of the disease was graded by the SCORAD clinical scoring system. The analysis of CD30+, CD45RO+, CD3+, and CD4+ cells in the dermis and epidermis showed a much wider range of values and statistically higher median (p<0.01) in the inflammatory infiltrate of acute atopic dermatitis compared with that of allergic contact dermatitis. Our results showed an association of CD30 expression with atopic dermatitis, but not allergic contact dermatitis. CD30 expression in AD might be helpful in histologic differentiation of these disorders and further characterization of atopy patch testing. The results suggested a specific regulatory function of CD30+ T cells in acute AD. Abundant CD45R0+ cells were detected in both AD and ACD lesions.