CIRCULATING SKIN-HOMING T-CELLS IN ATOPIC-DERMATITIS - SELECTIVE UP-REGULATION OF HLA-DR, INTERLEUKIN-2R, AND CD30 AND DECREASE AFTER COMBINED UV-A AND UV-B PHOTOTHERAPY

Background: As the cutaneous lymphocyte-associated antigen appears to detect circulating T cells that migrate to the skin in atopic dermatit is but not T cells that migrate to mucosal sites in allergic asthma an d rhinitis, we investigated T-cell activation markers and CD30 on the cutaneous lymphocyte-associated antigen-positive circulating T-cell su bset in atopic dermatitis to see whether these markers are different f rom those in normal controls and related to disease activity. Design: Open study. Setting: University referral center. Patients: Twelve pati ents with atopic dermatitis and 12 healthy controls. Intervention: Com bined UV-A and UV-B treatment for 2 months. Main Outcomes Measures: Pe rcentage of circulating cutaneous lymphocyte-associated antigen-positi ve T cells that express HLA-DR, interleukin-2 receptor, CD69, CD71, an d CD30 (triple-color flow cytometric analysis). Clinical score, Dermat ology Life Quality Index, pruritus score, and consumption of topical c orticosteroids were determined. Results: Increased relative numbers of cutaneous lymphocyte-associated antigen-positive T cells expressing H LA-DR, interleukin-2 receptor, and CD30 were found in patients with at opic dermatitis before treatment. Treatment with UV-A and UV-B was ass ociated with clinical improvement and a decrease of levels of HLA-DR, interleukin-2 receptor, and CD30 in cutaneous lymphocyte-associated an tigen-positive T cells. HLA-DR on cutaneous lymphocyte-associated anti gen-positive T cells correlated significantly with the clinical score. Conclusion: Expression of HLA-DR and interleukin-2 receptor is a sens itive marker of disease activity in atopic dermatitis. Apart from givi ng information on disease activity in atopic dermatitis, the availabil ity of skin-seeking T cells in the blood offers the opportunity to obt ain further information on T cells that may have effector function in the skin.