Etiopathogenisis 3. Abnormal immune function cellular immunity function reduce partly Oearly skin lesions are infiltrated predominantly by lymphocytes Autoantibody deposit in the horny layer OThI/Th2 disequilibrium theory(ThI dominant skin disease)Etiopathogenisis 3.Abnormal immune function : ⚫cellular immunity function reduce partly ⚫early skin lesions are infiltrated predominantly by lymphocytes ⚫autoantibody deposit in the horny layer ⚫Th1/Th2 disequilibrium theory(Th1 dominant skin disease)