Immunohistochemical study of skin biopsies in dermatomyositis

In the present study,6 monoclonal anitbodies were used to determine the cellular composition of skin infiltrates eta affected and clinically uninvolved skin of patients with dermatomyositis The majority of cells detected in the lesional infiltrate were T-lymphocytes, especially T-helper and,macrophages. B-cells were almost absent lesional epidermal Langerhans cells' density was not different from normal skin, but cells were less dendritic and showed irregular distribution in lesional skin. These findings are different from dermatomyositis muscle infiltrate but are similar to those detected in skin affected by cutaneous lupus erythematosus In autoimmune diseases,cellular infiltrates may be more organ-specific than disease-specific