Immunohistochemical characterization of the cellular infiltrate in localized scleroderma

Localized scleroderma is a connective tissue disorder with hardening of the skin and fibrosis of the affected tissue as the most prominent features. The etiology of localized scleroderma is still unknown, but immunologic factors may play an important role in the pathogenesis. This study was performed to determine the immunohistochemical features of the cellular infiltrate in localized scleroderma.Skin samples were obtained from six patients by 6-mm punch biopsy. The samples were stained with monoclonal antibodies against CD1a, CD3, CD4, CD8, CD20, CD25, CD30, and CD57. The number of cells stained with each monoclonal antibody was calculated.There were more CD1a+, CD3+, CD4+, CD8+, CD20+, CD25+, and CD57+ cells in the dermal infiltrate in localized scleroderma relative to those in normal controls. The numbers of CD1a+, CD3+, CD4+, CD8+, and CD57+ cells in localized scleroderma were significantly greater than those in normal skin (P < 0.05). The number of CD30+ cells in localized scleroderma was almost the same as that in normal skin.This study reveals that T lymphocytes, Langerhans cells, and natural killer cells may play important roles in the pathogenesis of localized scleroderma.