Langerhans Cells, Natural Killer Cells, T and B Lymphocytes in Early Morphea: An Immunohistochemical Study

Background. Scleroderma (morphea) is a connective tissue disorder, characterized by thickening and induration of the skin and subcutaneous tissue due to excessive collagen deposition. The pathogenesis of morphea is still not completely delineated, however, immunologic factors may play an important role. Objective. To determine the immunophenotypic expression of the cellular infiltrate in early morphea and compare between this cellular infiltrate in both generalized and localized morphea. Patients and methods. Skin specimens were taken from 9 patients with early morphea [6 localized (5 plaque and one linear) and 3 generalized] by 6 mm punch biopsy and from 9 controls. The samples were stained with monoclonal antibodies against CD1a+, CD3+, CD20+ and CD57+. The number of cells stained with each monoclonal antibody was counted. Comparison of the cellular infiltrate between localized and generalized morphea was done. Results. There were more CD1a+ (7.45 ± 2.15), CD3+ (34.80 ± 24.6), CD20+ (3.94 ± 3.75) and CD57+ (9.72 ± 1.72) cells in the dermal infiltrate in early morphea relative to those in normal controls CD1a+ (2.44 ± 0.88), CD3+ (6.84 ± 5.12), CD20+ (1.44 ± 0.19), CD57+ (1.55 ± 0.77). The numbers of CD1a+, CD3+, CD57+ cells in early morphea were significantly higher than those in normal skin (p 0.05). There was no statistically significant difference in the numbers of CD1a+, CD3+, CD20+ and CD57+ between localized and generalized morphea (p 0.05). Conclusion. Langherhans cells, T-lymphocytes and natural killer cells may play important role in the pathogenesis of early morphea. Types and numbers of the cellular infiltrate are not predictive for the development of localized or generalized morphea.