ABSTRACT
BACKGROUND: Porphyria cutanea tarda (PCT) is a metabolic disease characterized by vesicles and blisters in sun-exposed areas and scleroderma-like lesions in sun-exposed and non-sun-exposed areas. Mast cells participate in the pathogenesis of bullous diseases and diseases that show sclerosis, including PCT. Moreover, transforming growth factor-beta (TGF-beta) is the main cytokine in the development of tissue sclerosis. The correlation of mast cells and TGF-beta with the lesions of PCT has not been examined, however. The possible role of mast cells and TGF-beta (and the relationship between them) in the development of PCT lesions is discussed. METHODS: To quantify mast cells and cells expressing TGF-beta in skin samples from patients with PCT and controls, immunohistochemical studies were performed in tissue sections allied to morphometric analyses. RESULTS: The numbers of mast cells and cells expressing TGF-beta per square millimeter were increased in the PCT group relative to controls, and there was a direct and significant correlation between the mast cell number and cells expressing TGF-beta in PCT. CONCLUSIONS: The results suggest that the increased number of mast cells and of cells expressing TGF-beta, as well as their direct correlation, may contribute to the pathogenesis of the skin lesions in PCT.
