Detection of cytokines and nitric oxide synthase in skin lesions of Jorge Lobo's disease patients

Studies investigating the immunopathological aspects of Jorge Lobo ' s disease have shown that the infl ammatory infi ltrate consists mainly of histiocytes and multinucleated giant cells involving numerous yeast-like cells of Lacazia loboi , with the T lymphocytes more common than B lymphocytes and plasma cells. The quantifi cation of cytokines in peripheral blood mononuclear cells culture supernatant has revealed alterations in the cytokines profi le, characterized by predominance of a Th2 profi le. In view of these fi ndings and of the role of cytokines in cell interactions, the objective of the present study was to investigate the presence of the cytokines IL-10, TGF- s 1 and TNF- α , as well as iNOS enzyme in granulomas induced by L. loboi . Histological sections obtained from skin lesions of 16 patients were analyzed by immunohistochemistry for the pres- ence of these cytokines and iNOS. The results showed that TGF- s 1 was the cytokine most frequently expressed by cells present in the infl ammatory infi ltrate, followed by IL-10. There was a minimum to discrete positivity of cells expressing TNF- α and iNOS. The results suggest that the presence of immunosuppressive cytokines in skin lesions of patients with the mycosis might be responsible for the lack of containment of the patho- gen as demonstrated by the presence of numerous fungi in the granuloma.