Immunohistochemical study of Langerhans cells in cutaneous lesions of the Jorge Lobo's disease.

ABSTRACT

Jorge Lobo's disease is a chronic infection caused by the fungus Lacazia loboi endemic in South America. The infection is characterized by the appearance of parakeloidal, ulcerated or verrucous nodular or plaque-like cutaneous lesions. The histopathological aspect is characterized by poorly organized granulomas with histiocytes and multinucleated giant cells. Little is known about local immune response in lobomycosis skin lesions. Thirty-three skin biopsies from patients with Jorge Lobo's disease were selected from Ambulatory of Dermatology, UFPA. The control group was constituted by ten biopsies from normal skin. Langerhans cells were identified by immunohistochemistry using anti-CD1a antibody (Serotec). The number of positive cells was statistically analyzed. Langerhans cells were visualized along the epidermis in biopsies from Jorge Lobo's disease and the morphology and the number of Langerhans cells did not differ from normal skin (p>0.05). In Jorge Lobo's disease, this cell population probably presents some escape mechanism of the local immune system to evade the antigen presentation by those cells.