Normal numbers of T6 positive epidermal Langerhans cells across the leprosy spectrum

Abstract

Langerhans cells (LC) in the skin lesions of 25 untreated leprosy patients were defined by indirect immunofluorescence using monoclonal antibodies against phenotypic markers T6 and Ia like antigens. Normal numbers of epidermal LC were seen in leprosy lesions. No differences were observed in the intensity of fluorescence or in the numbers of T6+Ia+LC across the leprosy spectrum. However, the dermal granulomas of tuberculoid leprosy (TT/BT) showed a high proportion of T6+cells in the mononuclear infiltrate surrounding the epithelioid cells. Smaller numbers of these cells were seen in borderline leprosy (BB,BL) with a virtual absence in polar lepromatous leprosy (LL). Ia like antigens were associated with the macrophages in BL and LL granulomas and with the lymphocytes in tuberculoid lesions. B cells were conspicuously absent in all leprosy lesions.