Immunocytochemical localization of inducible nitric oxide synthase and transforming growth factor-beta (TGF-β) in leprosy lesions

Abstract

Inducible nitric oxide synthase (iNOS) and TGF-β were localized by immunocytochemistry in skin lesions from patients across the leprosy spectrum, and from patients undergoing reversal reaction. iNOS expression was highest at the tuberculoid pole of the spectrum, and increased during reversal reaction. TGF-β was observed throughout the leprosy spectrum, but was highest at the lepromatous pole. Levels of TGF-β decreased during reversal reaction. Reduced levels of TGF-β may contribute to unregulated inflammatory responses during reactional episodes.