Jorge Lobo's disease: immunohistochemical characterization of dendritic cells in cutaneous lesions.

Abstract

Jorge Lobo's disease (JLD) is a cutaneous chronic mycosis caused by Lacazia loboi. We studied Factor XIIIa + dermal dendrocytes (FXIIIa + DD), Langerhans cells (LC) through the expression of langerin and the expression of S100 protein. A total of 41 biopsies and 10 normal skins (control) were developed with a polymer-based immunohistochemical method. Lesions presented infiltrate comprising macrophages, some asteroid corpuscles, lymphocytes, multinucleated giant cells and a large number of fungi. LCs presented short dendrites and were scarcely distributed. Dermal langerin + cells were detected in nine JLD lesions. FXIIIa + DD were hypertrophic, visualized in the inflammatory infiltrate of JLD lesions. Cells S100+ were present in JLD and control group with a similar number of cells. A total of 14 specimens did not express FXIIIa, and this considerable number probably contributed to the statistical similarity with the control group. The results indicate that LCs are present in the immune response against Lacazia loboi. Some dermal langerin + cells could be another subset of dendritic cells. Our data indicate changes of LCs in JLD cutaneous lesions and present, for the first time, results that show langerin + cells in the dermis and corroborate previous observations on the participation of FXIIIa + DD in the in situ immune response in JLD.