title: Human mucosal leishmaniasis: neutrophils infiltrate areas of tissue damage that express high levels of Th17-related cytokines.
abstract: Mucosal leishmaniasis (ML) is characterised by severe tissue destruction. Herein, we evaluated the involvement of the IL-17-type response in the inflammatory infiltrate of biopsy specimens from 17 ML patients. IL-17 and IL-17-inducing cytokines (IL-1β, IL-23, IL-6 and TGF-β) were detected by immunohistochemistry in ML patients. IL-17(+) cells exhibited CD4(+), CD8(+) or CD14(+) phenotypes, and numerous IL-17(+) cells co-expressed the CC chemokine receptor 6 (CCR6). Neutrophils, a hallmark of Th17-mediated inflammation, were regularly detected in necrotic and perinecrotic areas and stained positive for neutrophil elastase, myeloperoxidase and MMP-9. Taken together, these observations demonstrate the existence of Th17 cells in ML lesions associated with neutrophils in areas of tissue injury and suggest that IL-17 is involved in ML pathogenesis.
authors.affiliation: Centro de Pesquisas Gonçalo Moniz, Fundação Oswaldo Cruz, Salvador, Brazil.
authors.forename: Viviane S
authors.initials: VS
authors.lastname: Boaventura
authors.forename: Claire S
authors.initials: CS
authors.lastname: Santos
authors.forename: Cristina R
authors.initials: CR
authors.lastname: Cardoso
authors.forename: José
authors.initials: J
authors.lastname: de Andrade
authors.forename: Washington L C
authors.initials: WL
authors.lastname: Dos Santos
authors.forename: Jorge
authors.initials: J
authors.lastname: Clarêncio
authors.forename: João S
authors.initials: JS
authors.lastname: Silva
authors.forename: Valeria M
authors.initials: VM
authors.lastname: Borges
authors.forename: Manoel
authors.initials: M
authors.lastname: Barral-Netto
authors.forename: Claudia I
authors.initials: CI
authors.lastname: Brodskyn
authors.forename: Aldina
authors.initials: A
authors.lastname: Barral
mesh_terms: D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D020381:Interleukin-17 / Q000096:biosynthesis / Q000276:immunology*; D007891:Leishmania / Q000276:immunology*; D007897:Leishmaniasis, Mucocutaneous / Q000276:immunology* / Q000469:parasitology; D008297:Male; D020780:Matrix Metalloproteinase 9 / Q000097:blood / Q000276:immunology; D018613:Microscopy, Confocal; D008875:Middle Aged; D009504:Neutrophils / Q000201:enzymology / Q000276:immunology*; D057132:Nuclear Receptor Subfamily 1, Group F, Member 3 / Q000276:immunology; D009195:Peroxidase / Q000097:blood / Q000276:immunology; D054399:Receptors, CCR6 / Q000276:immunology*; D018709:Statistics, Nonparametric
chemical_list: C106311:CCR6 protein, human; D020381:Interleukin-17; D057132:Nuclear Receptor Subfamily 1, Group F, Member 3; D054399:Receptors, CCR6; D009195:Peroxidase; D020780:Matrix Metalloproteinase 9; C501830:Mmp9 protein, mouse