title: Cytokine expression in the duodenal mucosa of patients with visceral leishmaniasis.
abstract: BACKGROUND
  Visceral leishmaniasis (VL) is a neglected tropical disease with a complex immune response in different organs. This pattern of organ-specific immune response has never been evaluated in the gastrointestinal tract. The aim of this study was to determine the in situ immune response in duodenal biopsies on patients with VL.
  
  
  METHODS
  A case-control study was conducted on 13 patients with VL in comparison with nine controls. The immune response was evaluated using immunohistochemistry, for CD4, CD8, CD68, IL-4, IFN-gamma, TNF-alpha and IL-10. Histological findings from the villi, crypts and inflammatory process were analyzed.
  
  
  RESULTS
  All the cases of VL presented Leishmania antigens. No antigen was detected in the control group. The villus size was greater in the VL patients (p < 0.05). CD68 (macrophages) and CD4 levels were higher in the VL patients (p < 0.05). No differences in the expression of CD8, TNF-alpha, IL-10 or IL-4 were demonstrated. The number of cells expressing IFN-gamma was lower in the VL patients (p < 0.05).
  
  
  CONCLUSIONS
  Low levels of cytokines were found in the gastrointestinal tract of patients with VL. This pattern was not found in other organs affected by the disease. Immunotolerance of this tissue against Leishmania could explain these findings, as occurs with intestinal bacteria.
authors.affiliation: Department of Infectious Diseases, Federal University of Rio Grande do Norte, Natal, RN, Brazil. luz@ufrnet.br
authors.forename: Kleber Giovanni
authors.initials: KG
authors.lastname: Luz
authors.forename: Felipe Francisco
authors.initials: FF
authors.lastname: Tuon
authors.forename: Maria Irma Seixas
authors.initials: MI
authors.lastname: Duarte
authors.forename: Guilherme Mariz
authors.initials: GM
authors.lastname: Maia
authors.forename: Paulo
authors.initials: P
authors.lastname: Matos
authors.forename: Ana Maria de Oliveira
authors.initials: AM
authors.lastname: Ramos
authors.forename: Antônio Carlos
authors.initials: AC
authors.lastname: Nicodemo
mesh_terms: D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D016207:Cytokines / Q000032:analysis* / Q000276:immunology; D004386:Duodenum / Q000276:immunology* / Q000469:parasitology; D006801:Humans; D007150:Immunohistochemistry; D007223:Infant; D007413:Intestinal Mucosa / Q000276:immunology* / Q000469:parasitology; D007898:Leishmaniasis, Visceral / Q000276:immunology* / Q000473:pathology; D008264:Macrophages / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D016207:Cytokines