Expression of inducible nitric oxide synthase in macrophages inversely correlates with parasitism of lymphoid tissues in dogs with visceral leishmaniasis

Autor(es)

Sanches, Francoise P. ^[1] ; Tomokane, Thaise Y. ^[1] ; Da Matta, Vania L. R. ^[1] ; Marcondes, Mary ^[2] ; Corbett, Carlos E. P. ^[1] ; Laurenti, Marcia D. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Fac Med, Dept Patol, Lab Patol Molestias Infecciosas, BR-01246903 Sao Paulo - Brazil

^[2] Univ Estadual Paulista, Fac Med Vet, Dept Clin Cirurgia & Reprod Anim, Aracatuba, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: ACTA VETERINARIA SCANDINAVICA; v. 56, SEP 7 2014.
• Citações Web of Science: 7

Resumo

Background: There are only a few studies reporting the role of nitric oxide metabolites for controlling macrophage intracellular parasitism, and these are controversial. Therefore, the present study aimed to evaluate the expression of inducible nitric oxide synthase (iNOS) in the lymph nodes and spleen of dogs affected by visceral leishmaniasis through immunohistochemistry and to determine its correlation with tissue parasite burden and serum interferon (IFN)-gamma levels. Twenty-eight dogs were selected and assigned to one of two groups, symptomatic (n = 18) and asymptomatic (n = 10), according to clinical status and laboratory evaluation. A negative control group (n = 6) from a non-endemic region for visceral leishmaniasis was included as well. Results: Parasite density (amastigotes/mm(2)) was similar between clinical groups in the lymph nodes (P = 0.2401) and spleen (P = 0.8869). The density of iNOS(+) cells was higher in infected dogs compared to controls (P < 0.05), without a significant difference in lymph node (P = 0.3257) and spleen (P = 0.5940) densities between symptomatic and asymptomatic dogs. A positive correlation was found between the number of iNOS(+) cells in lymph nodes and interferon-gamma levels (r = 0.3776; P = 0.0303), and there was a negative correlation between parasites and iNOS+ cell densities both in lymph nodes (r = -0.5341; P = 0.0034) and spleen (r = -0.4669; P = 0.0329). Conclusion: The negative correlation observed between tissue parasitism and the expression of iNOS may be a reflection of NO acting on the control of parasites. (AU)

• Processo FAPESP: 04/07965-2 - Avaliacao da imunidade humoral e celular em caes naturalmente infectados com leishmania (l.) chagasi e sua correlacao com a transmissibilidade para o vetor.
• Beneficiário: Marcia Dalastra Laurenti
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 12/50285-9 - Avaliação clinica,imunologica e suas correlações com marcadores genéticos na leishmaniose visceral canina
• Beneficiário: Marcia Dalastra Laurenti
• Modalidade de apoio: Auxílio à Pesquisa - Regular