T lymphocytes and macrophages in the intestinal tissues of dogs infected with Leishmania infantum

Author(s)

Diogo Tiago da Silva ; Maria Luana Alves ^[2] ; Júlio Cesar Pereira Spada ; Aline Cristine da Silva ^[4] ; Rita de Cássia Viveiros da Silveira ^[5] ; Trícia Maria Ferreira de Sousa Oliveira ^[6] ; Wilma Aparecida Starke-Buzetti ^[7]

• Document type: Journal article
• Source: Revista Brasileira de Parasitologia Veterinária; v. 26, n. 2, p. 159-170, 2017-06-00.

Abstract

Abstract This study was about a semi-quantitative analysis of T lymphocytes (CD4+ and CD8+, FoxP3+ regulatory T cells), and macrophages in the gut wall of dogs naturally infected with Leishmania infantum. Thirteen dogs were divided into three groups: group 1 (G1, n=5), dogs with canine visceral leishmaniasis (CVL) and infected with L. infantum amastigotes in the intestine; group 2 (G2, n=5), dogs with CVL but without intestinal amastigotes; and group 3 (G3, n=3), uninfected dogs (control group). There was no significant difference (p ≥ 0.05) on CD4+ and Treg cell numbers among the groups, whereas the levels of CD8+ T cells and macrophages were significantly higher in dogs from G1 group than in G2 and G3 (p ≤ 0.05), especially in intestinal segments with high parasite burden. Parasite burden correlated positively with levels of CD8+ T cells and macrophages (p ≤ 0.05), but was inversely correlated to levels of CD4+ T lymphocytes and FoxP3+ Treg cells. In conclusion, in the intestine of dogs with CVL, the increase of CD8+ T cells and macrophages population associated with high parasite burdens, but no changes of CD4+ T cells and FoxP3+ Treg cells suggest a possible immunoregulation by the parasite not dependent on Treg cells. (AU)

• FAPESP's process: 13/13875-5 - Correlation of the granulocytic and monocytic cell profiles in the intestine of dogs naturally infected with Leishmania infantum
• Grantee: Diogo Tiago da Silva
• Support Opportunities: Scholarships in Brazil - Master