Silva Diogo Tiago da, Alves Maria Luana, Spada Júlio Cesar Pereira, Silva Aline Cristine da, Silveira Rita de Cássia Viveiros da, Oliveira Trícia Maria Ferreira de Sousa, Starke-Buzetti Wilma Aparecida
Departamento de Biologia e Zootecnia, Faculdade de Engenharia de Ilha Solteira - FEIS, Universidade Estadual Paulista - UNESP, Ilha Solteira, SP, Brasil.
Programa de Pós-graduação em Epidemiologia Experimental Aplicada às Zoonoses, Faculdade de Medicina Veterinária e Zootecnia - FMVZ, Universidade de São Paulo - USP, São Paulo, SP, Brasil.
Rev Bras Parasitol Vet. 2017 Apr-Jun;26(2):159-170. doi: 10.1590/S1984-29612017039.
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.
本研究旨在对自然感染婴儿利什曼原虫的犬肠道壁中的T淋巴细胞（CD4+和CD8+、FoxP3+调节性T细胞）和巨噬细胞进行半定量分析。13只犬被分为三组：第1组（G1，n = 5），患有犬内脏利什曼病（CVL）且肠道感染婴儿利什曼原虫无鞭毛体的犬；第2组（G2，n = 5），患有CVL但无肠道无鞭毛体的犬；第3组（G3，n = 3），未感染犬（对照组）。各组间CD4+和调节性T细胞数量无显著差异（p≥0.05），而G1组犬的CD8+ T细胞和巨噬细胞水平显著高于G2组和G3组（p≤0.05），尤其是在寄生虫负荷高的肠道段。寄生虫负荷与CD8+ T细胞和巨噬细胞水平呈正相关（p≤0.05），但与CD4+ T淋巴细胞和FoxP3+调节性T细胞水平呈负相关。总之，在患有CVL的犬的肠道中，CD8+ T细胞和巨噬细胞数量的增加与高寄生虫负荷相关，但CD4+ T细胞和FoxP3+调节性T细胞无变化，提示寄生虫可能存在不依赖于调节性T细胞的免疫调节作用。
