Bricarello P A, Zaros L G, Coutinho L L, Rocha R A, Silva M B, Kooyman F N J, De Vries E, Yatsuda A P, Amarante A F T
UNESP-Universidade Estadual Paulista, Departamento de Parasitologia, Instituto de Biociências, Caixa Postal 510, Botucatu CEP 18618-000, SP, Brazil.
Vet Parasitol. 2008 Aug 1;155(1-2):95-103. doi: 10.1016/j.vetpar.2008.03.016. Epub 2008 Apr 4.
Cellular and humoral immune response, as well as cytokine gene expression, was assessed in Nelore cattle with different degrees of resistance to Cooperia punctata natural infection. One hundred cattle (male, weaned, 11-12 months old), kept together on pasture, were evaluated. Faecal and blood samples were collected for parasitological and immunological assays. Based on nematode faecal egg counts (FEC) and worm burden, the seven most resistant and the eight most susceptible animals were selected. Tissue samples of the small intestine were collected for histological quantification of inflammatory cells and analysis of cytokine gene expression (IL-2, IL-4, IL-8, IL-12p35, IL-13, TNF-alpha, IFN-gamma, MCP-1, MCP-2, and MUC-1) using real-time RT-PCR. Mucus samples were also collected for IgA levels determination. Serum IgG1 mean levels against C. punctata antigens were higher in the resistant group, but significant differences between groups were only observed 14 days after the beginning of the experiment against infective larvae (L3) and 14 and 84 days against adult antigens. The resistant group also presented higher IgA levels against C. punctata (L3 and adult) antigens with significant difference 14 days after the beginning of the trial (P<0.05). In the small-intestine mucosa, levels of IgA anti-L3 and anti-adult C. punctata were higher in the resistant group, compared with the susceptible group (P<0.05). Gene expression of both T(H)2 cytokines (IL-4 and IL-13) in the resistant group and T(H)1 cytokines (IL-2, IL-12p35, IFN-gamma and MCP-1) in the susceptible group was up-regulated. Such results suggested that immune response to C. punctata was probably mediated by T(H)2 cytokines in the resistant group and by T(H)1 cytokines in the susceptible group.
对感染微小库珀线虫具有不同抗性程度的内洛尔牛的细胞免疫和体液免疫反应以及细胞因子基因表达进行了评估。对在牧场上一起饲养的100头断奶雄性牛（11 - 12月龄）进行了评估。采集粪便和血液样本用于寄生虫学和免疫学检测。根据线虫粪便虫卵计数（FEC）和虫体负荷，挑选出7头抗性最强和8头易感性最高的动物。采集小肠组织样本，用于炎症细胞的组织学定量分析以及使用实时逆转录聚合酶链反应分析细胞因子基因表达（IL - 2、IL - 4、IL - 8、IL - 12p35、IL - 13、肿瘤坏死因子 - α、干扰素 - γ、单核细胞趋化蛋白 - 1、单核细胞趋化蛋白 - 2和黏蛋白 - 1）。还采集黏液样本用于测定IgA水平。抗性组针对微小库珀线虫抗原的血清IgG1平均水平较高，但仅在实验开始后14天针对感染性幼虫（L3）以及14天和84天针对成虫抗原时，两组之间才观察到显著差异。抗性组针对微小库珀线虫（L3和成虫）抗原的IgA水平也较高，在试验开始后14天差异显著（P<0.05）。在小肠黏膜中，与易感组相比，抗性组抗L3和抗成虫微小库珀线虫的IgA水平更高（P<0.05）。抗性组中T(H)2细胞因子（IL - 4和IL - 13）以及易感组中T(H)1细胞因子（IL - 2、IL - 12p35、干扰素 - γ和单核细胞趋化蛋白 - 1）的基因表达均上调。这些结果表明，抗性组中对微小库珀线虫的免疫反应可能由T(H)2细胞因子介导，而易感组中则由T(H)1细胞因子介导。
