Department of Veterinary Medicine, University of Cambridge, Cambridge, UK.
Departament de Farmàcia I Tecnologia Farmacèutica I Parasitologia, Facultat de Farmàcia, Universitat de València, Valencia, Spain.
Parasit Vectors. 2021 Apr 6;14(1):189. doi: 10.1186/s13071-021-04688-4.
Growing evidence points towards a role of gastrointestinal (GI) helminth parasites of ruminants in modifying the composition of the host gut flora, with likely repercussions on the pathophysiology of worm infection and disease, and on animal growth and productivity. However, a thorough understanding of the mechanisms governing helminth-microbiota interactions and of their impact on host health and welfare relies on reproducibility and replicability of findings. To this aim, in this study, we analysed quantitative and qualitative fluctuations in the faecal microbiota composition of lambs vaccinated against, and experimentally infected with, the parasitic GI nematode Teladorsagia circumcincta over the course of two separate trials performed over two consecutive years.
Two trials were conducted under similar experimental conditions in 2017 and 2018, respectively. In each trial, lambs were randomly assigned to one of the following experimental groups: (i) vaccinated/infected, (ii) unvaccinated/infected and (iii) unvaccinated/uninfected. Faecal samples collected from individual animals were subjected to DNA extraction followed by high-throughput sequencing of the V3-V4 region of the bacterial 16S rRNA gene and bioinformatics and biostatistical analyses of sequence data.
Substantial differences in the populations of bacteria affected by immunisation against and infection by T. circumcincta were detected when comparing data from the two trials. Nevertheless, the abundance of Prevotella spp. was significantly linked to helminth infection in both trials.
Despite the largely conflicting findings between the two trials, our data revealed that selected gut microbial populations are consistently affected by T. circumcincta infection and/or vaccination. Nevertheless, our study calls for caution when interpreting data generated from in vivo helminth-microbiome interaction studies that may be influenced by several intrinsic and extrinsic host-, parasite- and environment-related factors.
越来越多的证据表明，反刍动物的胃肠道（GI）寄生虫在改变宿主肠道菌群组成方面发挥作用，这可能对蠕虫感染和疾病的病理生理学以及动物生长和生产力产生影响。然而，要全面了解寄生虫-微生物群相互作用的机制及其对宿主健康和福利的影响，就需要对研究结果进行可重复性和可复制性验证。为此，本研究在两年内连续进行了两次独立试验，分析了接种和实验感染寄生性 GI 线虫捻转血矛线虫的羔羊粪便微生物群组成的定量和定性波动。
2017 年和 2018 年分别进行了两项试验，实验条件相似。在每个试验中，羔羊随机分配到以下实验分组之一：（i）接种/感染、（ii）未接种/感染和（iii）未接种/未感染。从个体动物收集的粪便样本进行 DNA 提取，然后对细菌 16S rRNA 基因的 V3-V4 区进行高通量测序，并对序列数据进行生物信息学和生物统计学分析。
当比较两次试验的数据时，发现针对 T. circumcincta 免疫接种和感染对细菌种群的影响存在显著差异。然而，在两次试验中，Prevotella spp.的丰度均与蠕虫感染显著相关。
尽管两次试验的结果存在很大差异，但我们的数据表明，一些肠道微生物群会受到捻转血矛线虫感染和/或疫苗接种的持续影响。然而，我们的研究呼吁在解释体内寄生虫-微生物组相互作用研究的数据时要谨慎，这些数据可能会受到宿主、寄生虫和环境相关因素的内在和外在影响。
