Pig fecal microbiota and vaccine response against the swine flu. Saphir IAV

Understanding and predicting why some animals respond better to vaccination than others is a main concern to strengthen vaccination efficiency. Our aim was to study whether the gut microbiota before vaccination presents composition patterns associated with individual variabilities of vaccine responses in pigs. 98 Large White piglets were vaccinated against the influenza A virus (IAV) at weaning at 28 days of age (D28) with a booster three weeks later. Stools were collected before the vaccination at D28, and were further processed to perform 16SRNA gene sequencing and assess microbial taxonomic composition. The piglets response was evaluated by ELISA of seric IAV-specific IgGs and by hemagglutination inhibition assays (HAI) at D49, D56, D63, and D146 to identify extreme animals with either high or low responses to vaccination. Piglets with a richer microbiota had higher levels of HAI at D63 and had a tendency towards more IAV-specific IgGs. Extreme high and low responders for IAV-specific IgGs at D63 had also a dissimilar microbiota and displayed differentially abundant operational taxonomic units OTUs; bacteria from the Paludibacteraceae family and Prevotella genera were more abundant in high responders, while bacteria from Helicobacter and Escherichia-Shigella genera were more abundant in low responders. Thus, our results show that the faecal microbiota before vaccination could be further investigated to identify biomarkers predictive of vaccine response levels and analyse the underlying biology.

阐明并预测为何部分动物的疫苗应答效果优于其他个体，是提升疫苗接种效力的核心关切之一。本研究旨在探究猪群在疫苗接种前的肠道菌群组成模式，是否与其个体间的疫苗应答差异存在关联。本研究选取98头大白仔猪，于28日龄（D28）断奶时接种甲型流感病毒（influenza A virus, IAV）疫苗，并于三周后实施加强免疫。于D28接种前采集粪便样本，后续通过16S rRNA基因测序技术分析微生物分类组成。分别于D49、D56、D63及D146四个时间点，通过血清甲型流感病毒特异性IgG酶联免疫吸附试验（ELISA）以及血凝抑制试验（hemagglutination inhibition assays, HAI）评估仔猪的疫苗应答水平，以此筛选出疫苗应答极高或极低的极端个体。肠道菌群丰富度更高的仔猪在D63时的HAI滴度更高，且其血清甲型流感病毒特异性IgG水平也呈现升高趋势。在D63时甲型流感病毒特异性IgG应答处于极端水平的仔猪，其肠道菌群组成同样存在显著差异，且存在丰度差异显著的操作分类单元（operational taxonomic units, OTUs）；高应答组仔猪体内的沼杆菌科（Paludibacteraceae）细菌及普雷沃氏菌属（Prevotella）丰度更高，而低应答组仔猪则更易检出螺杆菌属（Helicobacter）与埃希氏菌-志贺氏菌属（Escherichia-Shigella）细菌。综上，本研究结果表明，可进一步探究疫苗接种前的粪便菌群，以筛选可预测疫苗应答水平的生物标志物，并解析其背后的生物学机制。