GVB - Viral Genetics and Biosafety Unit, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), Ploufragan, France; HQPAP - Unit of Hygiene and Quality of Poultry and Pork Products, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), Ploufragan, France; UFR of Life Sciences Environment, University of Rennes 1, Rennes, France.
GVB - Viral Genetics and Biosafety Unit, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), Ploufragan, France.
Poult Sci. 2023 Apr;102(4):102510. doi: 10.1016/j.psj.2023.102510. Epub 2023 Jan 20.
Campylobacter infections traced mainly to poultry products are major bacterial foodborne zoonoses. Among the many control strategies evaluated at primary poultry level to reduce these infections, vaccination could be a solution, but no effective vaccines are available to date. A better understanding of the immune mechanisms involved in protection against Campylobacter would be helpful for designing novel vaccine strategies. The present study was designed to analyze in more depth the immune responses developed in broilers in order to potentially identify which immune parameters may be important for establishing protection against Campylobacter by comparing the immune responses obtained here with those obtained in a previous study performed on vaccinated specific-pathogen-free Leghorn chickens that presented a partial reduction of Campylobacter after experimental challenge. The protection against Campylobacter colonization was evaluated at different time points over 40 d of rearing, by measuring specific IgY levels in serum and IgA antibodies in bile reflecting the systemic and mucosal humoral responses respectively and the relative expressions of 9 cecal immune marker genes (cytokines and antimicrobial peptides), which reflect the innate and cellular immune responses. Despite no reduction of Campylobacter in the cecum, a systemic immune response over time characterized by the production of specific anti-flagellin IgY was observed, in addition to upregulation of the antimicrobial peptide avian β-defensin (AvBD) 12 gene expression in the cecum of vaccinated broilers compared with the placebo group. However, the levels of specific anti-flagellin mucosal IgA antibodies in the bile as well as the relative expression of other cecal cytokines studied was underexpressed in the vaccinated group or similar in both groups.
空肠弯曲菌感染主要源于家禽产品，是主要的细菌性食源性人畜共患病。在初级家禽层面评估的许多控制策略中，疫苗接种可能是一种解决方案，但迄今为止尚无有效的疫苗。更好地了解针对空肠弯曲菌的保护所涉及的免疫机制将有助于设计新的疫苗策略。本研究旨在更深入地分析肉鸡中产生的免疫反应，以期通过比较在此处获得的免疫反应与在之前进行的针对接种无特定病原体莱亨鸡的研究中获得的免疫反应，潜在地确定哪些免疫参数可能对建立针对空肠弯曲菌的保护作用很重要。在 40 天的饲养过程中，通过测量血清中的特异性 IgY 水平和胆汁中的 IgA 抗体（分别反映系统和粘膜体液反应）以及 9 个盲肠免疫标记基因（细胞因子和抗菌肽）的相对表达水平，评估了针对空肠弯曲菌定植的保护作用。尽管盲肠中没有减少空肠弯曲菌，但观察到随着时间的推移产生针对鞭毛蛋白的特异性 IgY 的全身性免疫反应，此外与安慰剂组相比，接种疫苗的肉鸡盲肠中抗菌肽禽β-防御素（AvBD）12 基因的表达上调。然而，在接种组中，胆汁中针对鞭毛蛋白的特异性粘膜 IgA 抗体水平以及研究的其他盲肠细胞因子的相对表达水平较低，或者在两组中相似。
