Campylobacter is a leading causative pathogen of acute bacterial gastroenteritis among humans. Contaminated chicken products are regarded as major sources of human infection. The flagellar capping protein (FliD), which plays important roles in colonization and adhesion to the mucosal surface of chicken caeca, is conserved among Campylobacter jejuni strains. In this study, the recombinant C. jejuni FliD protein was expressed, purified, and used as a coated protein to examine the prevalence of C. jejuni antibodies in chickens. The anti-FliD antibody was prevalent among chicken serum samples taken from different farms in the diverse regions of Jiangsu Province by using ELISA assay. The Campylobacter antibody was present in culture-negative chickens. No strong dose–response relationships were observed between serum FliD antibody levels and Campylobacter cultural status. These results provide a basis for further evaluating FliD as a vaccine candidate for broiler chickens or for examining host–C. jejuni interactions, with implications for improving food safety.

中文翻译：

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空肠弯曲杆菌 FliD 蛋白的表达及其对鸡血清的反应。

弯曲杆菌是人类急性细菌性胃肠炎的主要病原体。受污染的鸡肉产品被认为是人类感染的主要来源。鞭毛加帽蛋白 (FliD) 在鸡盲肠黏膜表面的定植和粘附中起重要作用，在空肠弯曲杆菌菌株中是保守的。在这项研究中，重组空肠弯曲杆菌FliD 蛋白被表达、纯化并用作包被蛋白，以检查鸡中空肠弯曲杆菌抗体的流行情况。通过ELISA检测，在江苏省不同地区不同农场采集的鸡血清样本中普遍存在抗FliD抗体。该弯曲杆菌培养阴性的鸡中存在抗体。在血清 FliD 抗体水平和弯曲杆菌培养状态之间没有观察到强的剂量反应关系。这些结果为进一步评估 FliD 作为肉鸡候选疫苗或检查宿主与空肠弯曲杆菌的相互作用提供了基础，对改善食品安全有影响。