Department of Poultry Science, Mississippi State University, Mississippi State, MS 39762, USA.
Institute for Genomics, Biocomputing, and Biotechnology, Mississippi State University, Mississippi State, MS 39762, USA.
Poult Sci. 2023 May;102(5):102592. doi: 10.1016/j.psj.2023.102592. Epub 2023 Feb 15.
Campylobacter jejuni (C. jejuni) is the most common food-borne pathogen that causes human gastroenteritis in the United States. Consumption of contaminated poultry products is considered as the major source of human Campylobacter infection. An effective vaccine would be a promising alternative to antibiotic supplements to curb C. jejuni colonization in poultry gastrointestinal (GI) tract. However, the genetic diversity among the C. jejuni isolates makes vaccine production more challenging. Despite many attempts, an effective Campylobacter vaccine is not yet available. This study aimed to identify suitable candidates to develop a subunit vaccine against C. jejuni, which could reduce colonization in the GI tract of the poultry. In the current study, 4 C. jejuni strains were isolated from retail chicken meat and poultry litter samples and their genomes were sequenced utilizing next-generation sequencing technology. The genomic sequences of C. jejuni strains were screened to identify potential antigens utilizing the reverse vaccinology approach. In silico genome analysis predicted 3 conserved potential vaccine candidates (phospholipase A [PldA], TonB dependent vitamin B12 transporter [BtuB], and cytolethal distending toxin subunit B [CdtB]) suitable for the development of a vaccine. Furthermore, the expression of predicted genes during host-pathogen interaction was analyzed by an infection study using an avian macrophage-like immortalized cell line (HD11). The HD11 was infected with C. jejuni strains, and the RT-qPCR assay was performed to determine the expression of the predicted genes. The expression difference was analyzed using ΔΔCt methods. The results indicate that all 3 predicted genes, PldA, BtuB, and CdtB, were upregulated in 4 tested C. jejuni strains irrespective of their sources of isolation. In conclusion, in silico prediction and gene expression analysis during host-pathogen interactions identified 3 potential vaccine candidates for C. jejuni.
空肠弯曲菌（C. jejuni）是美国最常见的食源性病原体，可引起人类肠胃炎。食用受污染的家禽产品被认为是人类弯曲菌感染的主要来源。有效的疫苗将是替代抗生素补充剂来抑制家禽胃肠道（GI）中弯曲菌定植的有前途的方法。然而，弯曲菌分离株之间的遗传多样性使得疫苗生产更加具有挑战性。尽管进行了许多尝试，但仍没有有效的弯曲菌疫苗。本研究旨在确定合适的候选物，以开发针对 C. jejuni 的亚单位疫苗，从而减少家禽 GI 道中的定植。在本研究中，从零售鸡肉和家禽粪便样本中分离出 4 株 C. jejuni 菌株，并利用下一代测序技术对其基因组进行测序。利用反向疫苗学方法筛选 C. jejuni 菌株的基因组序列，以鉴定潜在的抗原。计算机基因组分析预测了 3 种保守的潜在疫苗候选物（磷脂酶 A [PldA]、TonB 依赖性维生素 B12 转运蛋白 [BtuB]和细胞致死扩张毒素亚基 B [CdtB]），适合开发疫苗。此外，通过使用禽巨噬细胞样永生化细胞系（HD11）进行感染研究，分析预测基因在宿主-病原体相互作用期间的表达。HD11 被 C. jejuni 菌株感染，然后进行 RT-qPCR 检测以确定预测基因的表达。使用 ΔΔCt 方法分析表达差异。结果表明，在所测试的 4 株 C. jejuni 菌株中，所有 3 个预测基因（PldA、BtuB 和 CdtB）均上调，而与它们的分离源无关。总之，宿主-病原体相互作用过程中的计算机预测和基因表达分析确定了 3 种空肠弯曲菌潜在的疫苗候选物。
