Kim Narae, Gu Min Jeong, Kye Yoon-Chul, Ju Young-Jun, Hong Rira, Ju Do Bin, Pyung Young Jin, Han Seung Hyun, Park Byung-Chul, Yun Cheol-Heui
Department of Agricultural Biotechnology, and Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, 08826, Republic of Korea.
Department of Oral Microbiology and Immunology, and Dental Research Institute, School of Dentistry, Seoul National University, Seoul, 08826, Republic of Korea.
Sci Rep. 2022 Jan 18;12(1):941. doi: 10.1038/s41598-022-04861-4.
Bacteriophages, simply phages, have long been used as a potential alternative to antibiotics for livestock due to their ability to specifically kill enterotoxigenic Escherichia coli (ETEC), which is a major cause of diarrhea in piglets. However, the control of ETEC infection by phages within intestinal epithelial cells, and their relationship with host immune responses, remain poorly understood. In this study, we evaluated the effect of phage EK99P-1 against ETEC K99-infected porcine intestinal epithelial cell line (IPEC-J2). Phage EK99P-1 prevented ETEC K99-induced barrier disruption by attenuating the increased permeability mediated by the loss of tight junction proteins such as zonula occludens-1 (ZO-1), occludin, and claudin-3. ETEC K99-induced inflammatory responses, such as interleukin (IL)-8 secretion, were decreased by treatment with phage EK99P-1. We used a IPEC-J2/peripheral blood mononuclear cell (PBMC) transwell co-culture system to investigate whether the modulation of barrier disruption and chemokine secretion by phage EK99P-1 in ETEC K99-infected IPEC-J2 would influence immune cells at the site of basolateral. The results showed that phage EK99P-1 reduced the mRNA expression of ETEC K99-induced pro-inflammatory cytokines, IL-1β and IL-8, from PBMC collected on the basolateral side. Together, these results suggest that phage EK99P-1 prevented ETEC K99-induced barrier dysfunction in IPEC-J2 and alleviated inflammation caused by ETEC K99 infection. Reinforcement of the intestinal barrier, such as regulation of permeability and cytokines, by phage EK99P-1 also modulates the immune cell inflammatory response.
噬菌体，简称 phages，长期以来一直被用作牲畜抗生素的潜在替代品，因为它们能够特异性杀死产肠毒素大肠杆菌（ETEC），而 ETEC 是仔猪腹泻的主要原因。然而，噬菌体在肠道上皮细胞内对 ETEC 感染的控制及其与宿主免疫反应的关系仍知之甚少。在本研究中，我们评估了噬菌体 EK99P-1 对 ETEC K99 感染的猪肠道上皮细胞系（IPEC-J2）的影响。噬菌体 EK99P-1 通过减弱由紧密连接蛋白如闭合蛋白-1（ZO-1）、闭合蛋白和紧密连接蛋白-3 丢失介导的通透性增加，预防了 ETEC K99 诱导的屏障破坏。用噬菌体 EK99P-1 处理可降低 ETEC K99 诱导的炎症反应，如白细胞介素（IL）-8 的分泌。我们使用 IPEC-J2/外周血单核细胞（PBMC）Transwell 共培养系统来研究噬菌体 EK99P-1 对 ETEC K99 感染的 IPEC-J2 中屏障破坏和趋化因子分泌的调节是否会影响基底外侧部位的免疫细胞。结果表明，噬菌体 EK99P-1 降低了基底外侧收集的 PBMC 中 ETEC K99 诱导的促炎细胞因子 IL-1β和 IL-8 的 mRNA 表达。总之，这些结果表明噬菌体 EK99P-1 预防了 ETEC K99 诱导的 IPEC-J2 屏障功能障碍，并减轻了 ETEC K99 感染引起的炎症。噬菌体 EK99P-1 对肠道屏障的增强作用，如通透性和细胞因子的调节，也调节了免疫细胞的炎症反应。
