Your new experience awaits. Try the new design now and help us make it even better

ORIGINAL RESEARCH article

Front. Microbiol.

Sec. Infectious Agents and Disease

Volume 16 - 2025 | doi: 10.3389/fmicb.2025.1631008

This article is part of the Research TopicZoonotic Diseases: Epidemiology, Multi-omics, and Host-pathogen Interactions Vol IIView all 3 articles

PipC Affects the Virulence of Salmonella enterica Serovar Enteritidis and Its Deletion Strain Provides Effective Immune Protection in Mice

Provisionally accepted
Lu  ZhangLu Zhang1Yubin  ChenYubin Chen1Zhigang  YanZhigang Yan2Yuntai  LiYuntai Li1Xiaowen  YangXiaowen Yang3Li  ChenLi Chen1Yanying  ZhangYanying Zhang1Yingyu  ChenYingyu Chen4Yonghui  LiYonghui Li5Qiumei  ShiQiumei Shi1Tonglei  WuTonglei Wu1*
  • 1Hebei Normal University of Science and Technology, Qinhuangdao, China
  • 2Hebei Provincial Center for Livestock Breeding Improvement, Shijiazhuang, China
  • 3Chinese Academy of Agricultural, Beijing, China
  • 4Huazhong Agricultural University, Wuhan, China
  • 5The second hospital of Qinhuangdao, Qinhuangdao, China

The final, formatted version of the article will be published soon.

Background: Salmonellosis caused by Salmonella sp. is a foodborne zoonotic disease that poses a significant threat to public health security. Vaccination is a safe and effective strategy for preventing and controlling Salmonella infections. PipC is a chaperone protein associated with Salmonella invasion proteins which is crucial for bacteria to invade host cells.In this study, a ΔpipC mutant strain was generated. Subsequently, we examined the environmental stress tolerance of the mutant strain through in vitro simulation experiments.Moreover, its virulence by employing cell and mouse infection models was investigated.Furthermore, we utilized a mouse model to further explore its potential as an attenuated live vaccine against Salmonella enterica serovar Enteritidis infection.The Salmonella strain C50336 with a deletion of the pipC gene exhibits a significant reduction in its ability to resist environmental stress and virulence. Meanwhile, the expression levels of SPI-1-related genes (invH, sipA, sipB, sipC, sopB, and sopE2) and SPI-2-related genes (spvB, ssrA, orf245, ssaS, ssaT, ssaU, sseB, and sseD) encoding the Salmonella type III secretion system (T3SS) were found to be decreased, leading to a significant reduction in the bacteria's invasion and intracellular survival abilities. The results of the mouse intraperitoneal challenge experiment showed that compared with the wild-type strain, the 50% lethal dose (LD50) of the ΔpipC strain increased by 47 times, and the bacterial loads in the liver, spleen, and cecum were significantly reduced. When mice were immunized with the ΔpipC mutant strain, the immunized mice showed a robust immune response, with significantly increased cytokine and antibody levels in their bodies.Mice vaccinated with the ΔpipC mutant strain had 100% immune protection against wild-type Salmonella infection.This study demonstrates that lack of pipC affects SE pathogenicity by decreasing its virulence both in vitro and in vivo. Vaccination of mice with ΔpipC conferred development of an acquired immunity and efficacious protection against experimental systemic infection. These results indicated that the ΔpipC mutant strain can be used in the development of attenuated live vaccines.

Keywords: Salmonella enterica serovar Enteritidis, PIPC, Virulence, immune protection, Vaccine

Received: 19 May 2025; Accepted: 03 Jun 2025.

Copyright: © 2025 Zhang, Chen, Yan, Li, Yang, Chen, Zhang, Chen, Li, Shi and Wu. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

* Correspondence: Tonglei Wu, Hebei Normal University of Science and Technology, Qinhuangdao, China

Disclaimer: All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.