Salmonella Outer Protein B Suppresses Colitis Development via Protecting Cell From Necroptosis

• Published in: Frontiers in cellular and infection microbiology Vol. 9; p. 87
• Main Authors: Hu, Gui-Qiu, Yang, Yong-Jun, Qin, Xiao-Xia, Qi, Shuai, Zhang, Jie, Yu, Shui-Xing, Du, Chong-Tao, Chen, Wei
• Format: Journal Article
• Language: English
• Published: Switzerland Frontiers Media S.A 09.04.2019
• Subjects: Animals; Bacterial Proteins - genetics; Bacterial Proteins - metabolism; Bacterial Translocation; Cell Line; Cellular and Infection Microbiology; colitis; Colitis - microbiology; Colitis - pathology; Disease Models, Animal; Gene Deletion; Goblet Cells - microbiology; Goblet Cells - physiology; Host-Pathogen Interactions; Humans; Mice, Inbred C57BL; Mice, Knockout; MLKL; necroptosis; Necroptosis - drug effects; Salmonella; Salmonella Infections - pathology; SopB; Virulence Factors - deficiency; Virulence Factors - metabolism; Salmonella; SopB; colitis; MLKL; necroptosis
• ISSN: 2235-2988; 2235-2988
• DOI: 10.3389/fcimb.2019.00087

effectors translocated into epithelial cells contribute to the pathogenesis of infection. They mediate epithelial cell invasion and subsequent intracellular replication. However, their functions have not been well-identified. In this study, we uncovered a role for outer protein B (SopB) in modulating necroptosis to facilitate bacteria escape epithelial cell and spread to systemic sites through a -induced colitis model. Mice infected with SopB deleted strain Δ displayed increased severity to colitis, reduced mucin expression and increased bacterial translocation. study, we found there was an increased goblet cell necroptosis following Δ infection. Consistently, mice infected with Δ had a strong upregulation of mixed lineage kinase domain-like (MLKL) phosphorylation. Deletion of MLKL rescued severity of tissue inflammatory, improved mucin2 expression and abolished the increased bacterial translocation in mice infected with Δ . Intriguingly, the expression of in LS174T cells was downregulated. The temporally regulated SopB expression potentially switched the role from epithelial cell invasion to bacterial transmission. Collectively, these results indicated a role for SopB in modulating the onset of necroptosis to increased bacteria pathogenesis and translocated to systemic sites.