Heat-Stable Enterotoxins of Enterotoxigenic Escherichia coli and Their Impact on Host Immunity.

Haixiu Wang,Eric Cox,Zifu Zhong,Yu Luo,Bert Devriendt

doi:10.3390/toxins11010024

Haixiu Wang, Eric Cox + Show 3 more

Open Access

https://doi.org/10.3390/toxins11010024

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Journal: Toxins	Publication Date: Jan 8, 2019
Citations: 67	License type: CC BY 4.0

Affiliation: Ghent University, Jinhua Polytechnic

Abstract

Enterotoxigenic Escherichia coli (ETEC) are an important diarrhea-causing pathogen and are regarded as a global threat for humans and farm animals. ETEC possess several virulence factors to infect its host, including colonization factors and enterotoxins. Production of heat-stable enterotoxins (STs) by most ETEC plays an essential role in triggering diarrhea and ETEC pathogenesis. In this review, we summarize the heat-stable enterotoxins of ETEC strains from different species as well as the molecular mechanisms used by these heat-stable enterotoxins to trigger diarrhea. As recently described, intestinal epithelial cells are important modulators of the intestinal immune system. Thus, we also discuss the impact of the heat-stable enterotoxins on this role of the intestinal epithelium and how these enterotoxins might affect intestinal immune cells. Finally, the latest developments in vaccination strategies to protect against infections with ST secreting ETEC strains are discussed. This review might inform and guide future research on heat-stable enterotoxins to further unravel their molecular pathogenesis, as well as to accelerate vaccine design.

Highlights

Enterotoxigenic Escherichia coli (ETEC) are a common cause of acute diarrheal disease in both humans and farm animals [1,2,3]
Key Contribution: We summarize existing knowledge of heat-stable enterotoxins of ETEC strains and the development of related vaccination strategies
Enterotoxigenic Escherichia coli (ETEC) infections are an important cause of diarrhea in travelers, children under the age of five years, neonatal farm animals and post-weaning piglets

Summary

Introduction

Enterotoxigenic Escherichia coli (ETEC) are a common cause of acute diarrheal disease in both humans and farm animals [1,2,3]. ETEC infections are mainly reported in neonatal cattle and piglets. Enterotoxin LTI has two variants isolated from human (LT-Ih) and porcine (LT-Ip) strains, which elicit diarrhea, and improve the adherence of ETEC strains and other pathogens to the intestinal epithelium [22,23,24,25]. We will focus on the current knowledge on the role of the heat-stable enterotoxins in ETEC pathogenesis, their impact on host immunity, and the development of vaccines targeting ST-induced diarrhea

Heat-Stable Enterotoxins of ETEC from Human and Animal Origin

Secretion

Molecular

Impact on Enterocytes and the Intestinal Immune System

STs-Based Vaccines to Combat Human and Animal ETEC Induced Diarrhea

Findings

Conclusions