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Updated: May 5, 2026
14:29
Visualization of Bacterial Toxin Induced Responses Using Live Cell Fluorescence Microscopy
Published on: October 1, 2012
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Intestinal tissue response to Shiga toxin exposure.
Kendal L Hanson1, Alison Ann Weiss1
1Department of Molecular and Cellular Biosciences, University of Cincinnati, Cincinnati, Ohio, USA.
Mbio
|August 13, 2024
Summary
Mesenchymal cells, not epithelial cells, are sensitive to Shiga toxin 2 (Stx2) in human intestinal models. This sensitivity contributes to epithelial cell death, highlighting the importance of tissue interactions in host-pathogen studies.
Area of Science:
- Microbiology
- Cell Biology
- Gastroenterology
Background:
- Shiga toxin (Stx)-producing *Escherichia coli* are pathogenic bacteria.
- Human intestinal organoids and enteroid monolayers (HIEMs) are used to model the human intestine.
- Mesenchymal cells interact with the intestinal epithelium.
Purpose of the Study:
- To investigate the impact of Shiga toxin (Stx) on the human intestine using HIEMs.
- To establish optimal experimental conditions for modeling host-pathogen interactions in vitro.
- To understand the role of mesenchymal cells in epithelial response to Stx.
Main Methods:
- Human intestinal enteroid monolayers (HIEMs) were cultured with or without mesenchymal cells.
- Transepithelial electrical resistance (TEER) was measured to assess monolayer integrity.
- HIEMs were exposed to Stx2 apically and/or basolaterally.
Main Results:
- Mesenchymal cells maintained epithelial monolayers in the absence of growth factors, suggesting they produce essential factors.
- Epithelial cells were more resistant to Stx2 than mesenchymal cells.
- Mesenchymal cell sensitivity to Stx2 contributed to epithelial cell death, and Stx2 traversed the intact epithelium.
Conclusions:
- Complex cell culture models are essential for studying host-pathogen interactions.
- Mesenchymal cells play a critical role in the epithelial response to Stx2.
- Understanding tissue interactions is crucial for determining pathogen effects on human tissues.
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