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Updated: Jun 11, 2025
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Induction and Analysis of Epithelial to Mesenchymal Transition
Published on: August 27, 2013
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TLR3 activation mediates partial epithelial-to-mesenchymal transition in human keratinocytes
Andrea M Schneider1, Robert P Feehan1, Mackenzie L Sennett1
1Department of Dermatology, Penn State Health Hershey Medical Center, Hershey, PA, USA.
Life Science Alliance
|September 30, 2024
Summary
Toll-like receptor 3 (TLR3) activation in human skin keratinocytes by UVB or poly(I:C) triggers epithelial-to-mesenchymal transition. This suggests TLR3 signaling influences skin development and regeneration beyond immunity.
Area of Science:
- Dermatology
- Immunology
- Cell Biology
Background:
- Toll-like receptor 3 (TLR3) is present in human skin keratinocytes.
- TLR3 plays a role in skin inflammation, development, and regeneration.
- Understanding TLR3's cellular response in keratinocytes is crucial.
Purpose of the Study:
- To investigate the cellular response of normal human keratinocytes to TLR3 activation.
- To examine the effects of both physiological (UVB) and synthetic (poly(I:C)) TLR3 activators.
Main Methods:
- Primary human keratinocytes were treated with UVB and poly(I:C).
- Morphological changes and gene expression related to epithelial-to-mesenchymal transition (EMT) were analyzed.
- Cell migration and invasion assays were performed.
Main Results:
- TLR3 activation by UVB or poly(I:C) induced significant changes in keratinocyte morphology.
- Key features of epithelial-to-mesenchymal transition (EMT) were observed, including increased gene expression, migration, and invasion.
- These changes indicate a role for TLR3 in regulating stem cell-like properties.
Conclusions:
- TLR3 signaling in keratinocytes promotes EMT, affecting cell migration and invasion.
- Beyond its immune function, TLR3 activation influences developmental programs in skin.
- These findings highlight TLR3's role in skin regeneration and stem cell regulation.
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