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Updated: May 8, 2026
08:19
Evaluation of Keratinocyte Proliferation on Two- and Three-dimensional Type I Collagen Substrates
Published on: April 22, 2019
Platelet-activating factor induces proliferation in differentiated keratinocytes
Astrid J Feuerherm1, Katarina M Jørgensen, Randi M Sommerfelt
1Department of Biology, Norwegian University of Science and Technology (NTNU), Trondheim, Norway.
Molecular and Cellular Biochemistry
|August 27, 2013
Summary
Platelet-activating factor (PAF) stimulates keratinocyte proliferation and epidermal repair, not inflammation. This suggests PAF connects inflammation to proliferation in skin healing.
Area of Science:
- Dermatology
- Cell Biology
- Molecular Biology
Background:
- Platelet-activating factor (PAF) is elevated in inflammatory skin conditions.
- The precise function of PAF in epidermal biology remains unclear.
Purpose of the Study:
- To investigate the gene regulatory effects of PAF on differentiated keratinocytes.
- To elucidate the role of PAF in epidermal wound healing processes.
Main Methods:
- Transcriptional profiling of HaCaT keratinocytes stimulated with PAF.
- Analysis of phosphorylated kinases.
- In vitro wound-scratch assays.
- Resazurin assay and flow cytometry for cell cycle analysis.
Main Results:
- PAF stimulation primarily affects genes involved in proliferation, apoptosis, and migration.
- PAF induces COX2 expression but regulates few inflammation-associated genes in keratinocytes.
- Experimental data support PAF's role in keratinocyte proliferation and epidermal re-epithelialization.
Conclusions:
- PAF acts as a proliferation activator in differentiated keratinocytes.
- PAF may bridge the gap between inflammation and proliferation during skin repair.
- These findings offer new insights into the mechanisms of epidermal wound healing.
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