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Updated: Jun 24, 2026
08:19
Evaluation of Keratinocyte Proliferation on Two- and Three-dimensional Type I Collagen Substrates
Published on: April 22, 2019
IGF-II and collagen expression by keratocytes during postnatal development.
Bradley P Kane1, James V Jester, Jiying Huang
1Department of Molecular Medicine, College of Medicine, University of South Florida, Tampa, FL 33612-4799, USA.
Experimental Eye Research
|March 31, 2009
Summary
Keratinocyte biosynthetic activity declines with age. Neonatal keratinocytes, unlike adult ones, show high expression of growth factors and collagen, suggesting a role in early corneal development.
Area of Science:
- Ophthalmology
- Developmental Biology
- Cell Biology
Background:
- Keratocytes are crucial for corneal matrix production during development.
- Understanding age-related changes in keratocyte function is vital for corneal health.
Purpose of the Study:
- To investigate the hypothesis that keratocyte biosynthetic activity declines during development.
- To compare the proliferative and collagen synthesis capabilities of young and aged keratocytes.
Main Methods:
- Keratocytes were isolated from rabbit and cow corneas.
- Cell proliferation and collagen synthesis were assessed in vitro.
- Microarray analysis of neonatal and adult mouse keratocyte mRNA was performed.
Main Results:
- Rabbit keratocytes proliferated and produced collagen type I and IGF-II.
- Bovine keratocytes showed limited proliferation and no detectable collagen or IGF-II.
- Conditioned media from rabbit keratocytes stimulated bovine keratocyte proliferation and collagen synthesis.
- Neonatal mouse keratocytes exhibited higher expression of IGFs and collagens compared to adult keratocytes.
Conclusions:
- Keratocyte biosynthetic activity, particularly collagen and IGF production, decreases with age.
- Insulin-like growth factors (IGFs) are likely key regulators of early corneal growth in vivo.
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