In vitro assessment of keratinocyte aging

J Invest Dermatol. 1983 Jul;81(1 Suppl):184s-9s. doi: 10.1111/1523-1747.ep12541084.

Abstract

In vitro aging models are based on the observation that normal cells in culture have a finite lifespan and eventually cease to proliferate under conditions that initially support excellent growth. Recent assessment of the aging process in keratinocytes, made possible by improved tissue-culture techniques, have confirmed prior findings with fetal and adult fibroblasts and have permitted investigation into the mechanism of in vitro senescence. Early-passage newborn human keratinocytes maintained in a serum-free system were found to proliferate more rapidly than early-passage adult keratinocytes maintained under identical conditions, and they were also found to have far steeper dose-response curves for a potent hypothalamus-derived mitogen keratinocyte growth factor (KGF), as well as for KGF/EGF in combination, with a more than 200-fold increase in cell number, total protein, and colony size over the tested range of concentrations, as opposed to a less than 75-fold increase for adult keratinocytes in these parameters. These results support the hypothesis that the age-associated decrease for keratinocyte proliferation in vitro may be due to progressive loss of mitogenic responsiveness. Unrecognized changes in proliferative rate and growth-factor requirements related to age of the tissue donor may complicate interpretation of studies addressing other aspects of keratinocyte biology.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Cell Division / drug effects
  • Cell Survival
  • Dose-Response Relationship, Drug
  • Epidermal Cells*
  • Epidermal Growth Factor / pharmacology
  • Fibroblasts / cytology
  • Humans
  • Infant, Newborn
  • Models, Biological

Substances

  • Epidermal Growth Factor