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Updated: Aug 25, 2026

Generation and Culturing of Primary Human Keratinocytes from Adult Skin
10:42

Generation and Culturing of Primary Human Keratinocytes from Adult Skin

Published on: December 22, 2017

Functional down-regulation of alpha 5 beta 1 integrin in keratinocytes is reversible but commitment to terminal

N A Hotchin1, N L Kovach, F M Watt

  • 1Keratinocyte Laboratory, Imperial Cancer Research Fund, Lincoln's Inn Fields, London, UK.

Journal of Cell Science
|December 1, 1993
PubMed

Insights

The alpha 5 beta 1 integrin

Area of Science:

  • Dermatology
  • Cell Biology
  • Biochemistry

Background:

  • Integrins, extracellular matrix receptors, regulate epidermal adhesion and differentiation.
  • Loss of cell-matrix contact in keratinocytes induces terminal differentiation and reduces alpha 5 beta 1 integrin's fibronectin binding.
  • The reversibility of this process is investigated.

Purpose of the Study:

  • To determine if the reduced ligand-binding ability of alpha 5 beta 1 integrin is reversible.
  • To investigate if keratinocyte terminal differentiation commitment can be reversed.

Main Methods:

  • Keratinocytes were cultured in suspension for 5 hours to induce differentiation commitment.
  • An activating anti-beta 1 antibody (8A2) was used to assess alpha 5 beta 1 integrin function.
  • Fibronectin-Sepharose binding assays and cell adhesion assays were performed.
  • The role of divalent cations (Ca2+, Mg2+, Mn2+) was examined.

Main Results:

  • The activating antibody 8A2 restored alpha 5 beta 1 integrin's fibronectin-binding ability in suspended keratinocytes.
  • 8A2 also rescued alpha 5 beta 1 integrin function in cell adhesion assays.
  • While 8A2's effect was calcium-dependent, it did not prevent keratinocyte cell cycle withdrawal or involucrin expression.

Conclusions:

  • The ligand-binding capacity of alpha 5 beta 1 integrin is reversible upon activation.
  • However, restoring integrin function does not reverse the commitment of keratinocytes to terminal differentiation.

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