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Updated: Aug 15, 2026
10:51
Isolation and Culture of Primary Mouse Keratinocytes from Neonatal and Adult Mouse Skin
Published on: July 14, 2017
Rapid modulation of keratinocyte differentiation by the external environment
The Journal of Investigative Dermatology
|April 1, 1983
Summary
Epidermal cell differentiation in vitro differs from in vivo. However, when injected into mice, cultured epidermal cells rapidly formed keratinization markers, demonstrating environmental modulation of cell differentiation.
Area of Science:
- Dermatology
- Cell Biology
- Tissue Engineering
Background:
- In vitro culture of epidermal keratinocytes with feeder cells alters their differentiation compared to in vivo epidermis.
- Key markers of keratinization, such as keratohyaline granules (KGs) and membrane-coating granules (MCGs), are absent in cultured cells.
Purpose of the Study:
- To investigate the in vivo differentiation potential of cultured rabbit epidermal cells.
- To determine if direct contact with a basement membrane is necessary for keratinization marker formation.
- To examine the reversibility and speed of differentiation modulation by the external environment.
Main Methods:
- Cultured rabbit epidermal cells were trypsinized and subcutaneously injected into athymic mice.
- The reaggregated cells formed cysts lined with stratified squamous epithelium.
- Electron microscopy was used to examine ultrastructural differentiation over 16 days.
Main Results:
- Within 24-48 hours, injected cells formed MCGs, KGs, and horny cells, independent of basement membrane formation.
- Glycogen and lipid droplets decreased in abundance during differentiation.
- By 16 days, the cystic epithelium ultrastructure resembled in vivo epidermis, including "rabbit-type" KGs and MCGs.
Conclusions:
- Epidermal cell differentiation is significantly and reversibly modulated by the external environment.
- The expression of morphologic keratinization markers (KGs, MCGs) is rapidly influenced by the growth environment.
- Direct contact with a continuous basal lamina is not required for the initial formation of keratinization markers.
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