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Updated: Apr 18, 2026

Cultivating a Three-dimensional Reconstructed Human Epidermis at a Large Scale
Published on: May 28, 2021
The association of lipids with keratinous proteins of human callus
1Department of Medicine, The Johns Hopkins University, Baltimore, MD, USA.
Abstract:
1. Small amounts of phospholipids and cho- lesterol bound to major callus protein fractions during extraction have been quantitated. 2. Extraction with chloroform/methanol abolishes the requirement of these protein fractions for prolonged acid hydrolysis in order to release completely certain amino acid residues. 3. The binding capacity of lipid-free, isolated, keratinous proteins for cholesterol has been studied. 4. A plausible (though unproven) role for phospholipids, cholesterol, and keratin in the barrier functions of epidermis is re-emphasized.
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