Abstract
Abstract: :
Purpose:Bovine pituitary extract (BPE) has been used widely as the primary supplement in the serum-free culture system for epidermal keratinocytes. However, the composition of BPE is relatively undefined and the results thus obtained are difficult to interpret. Recent epidemic of bovine spongiform encephalopathy also poses potential risks of using BPE for clinical applications. To circumvent these drawbacks, we evaluated the effect of defined lipid supplements as BPE substitutes in serum-free media on epidermal and corneal keratinocytes. Methods:Human epidermal keratinocytes and rabbit corneal epithelial cells were harvested by dispase treatment and cultured in serum-free MCDB medium. BPE or lipid mixtures containing linoleic acid, vitamin E and several other essential lipids were added as medium supplements. Non-supplemented medium was used as a control. Effect of each supplement for cell proliferation was quantified by cytometry and the epithelial differentiation was evaluated with a battery of monoclonal anti-keratin antibodies. Results:For human epidermal keratinocytes, lipid-supplemented media supported cell proliferation significantly better than the control medium. When compared with BPE-supplemented media, lipid-containing media demonstrated equal or slightly better support of cell growth. For rabbit corneal epithelial cells, lipid-supplemented media also promoted cell growth at a level comparable to BPE-supplemented media. Normal keratin expression was noted in the human epidermal keratinocytes and rabbit corneal epithelial cells. The lipid supplements did not affect the epithelial differentiation as defined by keratin expression. Conclusion:The lipid-supplemented serum-free media facilitated the cell propagation in cultured human epidermal and rabbit corneal keratinocytes. The results indicate lipid supplements can be used as a viable alternative to BPE for serum-free keratinocyte cultures.
Keywords: 372 cornea: epithelium • 370 cornea: basic science • 492 nutritional factors