ISSN:
1600-0625
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Medicine
Notes:
Abstract Keratinocytes propagated in low calcium (30 μM CaCl2) serum-free media grow in a monolayer and exhibit morphologic and biosynthetic phenolypes most similar to those of keratinocytes in the basal layer of the normal epidermis. When the calcium in the media is elevated to 1 mM. the cells stratify and differentiate. The effects of calcium on human foreskin keratinocyte expression of urokinase type (uPA) and tissue type (tPA) plasminogen activator enzymes and plasminogen activator inhibitor 1 and 2 (PAI-1, PAI-2) were assessed by Northern analyses. Our data show that keratinocytes, cultured in the presence of low and high CaCl2 concentrations, express transcripts for uPA and PAI-2. Message levels for uPA were dramatically reduced in cultures stimulated with calcium, whereas those for PA 1–2 were only slightly decreased. Little PAI-1 mRNA and no tPA mRNA were detected, independent of calcium levels. Aclin mRNA levels were not modulated consequent to calcium stimulation. Hybridizations to 28S ribosomal RNA confirmed that equal amounts of RNA were analyzed from cells grown under low and high calcium conditions. These data demonstrate that keratinocytes. propagated in serum-free media under low and high calcium conditions, are similar to normal human epidermis with respect to their expression of regulators of plasminogen activation. Additionally, they suggest that the ratio of PAI-2 to uPA increases with keratinocyte differentiation.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1600-0625.1994.tb00052.x
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