Open AccessKinetics of the calcium induced stratification of human keratinocytes in vitro
Author(s) -
Heenen M.,
Graef Ch. De,
Galand P
Publication year - 1992
Publication title -
cell proliferation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.647
H-Index - 74
eISSN - 1365-2184
pISSN - 0960-7722
DOI - 10.1111/j.1365-2184.1992.tb01398.x
Subject(s) - involucrin , mitosis , keratinocyte , calcium , in vitro , biology , thymidine , cell cycle , cell , microbiology and biotechnology , biophysics , chemistry , biochemistry , organic chemistry
. In a low concentration of calcium (0.1 mM), keratinocytes form a monolayer with about 30% of cells synthesizing involucrin. After addition of calcium to the culture medium to a concentration of 1.2 mM, the monolayer stratifies within 24 h, with a preferential migration of involucrin positive keratinocytes. In the present study, we tried to determine if keratinocytes control the decision to migrate at a distinct cell cycle point. A percentage labelled mitosis (PLM) curve was constructed for keratinocytes grown in low calcium medium and values for the length of the cell cycle (47 h), S phase duration (11 h) and G 2 + M period (6 h), were obtained. Monolayer cultures at 80% confluence were switched to high calcium concentration at various times (from 0 to 48 h), after pulse labelling with [ 3 H]‐thymidine. Based on the PLM data, the behaviour of cells known to be in S, G 1 and G 2 at the time of the migration stimulus were followed. No significant difference in the percentage of labelled suprabasal cells was found for any point of the cell cycle. For cells submitting to stratification, in S phase involucrin staining showed that about 60% of the [ 3 H]‐thymidine labelled cells were also involucrin negative. These results indicate that upward migration of keratinocytes in cultured epithelium can be triggered at all points in the cell cycle with equal probability and is not restricted to those cells that already contained involucrin.