Sh. Leir et al., Increased CD44 expression in human bronchial epithelial repair after damage or plating at low cell densities, AM J P-LUNG, 278(6), 2000, pp. L1129-L1137
Citations number
48
Categorie Soggetti
da verificare
Journal title
AMERICAN JOURNAL OF PHYSIOLOGY-LUNG CELLULAR AND MOLECULAR PHYSIOLOGY
We have investigated the effect of mechanical damage, cell density, and cel
l-derived soluble mediators on CD44 expression in a model of bronchial epit
helial repair. CD44 (all isoforms) and variant-containing isoforms (CD44v3,
CD44v6, and CD44v9) were identified with flow cytometry and immunocytochem
istry with image analysis. After mechanical damage, CD44 expression increas
ed up to 500 mu m from the wound edge and for up to 48 h in two human bronc
hial epithelium-derived cell lines, 16HBE14o- and NCI-H292. CD44 expression
was unchanged by interferon-gamma and increased by <50% by tumor necrosis
factor-alpha. To exclude other soluble factors, a Vaseline spacer was used
to temporarily divide petri dishes, with cells at high density on one side
and those at low density on the other. After the spacer was removed, the ce
lls at low cell density growing in the shared medium expressed up to fourfo
ld higher CD44, although cell proliferation was unchanged. Thus increased C
D44 expression at low cell density was not mediated by soluble factors and
may reflect functional involvement in cell motility, dedifferentiation, or
altered cell-substrate adhesion in epithelial repair.