Js. Hagood et al., Differential expression of platelet-derived growth factor-alpha receptor by Thy-1(-) and Thy-1(+) lung fibroblasts, AM J P-LUNG, 21(1), 1999, pp. L218-L224
Citations number
29
Categorie Soggetti
da verificare
Journal title
AMERICAN JOURNAL OF PHYSIOLOGY-LUNG CELLULAR AND MOLECULAR PHYSIOLOGY
Fibroblasts are heterogeneous with respect to surface markers, morphology,
and participation in fibrotic responses. This study was undertaken to deter
mine whether Thy-1(-) and Thy-1(+) rat lung fibroblasts, which have distinc
t and relevant phenotypes, differ in their proliferative responses to plate
let-derived growth factor (PDGF) isoforms. Homogeneous populations of Thy-1
(-) and Thy-1(+) fibroblasts were found to proliferate equally in the prese
nce of PDGF-BB, but PDGF-AA-mediated proliferation occurred only in Thy-1(-
) cells. This differential activity correlated with significantly higher ex
pression of PDGF-alpha receptor in Thy-1(+) fibroblasts as shown by immunob
lotting, immunofluorescence, and Northern blotting. There was a rapid incre
ase in c-myc mRNA in Thy-1(-) but not in Thy-1(+) fibroblasts on stimulatio
n with PDGF-AA and PDGF-BB. The PDGF-alpha receptor, which mediates signali
ng by all PDGF isoforms, has been implicated in numerous clinical and exper
imental forms of fibrosis and regulates lung morphogenesis. Differential ex
pression of the PDGF-alpha receptor supports distinct roles for Thy-1(-) an
d Thy-1(+) fibroblast populations in developmental and fibrotic processes i
n the lung.