Fetal rat lung type II cell differentiation in serum-free isolated cell culture: modulation and inhibition.
Undifferentiated fetal rat lung epithelial cells were isolated on gestational days 15 or 17 (term 22 days) and cultured in a defined medium. On plastic, most of the cells developed structurally abnormal lamellar bodies. On a basement membrane matrix (BMM), they sequentially accumulated glycogen and formed typical lamellar bodies. Biochemical analysis of the latter indicated that they had a phospholipid composition typical of surfactant for cells on BMM but not on plastic and that surfactant protein A appeared on BMM only. Progressing maturation from day 1 to day 6 in culture was demonstrated for 17-day cells on BMM by a sevenfold increase of labeled precursor incorporation into surfactant phospholipids. Exposure to medium conditioned by 21-day fetal fibroblasts enhanced incorporation already after a 1-day culture. The antisteroid RU 486 had no effect on differentiation, whereas transforming growth factor-beta, a factor produced by lung mesenchyme at early fetal stages, inhibited it markedly. Alveolar epithelial type II cells appear to be committed early, but their maturational process would be prevented until a definite gestational stage.
Fraslon
C
C
Centre de Biologie Cellulaire, Centre National de la Recherche Scientifique, Ivry/Seine, France.
Lacaze-Masmonteil
T
T
Zupan
V
V
Chailley-Heu
B
B
Bourbon
J R
JR
D000085:Acetates / Q000378:metabolism; D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects*; D002478:Cells, Cultured; D002794:Choline / Q000378:metabolism; D017077:Culture Media, Conditioned; D016895:Culture Media, Serum-Free; D003907:Dexamethasone / Q000494:pharmacology; D004797:Enzyme-Linked Immunosorbent Assay; D004847:Epithelial Cells; D004848:Epithelium / Q000378:metabolism / Q000648:ultrastructure; D005260:Female; D005333:Fetus; D005865:Gestational Age; D006854:Hydrocortisone / Q000494:pharmacology; D015151:Immunoblotting; D007700:Kinetics; D008055:Lipids / Q000096:biosynthesis; D008168:Lung / Q000166:cytology* / Q000378:metabolism / Q000648:ultrastructure; D008854:Microscopy, Electron; D015735:Mifepristone / Q000494:pharmacology; D010743:Phospholipids / Q000096:biosynthesis / Q000302:isolation & purification / Q000378:metabolism*; D011510:Proteolipids / Q000302:isolation & purification / Q000378:metabolism; D037661:Pulmonary Surfactant-Associated Proteins; D011663:Pulmonary Surfactants / Q000302:isolation & purification / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors; D016212:Transforming Growth Factor beta / Q000494:pharmacology*
D000085:Acetates; D017077:Culture Media, Conditioned; D016895:Culture Media, Serum-Free; D008055:Lipids; D010743:Phospholipids; D011510:Proteolipids; D037661:Pulmonary Surfactant-Associated Proteins; D011663:Pulmonary Surfactants; D016212:Transforming Growth Factor beta; D015735:Mifepristone; D003907:Dexamethasone; D002794:Choline; D006854:Hydrocortisone