Growth factors alter neonatal type II alveolar epithelial cell proliferation.
The type II alveolar epithelial cell plays a critical role in the repair of lung injury by repopulating the entire damaged alveolar epithelium. We report our studies of the effects of known growth factors on the in vitro proliferation of isolated neonatal rabbit type II cells. Transforming growth factor-alpha (TGF-alpha) and epidermal growth factor (EGF) increased [3H]thymidine incorporation, cell number, and labeling index above control. Transforming growth factor-beta (TGF-beta) decreased [3H]thymidine incorporation, cell number, and labeling index compared with control. When added simultaneously, TGF-beta blocked the stimulatory effect of TGF-alpha or EGF. If TGF-alpha is added before TGF-beta, the ability of TGF-beta to block the mitogenic effect of TGF-alpha was diminished the later in time TGF-beta was added. If TGF-beta was added first, later addition of TGF-alpha had no effect. The current work demonstrates that specific growth factors, including some known to be produced by other lung cells, alter the proliferation in vitro of isolated neonatal rabbit type II alveolar epithelial cells.
Ryan
R M
RM
Strong Children's Research Center, Department of Pediatrics (Neonatology), University of Rochester School of Medicine and Dentistry, New York 14642.
Mineo-Kuhn
M M
MM
Kramer
C M
CM
Finkelstein
J N
JN
D000818:Animals; D000831:Animals, Newborn; D002452:Cell Count / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D004815:Epidermal Growth Factor / Q000494:pharmacology*; D004847:Epithelial Cells; D004848:Epithelium / Q000378:metabolism; D011650:Pulmonary Alveoli / Q000166:cytology* / Q000378:metabolism; D011817:Rabbits; D013936:Thymidine / Q000378:metabolism; D016211:Transforming Growth Factor alpha / Q000494:pharmacology*; D016212:Transforming Growth Factor beta / Q000494:pharmacology*
D016211:Transforming Growth Factor alpha; D016212:Transforming Growth Factor beta; D004815:Epidermal Growth Factor; D013936:Thymidine