Transforming growth factors-beta 1 and beta 2 are mitogens for rat Schwann cells.
Transforming growth factor-beta 1 (TGF-beta 1) and TGF-beta 2 were found to be potent mitogens for purified rat Schwann cells, each stimulating DNA synthesis in quiescent cells and also increasing their proliferation rate. Half-maximal stimulation of DNA synthesis occurred at approximately 0.1 ng/ml TGF-beta 1 or TGF-beta 2. Mitogenic stimulation by TGF-beta 1 and TGF-beta 2 was enhanced by forskolin, which activates adenylate cyclase, at concentrations up to 0.5 microM forskolin. However, at 5 microM forskolin, the synergistic interaction between forskolin and TGF-beta 1 was abolished. These results are in contrast to the observed synergy between forskolin and another Schwann cell mitogen, glial growth factor (GGF). Both 0.5 and 5 microM forskolin were found to enhance the stimulation of DNA synthesis by partially purified GGF (GGF-CM). As well as being functionally distinct, TGF-beta 1 and GGF-CM activities were also physically separable by chromatography on a Superose 12 gel permeation column. Thus, TGF-beta 1 and beta 2 are rat Schwann cell mitogens, and Schwann cells are one of the few normal cell populations to respond mitogenically to TGF-beta.
Ridley
A J
AJ
Imperial Cancer Research Fund, London, United Kingdom.
Davis
J B
JB
Stroobant
P
P
Land
H
H
D000818:Animals; D002455:Cell Division; D002850:Chromatography, Gel; D005576:Colforsin / Q000494:pharmacology; D000242:Cyclic AMP / Q000378:metabolism; D004247:DNA / Q000096:biosynthesis*; D004357:Drug Synergism; D020904:Glia Maturation Factor; D008934:Mitogens; D009419:Nerve Tissue Proteins / Q000502:physiology; D009423:Nervous System Neoplasms / Q000209:etiology; D051381:Rats; D011919:Rats, Inbred Strains; D012583:Schwann Cells / Q000166:cytology*; D012584:Sciatic Nerve / Q000166:cytology*; D015291:Transforming Growth Factors / Q000494:pharmacology / Q000502:physiology*
D020904:Glia Maturation Factor; D008934:Mitogens; D009419:Nerve Tissue Proteins; D005576:Colforsin; D015291:Transforming Growth Factors; D004247:DNA; D000242:Cyclic AMP