N Takahashi, B R MacDonald, J Hon, M E Winkler, R Derynck, G R Mundy, G D Roodman
J Clin Invest.
1986;
78(4):894–898
doi:10.1172/JCI112677
This article Copyright © 1986, The American Society for Clinical Investigation
Abstract
|
Full text
|
PDF
T
ransforming growth factor-alpha (TGF-alpha) is synthesized by a variety of tumor cell lines and stimulates osteoclastic bone resorption in vitro. The mechanism by which TGF-alpha increases osteoclast activity is unknown. We used a human marrow culture system that forms osteoclast-like multinucleated cells (MNCs) to determine the effects of recombinant human TGF-alpha on MNC formation. Addition of 0.01 ng/ml TGF-alpha for the 1st week followed by 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] for the subsequent 2 wk significantly increased MNCs. Treatment of these cultures with TGF-alpha without later addition of 1,25(OH)2D3 did not increase MNC formation. Autoradiographic studies revealed that TGF-alpha stimulated proliferation of precursors for MNCs, and 1,25(OH)2D3 increased their rate of fusion into MNCs. Addition of murine epidermal growth factor (EGF) (0.1 ng/ml) followed by 1,25(OH)2D3 also significantly stimulated MNC formation. These data suggest that TGF-alpha and EGF may stimulate bone resorption by increasing the proliferation of osteoclast precursors, which leads to increased numbers of osteoclasts.
This file is in Adobe Acrobat (PDF) format.
If you have not installed and configured the Adobe Acrobat Reader on your system.
Having trouble reading a PDF?
PDFs are designed to be printed out and read, but if you prefer to read them online, you may find it easier if you increase the view size to 125%.
Having trouble saving a PDF?
Many versions of the free Acrobat Reader do not
allow Save. You must instead save the PDF from the JCI Online page you downloaded it from. PC users:
Right-click on the Download link and choose the option that says something like "Save Link As...".
Mac users should hold the mouse button down on the link to get these same options.
Having trouble printing a PDF?
- Try printing one page at a time or to a newer printer.
- Try saving the file to disk before printing rather than opening it "on the fly." This requires that you
configure your browser to "Save" rather than "Launch Application" for the file type "application/pdf", and can
usually be done in the "Helper Applications" options.
- Make sure you are using the latest version of Adobe's Acrobat Reader.
