Activation of the bone-derived latent TGF beta complex by isolated osteoclasts.
Although TGF beta is unquestionably an important growth regulatory polypeptide with effects on many cell types, the cellular mechanisms which release it from the binding proteins which mask its biological activity are not well understood. Here we show that when isolated osteoclasts are activated, they release active TGF beta from the latent TGF beta complex produced by bone organ cultures. Since active TGF beta has powerful inhibitory effects on osteoclast formation and bone resorption and stimulates osteoblast activity, is present in abundant amounts in the bone matrix and is released during hormone-stimulated osteoclastic bone resorption, the activation of TGF beta by stimulated osteoclasts may be an important regulatory step in normal bone remodeling.
Oreffo
R O
RO
Department of Medicine/Endocrinology, University of Texas Health Science Center, San Antonio 78284-7877.
Mundy
G R
GR
Seyedin
S M
SM
Bonewald
L F
LF
D000818:Animals; D001854:Bone Marrow Cells; D001842:Bone and Bones / Q000378:metabolism*; D002460:Cell Line; D003470:Culture Media; D006863:Hydrogen-Ion Concentration; D051379:Mice; D009924:Organ Culture Techniques; D010010:Osteoclasts / Q000187:drug effects / Q000502:physiology*; D015291:Transforming Growth Factors / Q000378:metabolism*; D014801:Vitamin A / Q000494:pharmacology
D003470:Culture Media; D014801:Vitamin A; D015291:Transforming Growth Factors