Limits...
Matrix metalloproteinase 9 and vascular endothelial growth factor are essential for osteoclast recruitment into developing long bones.

Engsig MT, Chen QJ, Vu TH, Pedersen AC, Therkidsen B, Lund LR, Henriksen K, Lenhard T, Foged NT, Werb Z, Delaissé JM - J. Cell Biol. (2000)

Bottom Line: Hanahan. 2000.Cell Biol. 2:737-744).These observations identify specific actions of MMP-9 and VEGF that are critical for early bone development.

View Article: PubMed Central - PubMed

Affiliation: OSTEOPRO A/S and Center for Clinical and Basic Research, DK-2750 Herlev/Ballerup, Denmark. me@osteopro.dk

ABSTRACT
Bone development requires the recruitment of osteoclast precursors from surrounding mesenchyme, thereby allowing the key events of bone growth such as marrow cavity formation, capillary invasion, and matrix remodeling. We demonstrate that mice deficient in gelatinase B/matrix metalloproteinase (MMP)-9 exhibit a delay in osteoclast recruitment. Histological analysis and specialized invasion and bone resorption models show that MMP-9 is specifically required for the invasion of osteoclasts and endothelial cells into the discontinuously mineralized hypertrophic cartilage that fills the core of the diaphysis. However, MMPs other than MMP-9 are required for the passage of the cells through unmineralized type I collagen of the nascent bone collar, and play a role in resorption of mineralized matrix. MMP-9 stimulates the solubilization of unmineralized cartilage by MMP-13, a collagenase highly expressed in hypertrophic cartilage before osteoclast invasion. Hypertrophic cartilage also expresses vascular endothelial growth factor (VEGF), which binds to extracellular matrix and is made bioavailable by MMP-9 (Bergers, G., R. Brekken, G. McMahon, T.H. Vu, T. Itoh, K. Tamaki, K. Tanzawa, P. Thorpe, S. Itohara, Z. Werb, and D. Hanahan. 2000. Nat. Cell Biol. 2:737-744). We show that VEGF is a chemoattractant for osteoclasts. Moreover, invasion of osteoclasts into the hypertrophic cartilage requires VEGF because it is inhibited by blocking VEGF function. These observations identify specific actions of MMP-9 and VEGF that are critical for early bone development.

Show MeSH

Related in: MedlinePlus

Effect of VEGF on osteoclast migration. Osteoclasts were cultured overnight on collagen-coated membranes of culture inserts (average of 1,032 osteoclasts/insert). These inserts were placed in 12-well plates containing the indicated concentration of VEGF. 100 ng/ml Flt-1/Fc was added to the culture inserts where indicated. The migrations were scored as explained in Materials and Methods, and are shown as mean ± SD of four cultures. *Significant effect compared with osteoclasts cultured without additive (P < 0.05).
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC2169432&req=5

Figure 10: Effect of VEGF on osteoclast migration. Osteoclasts were cultured overnight on collagen-coated membranes of culture inserts (average of 1,032 osteoclasts/insert). These inserts were placed in 12-well plates containing the indicated concentration of VEGF. 100 ng/ml Flt-1/Fc was added to the culture inserts where indicated. The migrations were scored as explained in Materials and Methods, and are shown as mean ± SD of four cultures. *Significant effect compared with osteoclasts cultured without additive (P < 0.05).

Mentions: To further explore whether VEGF acts directly on osteoclasts and exerts chemotactic activity, we seeded osteoclasts differentiated from bone marrow precursors in vitro in the upper chamber of culture inserts with collagen-coated membranes, and determined their migration to the lower surface of the membranes in the presence of increasing concentrations of VEGF in the lower chamber. VEGF stimulated migration of the cells (Fig. 10). This effect of VEGF was abolished by addition of hFlt-Fc to the upper chamber. These observations show that VEGF can act directly on osteoclasts and is chemotactic for them.


Matrix metalloproteinase 9 and vascular endothelial growth factor are essential for osteoclast recruitment into developing long bones.

Engsig MT, Chen QJ, Vu TH, Pedersen AC, Therkidsen B, Lund LR, Henriksen K, Lenhard T, Foged NT, Werb Z, Delaissé JM - J. Cell Biol. (2000)

Effect of VEGF on osteoclast migration. Osteoclasts were cultured overnight on collagen-coated membranes of culture inserts (average of 1,032 osteoclasts/insert). These inserts were placed in 12-well plates containing the indicated concentration of VEGF. 100 ng/ml Flt-1/Fc was added to the culture inserts where indicated. The migrations were scored as explained in Materials and Methods, and are shown as mean ± SD of four cultures. *Significant effect compared with osteoclasts cultured without additive (P < 0.05).
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2169432&req=5

Figure 10: Effect of VEGF on osteoclast migration. Osteoclasts were cultured overnight on collagen-coated membranes of culture inserts (average of 1,032 osteoclasts/insert). These inserts were placed in 12-well plates containing the indicated concentration of VEGF. 100 ng/ml Flt-1/Fc was added to the culture inserts where indicated. The migrations were scored as explained in Materials and Methods, and are shown as mean ± SD of four cultures. *Significant effect compared with osteoclasts cultured without additive (P < 0.05).
Mentions: To further explore whether VEGF acts directly on osteoclasts and exerts chemotactic activity, we seeded osteoclasts differentiated from bone marrow precursors in vitro in the upper chamber of culture inserts with collagen-coated membranes, and determined their migration to the lower surface of the membranes in the presence of increasing concentrations of VEGF in the lower chamber. VEGF stimulated migration of the cells (Fig. 10). This effect of VEGF was abolished by addition of hFlt-Fc to the upper chamber. These observations show that VEGF can act directly on osteoclasts and is chemotactic for them.

Bottom Line: Hanahan. 2000.Cell Biol. 2:737-744).These observations identify specific actions of MMP-9 and VEGF that are critical for early bone development.

View Article: PubMed Central - PubMed

Affiliation: OSTEOPRO A/S and Center for Clinical and Basic Research, DK-2750 Herlev/Ballerup, Denmark. me@osteopro.dk

ABSTRACT
Bone development requires the recruitment of osteoclast precursors from surrounding mesenchyme, thereby allowing the key events of bone growth such as marrow cavity formation, capillary invasion, and matrix remodeling. We demonstrate that mice deficient in gelatinase B/matrix metalloproteinase (MMP)-9 exhibit a delay in osteoclast recruitment. Histological analysis and specialized invasion and bone resorption models show that MMP-9 is specifically required for the invasion of osteoclasts and endothelial cells into the discontinuously mineralized hypertrophic cartilage that fills the core of the diaphysis. However, MMPs other than MMP-9 are required for the passage of the cells through unmineralized type I collagen of the nascent bone collar, and play a role in resorption of mineralized matrix. MMP-9 stimulates the solubilization of unmineralized cartilage by MMP-13, a collagenase highly expressed in hypertrophic cartilage before osteoclast invasion. Hypertrophic cartilage also expresses vascular endothelial growth factor (VEGF), which binds to extracellular matrix and is made bioavailable by MMP-9 (Bergers, G., R. Brekken, G. McMahon, T.H. Vu, T. Itoh, K. Tamaki, K. Tanzawa, P. Thorpe, S. Itohara, Z. Werb, and D. Hanahan. 2000. Nat. Cell Biol. 2:737-744). We show that VEGF is a chemoattractant for osteoclasts. Moreover, invasion of osteoclasts into the hypertrophic cartilage requires VEGF because it is inhibited by blocking VEGF function. These observations identify specific actions of MMP-9 and VEGF that are critical for early bone development.

Show MeSH
Related in: MedlinePlus