Dataset Information

Vascularization of primary and secondary ossification centres in the human growth plate.

ABSTRACT:

Background

The switch from cartilage template to bone during endochondral ossification of the growth plate requires a dynamic and close interaction between cartilage and the developing vasculature. Vascular invasion of the primarily avascular hypertrophic chondrocyte zone brings chondroclasts, osteoblast- and endothelial precursor cells into future centres of ossification.Vascularization of human growth plates of polydactylic digits was studied by immunohistochemistry, confocal-laser-scanning-microscopy and RT-qPCR using markers specific for endothelial cells CD34 and CD31, smooth muscle cells ?-SMA, endothelial progenitor cells CD133, CXCR4, VEGFR-2 and mesenchymal progenitor cells CD90 and CD105. In addition, morphometric analysis was performed to quantify RUNX2+ and DLX5+ hypertrophic chondrocytes, RANK+ chondro- and osteoclasts, and CD133+ progenitors in different zones of the growth plate.

Results

New vessels in ossification centres were formed by sprouting of CD34+ endothelial cells that did not co-express the mature endothelial cell marker CD31. These immature vessels in the growth plate showed no abluminal coverage with ?-SMA+ smooth muscle cells, but in their close proximity single CD133+ precursor cells were found that did not express VEGFR-2, a marker for endothelial lineage commitment. In periosteum and in the perichondrial groove of Ranvier that harboured CD90+/CD105+ chondro-progenitors, in contrast, mature vessels were found stabilized by ?-SMA+ smooth muscle cells.

Conclusion

Vascularization of ossification centres of the growth plate was mediated by sprouting of capillaries coming from the bone collar or by intussusception rather than by de-novo vessel formation involving endothelial progenitor cells. Vascular invasion of the joint anlage was temporally delayed compared to the surrounding joint tissue.

SUBMITTER: Walzer SM

PROVIDER: S-EPMC4236517 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature

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Publications

Vascularization of primary and secondary ossification centres in the human growth plate.

Walzer Sonja M SM Cetin Erdal E Grübl-Barabas Ruth R Sulzbacher Irene I Rueger Beate B Girsch Werner W Toegel Stefan S Windhager Reinhard R Fischer Michael B MB

BMC developmental biology 20140828

<h4>Background</h4>The switch from cartilage template to bone during endochondral ossification of the growth plate requires a dynamic and close interaction between cartilage and the developing vasculature. Vascular invasion of the primarily avascular hypertrophic chondrocyte zone brings chondroclasts, osteoblast- and endothelial precursor cells into future centres of ossification.Vascularization of human growth plates of polydactylic digits was studied by immunohistochemistry, confocal-laser-sca ...[more]

PMID: 25164565

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Dataset Information

Vascularization of primary and secondary ossification centres in the human growth plate.

Background

Results

Conclusion

Publications

Vascularization of primary and secondary ossification centres in the human growth plate.

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