TY - JOUR
T1 - A physical mechanism for coupling bone resorption and formation in adult human bone
AU - Andersen, Thomas Levin
AU - Sondergaard, Teis Esben
AU - Skorzynska, Katarzyna Ewa
AU - Dagnaes-Hansen, Frederik
AU - Plesner, Trine Lindhardt
AU - Hauge, Ellen Margrethe
AU - Plesner, Torben
AU - Delaisse, Jean Marie
PY - 2009/1/1
Y1 - 2009/1/1
N2 - During skeletal remodeling, pre-osteoclasts and preosteoblasts are targeted to critical sites of the bone to resorb and reconstruct bone matrix, respectively. Coordination of site-specific recruitment of these two cell types is a prerequisite to maintain the specific architecture of each bone within strict limits throughout adult life. Here, we determined that the bone marrow microanatomy adjacent to remodeling areas is a central player in this process. By using histomorphometry and multiple immunostainings, we demonstrated in biopsies exhibiting coupled bone resorption and formation that osteoclasts and osteoblasts on the bone surface were always covered by a canopy of flat cells expressing osteoblast markers. In contrast, in biopsies in which this canopy was disrupted, bone formation was deficient. Three-dimensional visualizations revealed that this canopy covered the entire remodeling site and was associated with capillaries, thereby forming a previously unrecognized microanatomical entity. Furthermore, pre-osteoclasts were positioned along these capillaries. These findings led to a model that implicates vasculature in the site-specific recruitment of osteoclasts and osteoblasts and embraces the current knowledge on the molecular mechanism of bone remodeling.
AB - During skeletal remodeling, pre-osteoclasts and preosteoblasts are targeted to critical sites of the bone to resorb and reconstruct bone matrix, respectively. Coordination of site-specific recruitment of these two cell types is a prerequisite to maintain the specific architecture of each bone within strict limits throughout adult life. Here, we determined that the bone marrow microanatomy adjacent to remodeling areas is a central player in this process. By using histomorphometry and multiple immunostainings, we demonstrated in biopsies exhibiting coupled bone resorption and formation that osteoclasts and osteoblasts on the bone surface were always covered by a canopy of flat cells expressing osteoblast markers. In contrast, in biopsies in which this canopy was disrupted, bone formation was deficient. Three-dimensional visualizations revealed that this canopy covered the entire remodeling site and was associated with capillaries, thereby forming a previously unrecognized microanatomical entity. Furthermore, pre-osteoclasts were positioned along these capillaries. These findings led to a model that implicates vasculature in the site-specific recruitment of osteoclasts and osteoblasts and embraces the current knowledge on the molecular mechanism of bone remodeling.
UR - http://www.scopus.com/inward/record.url?scp=58249109354&partnerID=8YFLogxK
U2 - 10.2353/ajpath.2009.080627
DO - 10.2353/ajpath.2009.080627
M3 - Journal article
C2 - 19095960
AN - SCOPUS:58249109354
SN - 0002-9440
VL - 174
SP - 239
EP - 247
JO - American Journal of Pathology
JF - American Journal of Pathology
IS - 1
ER -