TY - JOUR
T1 - Elevated extracellular calcium stimulates secretion of bone morphogenetic protein 2 by a macrophage cell line
AU - Honda, Yoshitomo
AU - Anada, Takahisa
AU - Kamakura, Shinji
AU - Nakamura, Masanori
AU - Sugawara, Shunji
AU - Suzuki, Osamu
N1 - Funding Information:
We thank Dr. T. Kuroishi, Department of Oral Immunology, Graduate School of Dentistry, for his valuable criticism during the preparation of the manuscript. This study was supported by Grants-in Aid (17076001) from Ministry of Education, Science, Sports and Culture of Japan.
PY - 2006/7/7
Y1 - 2006/7/7
N2 - It has been suggested that macrophages and multinucleated giant cells are responsible for phagocytosis of resorbable calcium phosphate (CaP) compounds implanted in bone defects. However, function of macrophages around the CaP, if continuously exposed to various concentration of extracellular calcium ions ([Ca2+]o), is still unknown. The present study showed that when resorbable octacalcium phosphate was implanted in mouse calvaria, macrophage-like cells were observed around the implant during bone formation. Then, experiments were designed to investigate whether secretion of bone morphogenetic protein 2 (BMP-2) is enhanced by [Ca2+]o in a macrophage cell line (J774A.1) in vitro. The mRNA expression and the secretion of BMP-2 in J774A.1 cells were significantly increased when incubated in the medium with [Ca2+]o up to 14 mM. The promotion of mRNA expression was maintained even when incubated with a small amount of minute CaP crystals. The present results suggest that [Ca2+]o above physiological concentration may stimulate macrophages to induce osteogenic cytokine, such as BMP-2, for bone formation by osteoblast.
AB - It has been suggested that macrophages and multinucleated giant cells are responsible for phagocytosis of resorbable calcium phosphate (CaP) compounds implanted in bone defects. However, function of macrophages around the CaP, if continuously exposed to various concentration of extracellular calcium ions ([Ca2+]o), is still unknown. The present study showed that when resorbable octacalcium phosphate was implanted in mouse calvaria, macrophage-like cells were observed around the implant during bone formation. Then, experiments were designed to investigate whether secretion of bone morphogenetic protein 2 (BMP-2) is enhanced by [Ca2+]o in a macrophage cell line (J774A.1) in vitro. The mRNA expression and the secretion of BMP-2 in J774A.1 cells were significantly increased when incubated in the medium with [Ca2+]o up to 14 mM. The promotion of mRNA expression was maintained even when incubated with a small amount of minute CaP crystals. The present results suggest that [Ca2+]o above physiological concentration may stimulate macrophages to induce osteogenic cytokine, such as BMP-2, for bone formation by osteoblast.
KW - BMP-2
KW - Biomaterial
KW - Bone
KW - Calcium
KW - Macrophage
KW - Octacalcium phosphate
KW - Resorbable calcium phosphate
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U2 - 10.1016/j.bbrc.2006.05.013
DO - 10.1016/j.bbrc.2006.05.013
M3 - Article
C2 - 16716259
AN - SCOPUS:33646846609
VL - 345
SP - 1155
EP - 1160
JO - Biochemical and Biophysical Research Communications
JF - Biochemical and Biophysical Research Communications
SN - 0006-291X
IS - 3
ER -