The Crosstalk between Osteoclasts and Osteoblasts Is Dependent upon the Composition and Structure of Biphasic Calcium Phosphates

• Published in: PloS one 2015-07, Vol.10 (7), p.e0132903-e0132903
• Main Authors: Shiwaku, Yukari, Neff, Lynn, Nagano, Kenichi, Takeyama, Ken-Ichi, de Bruijn, Joost, Dard, Michel, Gori, Francesca, Baron, Roland
• Format: Article
• Language: English
• Subjects: Acid phosphatase (tartrate-resistant); Animals; Biocompatibility; Biological products; Biology; Biomaterials; Biomedical materials; Bone composition; Bone growth; Bone resorption; Bone surgery; Calcium; Calcium phosphate; Calcium phosphates; Cell Communication; Cell Differentiation; Cells, Cultured; Chemical composition; Chemistry; Collagen; Coupling; Coupling factors; Crosstalk; Defects; Dentistry; Differentiation; Extracellular Matrix Proteins - metabolism; Female; Gene expression; Hydroxyapatite; Hydroxyapatites; Hydroxyapatites - chemistry; Infections; Kinases; Male; Medicine; Mice; Mice, Inbred C57BL; Microscopy, Confocal; Osteoblastogenesis; Osteoblasts; Osteoblasts - cytology; Osteoblasts - metabolism; Osteoclastogenesis; Osteoclasts; Osteoclasts - cytology; Osteoclasts - metabolism; Osteoconduction; Osteogenesis; Phosphates; Phosphotransferases (Alcohol Group Acceptor) - metabolism; Scaffolds; Sphingosine; Surgical implants; TCP/IP (Network protocols); Topography; Tricalcium phosphate
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0132903

Biphasic calcium phosphates (BCPs), consisting of hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP), exhibit good biocompatibility and osteoconductivity, maintaining a balance between resorption of the biomaterial and formation of new bone. We tested whether the chemical composition and/or the microstructure of BCPs affect osteoclasts (OCs) differentiation and/or their ability to crosstalk with osteoblasts (OBs). To this aim, OCs were cultured on BCPs with HA content of 5, 20 or 60% and their differentiation and activity were assessed. We found that OC differentiation is partially impaired by increased HA content, but not by the presence of micropores within BCP scaffolds, as indicated by TRAP staining and gene profile expression. We then investigated whether the biomaterial-induced changes in OC differentiation also affect their ability to crosstalk with OBs and regulate OB function. We found that BCPs with low percentage of HA favored the expression of positive coupling factors, including sphingosine-kinase 1 (SPHK1) and collagen triple helix repeat containing 1 (Cthrc1). In turn, the increase of these secreted coupling factors promotes OB differentiation and function. All together our studies suggest that the chemical composition of biomaterials affects not only the differentiation and activity of OCs but also their potential to locally regulate bone formation.