Crosstalk of osteoblast and osteoclast precursors on mineralized collagen-towards an in vitro model for bone remodeling

• Published in: Journal of biomedical materials research. Part A 2010-12, Vol.95A (3), p.848-856
• Main Authors: Bernhardt, A., Thieme, S., Domaschke, H., Springer, A., Rösen-Wolff, A., Gelinsky, M.
• Format: Article
• Language: English
• Subjects: Acid Phosphatase - metabolism; Alkaline Phosphatase - genetics; Alkaline Phosphatase - metabolism; Biocompatibility; Biocompatible Materials - chemistry; Biocompatible Materials - metabolism; Biological and medical sciences; Biomedical materials; bone remodeling; Bone Remodeling - physiology; Bones; Cell Culture Techniques; Cell Differentiation - physiology; Cell Proliferation; Cells, Cultured; coculture; Coculture Techniques; Collagen - chemistry; Collagen - metabolism; Differentiation; Extracellular Matrix - chemistry; Extracellular Matrix - metabolism; Fundamental and applied biological sciences. Psychology; Gene expression; Humans; In vitro testing; Isoenzymes - metabolism; Materials Testing; Medical sciences; Mesenchymal Stromal Cells - cytology; Mesenchymal Stromal Cells - physiology; monocytes; Monocytes - cytology; Monocytes - physiology; MSC; Nanocomposites - chemistry; osteoblast; Osteoblasts - cytology; Osteoblasts - physiology; osteoclast; Osteoclasts - cytology; Osteoclasts - physiology; Scanning electron microscopy; Skeleton and joints; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Surgical implants; Tartrate-Resistant Acid Phosphatase; Technology. Biomaterials. Equipments; Vertebrates: osteoarticular system, musculoskeletal system
• ISSN: 1549-3296; 1552-4965; 1552-4965
• DOI: 10.1002/jbm.a.32856

Bone remodeling and, therefore, integration of implant materials require the coordinated regulation of osteoblast and osteoclast activity. This is why the in vitro evaluation of biomaterials for bone regeneration should involve not only the analysis of osteoblast differentiation but also the formation and differentiation of osteoclasts. In the present study, we applied a material made of mineralized collagen I that mimics extracellular bone matrix to establish a culture system, which allows the cocultivation of human monocytes and human mesenchymal stem cells (hMSCs), which were differentiated into osteoclast‐like cells and osteoblasts, respectively. Both cell types were cultivated on membrane‐like structures from mineralized collagen. Transwell inserts were used to spatially separate the cell types but allowed exchange of soluble factors. The osteoclastogenesis and osteogenic differentiation were evaluated by analysis of gene expression, determination of alkaline phosphatase (ALP), and tartrate‐resistant acidic phosphatase (TRAP) activity. Furthermore, cell morphology was studied using scanning electron and transmission electron microscopy. Osteogenically induced hMSC showed an increased specific ALP activity as well as increased gene expression of gene coding for alkaline phosphatase (ALPL), when cocultivated with differentiating osteoclasts. Adipogenic differentiation of hMSCs was suppressed by the presence of osteoclasts as indicated by a major decrease in adipocyte cell number and a decrease in gene expression of adipogenic markers. The formation of multinucleated osteoclasts seems to be decreased in the presence of osteogenically induced hMSC as indicated by electron microscopic evaluation and determination of TRAP activity. However, gene expression of osteoclast markers was not decreased in coculture with osteogenically induced hMSC. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2010.