Β-Tricalcium Phosphate Micron Particles Enhance Calcification of Human Mesenchymal Stem Cells In Vitro. (15th July 2013) - Nakagawa, Yusuke
Abstract : β -Tricalcium phosphate ( β -TCP) micron particles whose diameters range from 1 μ m to 10 μ m have been recently developed, however, their biological effects remain unknown. We investigated the biological effects of β -TCP micron particles on proliferation, cytotoxicity, and calcification of human synovial mesenchymal stem cells (MSCs). MSCs were cultured without dexamethasone, β -glycerophosphate, or ascorbic acid. 1.0 mg/mL β -TCP micron particles inhibited proliferation of MSCs significantly and increased dead cells. In the contact condition, 0.1 mg/mL β -TCP micron particles promoted calcification of MSCs evaluated by alizarin red staining and enhanced mRNA expressions of runx2, osteopontin, and type I collagen. In the noncontact condition, these effects were not observed. 0.1 mg/mL β -TCP micron particles increased calcium concentration in the medium in the contact condition, while 1.0 mg/mL β -TCP micron particles decreased calcium and phosphorus concentrations in the medium in the noncontact condition. By transmission electron microscopy, β -TCP micron particles were localized in the phagosome of MSCs and were dissolved. In conclusion, β -TCP micron particles promoted calcification of MSCs and enhanced osteogenesis-related gene expressions in vitro .