Comparison of human alveolar osteoblasts cultured on polymer-ceramic composite scaffolds and tissue culture plates.
The effects of medical grade polycaprolactone-tricalcium phosphate (mPCL-TCP) (80:20) scaffolds on primary human alveolar osteoblasts (AOs) were compared with standard tissue-culture plates. Of the seeded AOs, 70% adhered to and proliferated on the scaffold surface and within open and interconnected pores; they formed multi-layered sheets and collagen fibers with uniform distribution within 28 days. Elevation of alkaline phosphatase activity occurred in scaffold-cell constructs independent of osteogenic induction. AO proliferation rate increased and significant decrease in calcium concentration of the medium for both scaffolds and plates under induction conditions were seen. mPCL-TCP scaffolds significantly influenced the AO expression pattern of osterix and osteocalcin (OCN). Osteogenic induction down-regulated OCN at both RNA and protein level on scaffolds (3D) by day 7, and up-regulated OCN in cell-culture plates (2D) by day 14, but OCN levels on scaffolds were higher than on cell-culture plates. Immunocytochemical signals for type I collagen, osteopontin and osteocalcin were detected at the outer parts of scaffold-cell constructs. More mineral nodules were found in induced than in non-induced constructs. Only induced 2D cultures showed nodule formation. mPCL-TCP scaffolds appear to stimulate osteogenesis in vitro by activating a cellular response in AO's to form mineralized tissue. There is a fundamental difference between culturing AOs on 2D and 3D environments that should be considered when studying osteogenesis in vitro.
Yefang
Z
Z
Department of Biological Sciences, National University of Singapore, Singapore 119260, Singapore.
Hutmacher
D W
DW
Varawan
S-L
SL
Meng
L T
LT
D000469:Alkaline Phosphatase / Q000096:biosynthesis; D000539:Alveolar Process / Q000166:cytology; D000704:Analysis of Variance; D002130:Calcium Phosphates; D018929:Cell Culture Techniques; D049109:Cell Proliferation; D002478:Cells, Cultured; D002516:Ceramics; D024042:Collagen Type I / Q000096:biosynthesis; D004337:Drug Carriers; D005898:Glass; D006801:Humans; D010006:Osteoblasts / Q000166:cytology / Q000378:metabolism; D015675:Osteocalcin / Q000096:biosynthesis; D010012:Osteogenesis; D053495:Osteopontin / Q000096:biosynthesis; D011091:Polyesters; D016062:Porosity; D023822:Tissue Engineering / Q000379:methods*
D002130:Calcium Phosphates; D024042:Collagen Type I; D004337:Drug Carriers; D011091:Polyesters; D015675:Osteocalcin; D053495:Osteopontin; C016240:polycaprolactone; D000469:Alkaline Phosphatase; C018392:tricalcium phosphate