Bone tissue engineering by primary osteoblast-like cells in a monolayer system and 3-dimensional collagen gel.
OBJECTIVE
To engineer living bone tissue in vitro, bone cells must be multiplied and differentiated in cell culture. Osteoblasts are known to be the crucial cells responsible for the bone modeling process. Periosteal-derived osteoblasts were therefore cultured for up to 3 weeks in Petri dishes as well as in a 3-dimensional collagen gel.


METHODS
Proliferation, migration, and differentiation of cells as well as the synthesis of extracellular matrix proteins were monitored during the culture period by histology, electron microscopy, and immunohistochemistry. Mineral formation was investigated by electron diffraction studies and element analysis.


RESULTS
Osteoblasts proliferated and migrated in Petri dishes as well as in the collagen gel without loss of viability during the whole experimental period. They demonstrated a mature osteoblast phenotype as indicated by the synthesis of a bone-like extracellular matrix. They formed an extracellular matrix containing osteocalcin, osteonectin, and newly synthesized collagen type I in both environments. Mineral formation was seen in colocalization with the bone-like extracellular matrix proteins in Petri dishes. Microanalytical investigations revealed a matrix vesicle-mediated mineral formation at early stages of culture.


CONCLUSIONS
Our cell culture confirmed the ability to multiplicate differentiated and viable osteoblast-like cells in 2- and 3-dimensional space. Additionally, bone-like mineralization can be induced by primary osteoblasts in monolayer culture. The data suggest that this approach can be used as a tool in bone tissue engineering.
Wiesmann
Hans Peter
HP
Klinik and Poliklinik für Mund und Kiefer-Gesichtschirurgie, Universitäatklinikum Münster, Germany. wiesmap@uni-muenster.de
Nazer
Noorul
N
Klatt
Christina
C
Szuwart
Thomas
T
Meyer
Ulrich
U
D000818:Animals; D018786:Bone Substitutes; D002113:Calcification, Physiologic / Q000502:physiology; D002417:Cattle; D018929:Cell Culture Techniques / Q000379:methods; D002454:Cell Differentiation / Q000502:physiology; D002455:Cell Division / Q000502:physiology; D002465:Cell Movement / Q000502:physiology; D002478:Cells, Cultured; D024042:Collagen Type I / Q000378:metabolism*; D016326:Extracellular Matrix Proteins / Q000378:metabolism; D005782:Gels; D010006:Osteoblasts / Q000166:cytology / Q000378:metabolism* / Q000648:ultrastructure; D015675:Osteocalcin / Q000378:metabolism*; D015676:Osteonectin / Q000378:metabolism*; D010521:Periosteum / Q000166:cytology / Q000378:metabolism; D023822:Tissue Engineering / Q000379:methods*
D018786:Bone Substitutes; D024042:Collagen Type I; D016326:Extracellular Matrix Proteins; D005782:Gels; D015676:Osteonectin; D015675:Osteocalcin