Nanomechanical properties of individual chondrocytes and their developing growth factor-stimulated pericellular matrix.
J Biomech
; 40(5): 1011-23, 2007.
Article
em En
| MEDLINE
| ID: mdl-16793050
ABSTRACT
The nanomechanical properties of individual cartilage cells (chondrocytes) and their aggrecan and collagen-rich pericellular matrix (PCM) were measured via atomic force microscope nanoindentation using probe tips of two length scales (nanosized and micron-sized). The properties of cells freshly isolated from cartilage tissue (devoid of PCM) were compared to cells that were cultured for selected times (up to 28 days) in 3-D alginate gels which enabled PCM assembly and accumulation. Cells were immobilized and kept viable in pyramidal wells microfabricated into an array on silicon chips. Hertzian contact mechanics and finite element analyses were employed to estimate apparent moduli from the force versus depth curves. The effects of culture conditions on the resulting PCM properties were studied by comparing 10% fetal bovine serum to medium containing a combination of insulin growth factor-1 (IGF-1)+osteogenic protein-1 (OP-1). While both systems showed increases in stiffness with time in culture between days 7 and 28, the IGF-1+OP-1 combination resulted in a higher stiffness for the cell-PCM composite by day 28 and a higher apparent modulus of the PCM which is compared to the FBS cultured cells. These studies give insight into the temporal evolution of the nanomechanical properties of the pericellar matrix relevant to the biomechanics and mechanobiology of tissue-engineered constructs for cartilage repair.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Condrócitos
/
Peptídeos e Proteínas de Sinalização Intercelular
/
Matriz Extracelular
Limite:
Animals
Idioma:
En
Revista:
J Biomech
Ano de publicação:
2007
Tipo de documento:
Article
País de afiliação:
Estados Unidos