by 張志豪, 2011-03-14 13:27, Views(837)

My major research interest is total joint replacement, biomaterials

and tissue engineering.

The lateral view preoperative radiograph shows complete loss of

joint space and severe osteophyte formation on the posterior surfaces

of the femur and the tibia (A). The immediate postoperative view

shows good alignment of the knee and complete removal of all the

osteophytes (B).

We describe a biomimetic mode of insoluble signaling stimulation to

provide target delivery of bone morphogenetic protein-2 (BMP-2),

with the aim of prolonging the retention of BMP-2 use in bone tissue

engineering and to enable its localized release in response to cellular

activity. In our novel localization process,we used heterobifunctional
acrylate-N-hydroxysuccinimide poly(ethylene glycol) (PEG) as a spacer

to tether BMP-2 onto a poly(lactide-co-glycolide) scaffold. Use of

PEG-tethered BMP-2 was feasible because BMP-2 retained its activity

after covalent conjugation. The PEG-tethered BMP-2 conjugate sustained

stimulation and retained its mitogenic activity, notably affecting pluripotent

stem cell proliferation and differentiation. We seeded the scaffolds with

bone marrow–derived mesenchymal stromal cells as progenitor cells to

evaluate their morphology and phenotypic expression. We also created

bilateral, fullthickness cranial defects in rabbits to investigate the osteogenic

effect of cultured mesenchymal stromal cells on bone regeneration in vivo.

Histomorphometry and histology demonstrated that the PEG-tethered

BMP-2 conjugate enhanced de novo bone formation after surgery.

Our work revealed the potential for biomimetic surface engineering by

entrapping signaling growth factor to stimulate osteogenesis. Our

technique may provide a new platform for bone-engineered stem cell therapies.

Scanning electron microscopy photomicrographs of the macroporous

poly(lactide-co-glycolide) (PLG) scaffold (A) and the surface of the

PLG- poly(ethylene glycol)-bone morphogenetic protein caffold(B).
Tsai CL, Chen CH, Liu TK. Lateral approach without ligament release in
total knee arthroplasty: new concepts in the surgical technique. Artificial
Organs 2001;25(8):638–643.
Yen HJ, Tseng CS, Hsu SH, Tsai CL. Evaluation of chondrocyte growth
in the highly porous scaffolds made by fused deposition manufacturing
(FDM) filled with type II collagen. Biomed Microdevices 2009; 11:615–624.
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