The kinetic and biological activity of different loaded rhBMP-2 calcium phosphate cement implants in rats
| Autor: | Bodde, E.W.H., Boerman, O.C., Russel, F.G.M., Mikos, A.G., Spauwen, P.H.M., Jansen, J.A. |
|---|---|
| Rok vydání: | 2008 |
| Předmět: |
Pathogenesis and modulation of inflammation [N4i 1]
Tissue engineering and reconstructive surgery [UMCN 4.3] Renal disorders [UMCN 5.4] Metabolism transport and motion [NCMLS 2] Immune Regulation [NCMLS 2] Translational research [ONCOL 3] Membrane transport and intracellular motility [NCMLS 5] Aetiology screening and detection [ONCOL 5] Synthetic Organic Chemistry Microbial pathogenesis and host defense [UMCN 4.1] Tissue engineering and pathology [NCMLS 3] Renal disorder [IGMD 9] Immunity infection and tissue repair [NCMLS 1] |
| Zdroj: | Journal of Biomedical Materials Research Part A, 87, 3, pp. 780-91 Journal of Biomedical Materials Research Part A, 87, 780-91 |
| ISSN: | 1549-3296 |
| Popis: | Contains fulltext : 70710.pdf (Publisher’s version ) (Open Access) The healing of large bone defects can be improved by osteogenic bone graft substitutes, due to growth factor inclusion. A sustained release of these growth factors provides more efficient bioactivity when compared with burst release and might reduce the dose required for bone regeneration, which is desirable for socioeconomical and safety reasons. In this study, we compared different rhBMP-2 loadings in a sustained release system of CaP cement and PLGA-microparticles and were able to couple kinetic to biological activity data. Fifty-two rats received a critical-size cranial defect, which was left open or filled with the cement composites. The implants consisted of plain, high, and five-fold lower dose rhBMP-2 groups. Implantation time was 4 and 12 weeks. Longitudinal in vivo release was monitored by scintigraphic imaging of (131)I-labeled rhBMP-2. Quantitative analysis of the scintigraphic images revealed a sustained release of (131)I-rhBMP-2 for both doses, with different release profiles between the two loadings. However, around 70% of the initial dose was retained in both implant formulations. Although low amounts of rhBMP-2 were released (2.4 +/- 0.8 mug in 5 weeks), histology showed defect bridging in the high-dose implants. Release out of the low-dose implants was not sufficient to enhance bone formation. Implant degradation was limited in all formulations, but was mainly seen in the high-dose group. Low amounts of sustained released rhBMP-2 were sufficient to bridge critically sized defects. A substantial amount of rhBMP-2 was retained in the implants because of the slow release rate and the limited degradation. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text