期刊
JOURNAL OF TISSUE ENGINEERING AND REGENERATIVE MEDICINE
卷 8, 期 7, 页码 521-533出版社
WILEY
DOI: 10.1002/term.1549
关键词
osteochondral repair; alginate-PLGA scaffold; controlled release; histology; BMP-2; TGF beta 1
类别
资金
- Ministry of Science and Technology [MAT2011-23819]
- Hospiten Holding S.L. [Convenio CI02320701]
Regeneration of cartilage defects can be accelerated by localized delivery of appropriate growth factors (GFs) from scaffolds. In the present study we analysed the in vitro and in vivo release rates and delivery efficacies of transforming growth factor-beta 1 (TGF beta 1) and bone morphogenetic protein-2 (BMP-2) from a bilayered system, applied for osteochondral defect repair in a rabbit model. A bone-orientated, porous PLGA cylinder was overlaid with GF containing PLGA microspheres, dispersed in an alginate matrix. Four microsphere formulations were incorporated: (a) blank ones; (b) microspheres containing 50 ng TGF beta 1; (c) microspheres containing 2.5 mu g BMP-2; and (d) microspheres containing 5 mu g BMP-2. Release kinetics and tissue distributions were determined using iodinated (I-125) GFs. Bioactivity of in vitro released BMP-2 and TGFb1 was confirmed in cell-based assays. In vivo release profiles indicated good GF release control. 20% of BMP-2 and 15% of TGF beta 1 were released during the first day. Virtually the total dose was delivered at the end of week 6. Significant histological differences were observed between untreated and GF-treated specimens, there being especially relevant short-term outcomes with 50 ng TGF beta 1 and 5 mu g BMP-2. Although the evaluation scores for the newly formed cartilage did not differ significantly, 5 mu g BMP-2 gave rise to higher quality cartilage with improved surface regularity, tissue integration and increased collagen-type II and aggrecan immunoreactivity 2 weeks post-implantation. Hence, the bilayered system controlled GF release rates and led to preserved cartilage integrity from 12 weeks up to at least 24 weeks. Copyright (C) 2012 John Wiley & Sons, Ltd.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据