A biodegradable vascularizing membrane: A feasibility study
A biodegradable vascularizing membrane: A feasibility study
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DOI：
10.1016/j.actbio.2007.03.003
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发表时间：
2007-09-01
影响因子：
9.7
通讯作者：
Ameer, Guillermo A.
中科院分区：
文献类型：
--
作者：
Kaushiva, Anchal;Turzhitsky, Vladimir M.;Ameer, Guillermo A.
再生医学和体内生物传感器的应用需要形成成熟的血管网络才能长期成功。这项研究调查了可生物降解的多孔膜是否可以诱导血管化纤维囊膜的形成，如果是的话，降解动力学对新生血管的影响。采用溶剂浇铸/盐析法制备了聚L-乳酸(PLLA)和聚(DL-乳酸-乙醇酸)共聚物(PLGA)膜。具体而言，使用PLLA、PLGA 75：25和PLGA 50：50聚合物来改变降解动力学。膜的设计平均孔径为60微米，因为这种孔径被证明是在不可降解的聚合物材料周围诱导血管形成的最佳孔径。在体外降解过程中的几个时间点，用扫描电子显微镜对膜样品进行成像，以评估孔结构的任何变化。通过测量植入物附近形成的纤维包膜内的血管形成，在Spraogue-Dawley大鼠身上评估了这种膜的体内性能。将膜100微米内的血管密度与正常组织以及商业可获得的血管化膜TheraCyte周围的血管密度进行比较。用四维弹性光散射法测量含有膜的组织中的血红蛋白含量，作为一种评估组织灌注量的新方法。这项研究的结果表明，与快速降解的膜相比，慢速降解的膜可以诱导更多的新生血管和更薄的纤维膜。这些结果可能是由于降解较慢的膜周围最初巨噬细胞数量的增加以及其初始孔结构的保持。(C)2007年Acta Materialia Inc.由爱思唯尔有限公司出版。保留所有权利。
Regenerative medicine and in vivo biosensor applications require the formation of mature vascular networks for long-term success. This study investigated whether biodegradable porous membranes could induce the formation of a vascularized fibrous capsule and, if so, the effect of degradation kinetics on neovascularization. Poly(L-lactic acid) (PLLA) and poly(DL-lactic-co-glycolic) acid (PLGA) membranes were created by a solvent casting/salt leaching method. Specifically, PLLA, PLGA 75:25 and PLGA 50:50 polymers were used to vary degradation kinetics. The membranes were designed to have an average 60 mu m pore diameter, as this pore size has been shown to be optimal for inducing blood vessel formation around nondegradable polymer materials. Membrane samples were imaged by scanning electron microscopy at several time points during in vitro degradation to assess any changes in pore structure. The in vivo performance of the membranes was assessed in Sprague-Dawley rats by measuring vascularization within the fibrous capsule that forms adjacent to implants. The vascular density within 100 mu m of the membranes was compared with that seen in normal tissue, and to that surrounding the commercially available vascularizing membrane TheraCyte. The hemoglobin content of tissue containing the membranes was measured by four-dimensional elastic light scattering as a novel method to assess tissue perfusion. Results from this study show that slow-degrading membranes induce greater amounts of neovascularization and a thinner fibrous capsule relative to fast degrading membranes. These results may be due both to an initially increased number of macrophages surrounding the slower degrading membranes and to the maintenance of their initial pore structure. (c) 2007 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.