Department of Mechanical and Aerospace Engineering, The George Washington University, Washington, DC 20052, USA.
Nanotechnology. 2013 Sep 13;24(36):365102. doi: 10.1088/0957-4484/24/36/365102. Epub 2013 Aug 20.
Cartilage tissue is a nanostructured tissue which is notoriously hard to regenerate due to its extremely poor inherent regenerative capacity and complex stratified architecture. Current treatment methods are highly invasive and may have many complications. Thus, the goal of this work is to use nanomaterials and nano/microfabrication methods to create novel biologically inspired tissue engineered cartilage scaffolds to facilitate human bone marrow mesenchymal stem cell (MSC) chondrogenesis. To this end we utilized electrospinning to design and fabricate a series of novel 3D biomimetic nanostructured scaffolds based on hydrogen (H2) treated multi-walled carbon nanotubes (MWCNTs) and biocompatible poly(L-lactic acid) (PLLA) polymers. Specifically, a series of electrospun fibrous PLLA scaffolds with controlled fiber dimension were fabricated in this study. In vitro MSC studies showed that stem cells prefer to attach in the scaffolds with smaller fiber diameter. More importantly, the MWCNT embedded scaffolds showed a drastic increase in mechanical strength and a compressive Young's modulus matching to natural cartilage. Furthermore, our MSC differentiation results demonstrated that incorporation of the H2 treated carbon nanotubes and poly-L-lysine coating can induce more chondrogenic differentiations of MSCs than controls. After two weeks of culture, PLLA scaffolds with H2 treated MWCNTs and poly-L-lysine can achieve the highest glycosaminoglycan synthesis, making them promising for further exploration for cartilage regeneration.
软骨组织是一种纳米结构组织,由于其极其有限的内在再生能力和复杂的分层结构,因此很难再生。目前的治疗方法具有高度侵入性,并且可能会有许多并发症。因此,这项工作的目标是使用纳米材料和纳米/微加工方法来创建新颖的受生物启发的组织工程软骨支架,以促进人骨髓间充质干细胞(MSC)的软骨生成。为此,我们利用静电纺丝设计并制造了一系列基于氢(H2)处理的多壁碳纳米管(MWCNT)和生物相容性聚(L-丙交酯)(PLLA)聚合物的新型 3D 仿生纳米结构支架。具体来说,本研究中制造了一系列具有受控纤维尺寸的电纺纤维 PLLA 支架。体外 MSC 研究表明,干细胞更喜欢附着在纤维直径较小的支架上。更重要的是,MWCNT 嵌入的支架的机械强度大大提高,并且压缩杨氏模量与天然软骨相匹配。此外,我们的 MSC 分化结果表明,与对照相比,H2 处理的碳纳米管和聚-L-赖氨酸涂层的掺入可以诱导 MSC 更多的软骨分化。培养两周后,具有 H2 处理的 MWCNT 和聚-L-赖氨酸的 PLLA 支架可以实现最高的糖胺聚糖合成,这使它们有望进一步探索软骨再生。