Garrigues N William, Little Dianne, Sanchez-Adams Johannah, Ruch David S, Guilak Farshid
Department of Orthopaedic Surgery, Duke University Medical Center, Durham, North Carolina, 27710; Department of Biomedical Engineering, Duke University Medical Center, Durham, North Carolina, 27710.
J Biomed Mater Res A. 2014 Nov;102(11):3998-4008. doi: 10.1002/jbm.a.35068. Epub 2014 Jan 9.
Macroscale scaffolds created from cartilage-derived matrix (CDM) demonstrate chondroinductive or chondro-inductive properties, but many fabrication methods do not allow for control of nanoscale architecture. In this regard, electrospun scaffolds have shown significant promise for cartilage tissue engineering. However, nanofibrous materials generally exhibit a relatively small pore size and require techniques such as multilayering or the inclusion of sacrificial fibers to enhance cellular infiltration. The objectives of this study were (1) to compare multilayer to single-layer electrospun poly(ɛ-caprolactone) (PCL) scaffolds for cartilage tissue engineering, and (2) to determine whether incorporation of CDM into the PCL fibers would enhance chondrogenesis by human adipose-derived stem cells (hASCs). PCL and PCL-CDM scaffolds were prepared by sequential collection of 60 electrospun layers from the surface of a grounded saline bath into a single scaffold, or by continuous electrospinning onto the surface of a grounded saline bath and harvest as a single-layer scaffold. Scaffolds were seeded with hASCs and evaluated over 28 days in culture. The predominant effects on hASCs of incorporation of CDM into scaffolds were to stimulate sulfated glycosaminoglycan synthesis and COL10A1 gene expression. Compared with single-layer scaffolds, multilayer scaffolds enhanced cell infiltration and ACAN gene expression. However, compared with single-layer constructs, multilayer PCL constructs had a much lower elastic modulus, and PCL-CDM constructs had an elastic modulus approximately 1% that of PCL constructs. These data suggest that multilayer electrospun constructs enhance homogeneous cell seeding, and that the inclusion of CDM stimulates chondrogenesis-related bioactivity.
由软骨衍生基质（CDM）制成的宏观支架具有软骨诱导特性，但许多制造方法无法控制纳米级结构。在这方面，电纺支架在软骨组织工程中显示出巨大潜力。然而，纳米纤维材料通常孔径相对较小，需要多层铺设或加入牺牲纤维等技术来增强细胞浸润。本研究的目的是：（1）比较用于软骨组织工程的多层与单层电纺聚己内酯（PCL）支架；（2）确定将CDM掺入PCL纤维中是否会增强人脂肪来源干细胞（hASC）的软骨形成。PCL和PCL-CDM支架的制备方法如下：从接地盐浴表面依次收集60层电纺层到单个支架中，或将其连续电纺到接地盐浴表面并作为单层支架收集。将hASC接种到支架上并在培养28天期间进行评估。将CDM掺入支架对hASC的主要影响是刺激硫酸化糖胺聚糖合成和COL10A1基因表达。与单层支架相比，多层支架增强了细胞浸润和ACAN基因表达。然而，与单层构建体相比，多层PCL构建体的弹性模量要低得多，而PCL-CDM构建体的弹性模量约为PCL构建体的1%。这些数据表明，多层电纺构建体可增强细胞均匀接种，并且掺入CDM可刺激与软骨形成相关的生物活性。
