Olsen Timothy R, Casco Megan, Herbst Austin, Evans Grace, Rothermel Taylor, Pruett Lauren, Reid Jared, Barry Kelly, Jaeggli Michael P, Simionescu Dan T, Visconti Richard P, Alexis Frank
Department of Bioengineering, Clemson University, 301 Rhodes Research Center, Clemson, SC 29634, USA.
Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, 173 Ashley Avenue, 601 Basic Science Building, Charleston, SC 29425, USA.
Bioengineering (Basel). 2016 Nov 16;3(4):29. doi: 10.3390/bioengineering3040029.
Cellular spheroids were studied to determine their use as "bioinks" in the biofabrication of tissue engineered constructs. Specifically, magnetic forces were used to mediate the cyclic longitudinal stretching of tissues composed of Janus magnetic cellular spheroids (JMCSs), as part of a post-processing method for enhancing the deposition and mechanical properties of an extracellular matrix (ECM). The purpose was to accelerate the conventional tissue maturation process via novel post-processing techniques that accelerate the functional, structural, and mechanical mimicking of native tissues. The results of a forty-day study of JMCSs indicated an expression of collagen I, collagen IV, elastin, and fibronectin, which are important vascular ECM proteins. Most notably, the subsequent exposure of fused tissue sheets composed of JMCSs to magnetic forces did not hinder the production of these key proteins. Quantitative results demonstrate that cyclic longitudinal stretching of the tissue sheets mediated by these magnetic forces increased the Young's modulus and induced collagen fiber alignment over a seven day period, when compared to statically conditioned controls. Specifically, the elastin and collagen content of these dynamically-conditioned sheets were 35- and three-fold greater, respectively, at seven days compared to the statically-conditioned controls at three days. These findings indicate the potential of using magnetic forces in tissue maturation, specifically through the cyclic longitudinal stretching of tissues.
研究了细胞球体，以确定其在组织工程构建体生物制造中作为“生物墨水”的用途。具体而言，利用磁力介导由Janus磁性细胞球体（JMCS）组成的组织的周期性纵向拉伸，作为一种后处理方法的一部分，以增强细胞外基质（ECM）的沉积和机械性能。目的是通过加速天然组织功能、结构和机械模拟的新型后处理技术来加速传统的组织成熟过程。对JMCS进行的为期40天的研究结果表明，胶原蛋白I、胶原蛋白IV、弹性蛋白和纤连蛋白有表达，这些都是重要的血管ECM蛋白。最值得注意的是，由JMCS组成的融合组织片随后暴露于磁力下并不妨碍这些关键蛋白的产生。定量结果表明，与静态对照相比，在七天时间里，由这些磁力介导的组织片的周期性纵向拉伸提高了杨氏模量并诱导了胶原纤维排列。具体而言，与三天的静态对照相比，这些动态处理的组织片在七天时的弹性蛋白和胶原蛋白含量分别高出35倍和三倍。这些发现表明了在组织成熟中利用磁力的潜力，特别是通过组织的周期性纵向拉伸。
