Sirkkunan Devindraan S/O, Muhamad Farina, Pingguan-Murphy Belinda
Department of Biomedical Engineering, Faculty of Engineering, Universiti Malaya, Kuala Lumpur 50603, Malaysia.
Gels. 2021 Sep 27;7(4):154. doi: 10.3390/gels7040154.
The use of neural scaffolds with a highly defined microarchitecture, fabricated with standard techniques such as electrospinning and microfluidic spinning, requires surgery for their application to the site of injury. To circumvent the risk associated with aciurgy, new strategies for treatment are sought. This has led to an increase in the quantity of research into injectable hydrogels in recent years. However, little research has been conducted into controlling the building blocks within these injectable hydrogels to produce similar scaffolds with a highly defined microarchitecture. "Magnetic particle string" and biomimetic amphiphile self-assembly are some of the methods currently available to achieve this purpose. Here, we developed a "magnetic anchor" method to improve the orientation of collagen fibres within injectable 3D scaffolds. This procedure uses GMNP (gold magnetic nanoparticle) "anchors" capped with CMPs (collagen mimetic peptides) that "chain" them to collagen fibres. Through the application of a magnetic field during the gelling process, these collagen fibres are aligned accordingly. It was shown in this study that the application of CMP functionalised GMNPs in a magnetic field significantly improves the alignment of the collagen fibres, which, in turn, improves the orientation of PC12 neurites. The growth of these neurite extensions, which were shown to be significantly longer, was also improved. The PC12 cells grown in collagen scaffolds fabricated using the "magnetic anchor" method shows comparable cellular viability to that of the untreated collagen scaffolds. This capability of remote control of the alignment of fibres within injectable collagen scaffolds opens up new strategic avenues in the research for treating debilitating neural tissue pathologies.
使用具有高度精细微结构的神经支架，通过静电纺丝和微流控纺丝等标准技术制造，其应用于损伤部位需要进行手术。为了规避与手术相关的风险，人们在寻求新的治疗策略。这导致近年来对可注射水凝胶的研究数量增加。然而，对于控制这些可注射水凝胶中的构建单元以产生具有高度精细微结构的类似支架的研究却很少。“磁性粒子串”和仿生两亲分子自组装是目前可用于实现这一目的的一些方法。在这里，我们开发了一种“磁性锚定”方法来改善可注射3D支架内胶原纤维的排列。该过程使用用CMPs（胶原模拟肽）封端的GMNP（金磁性纳米粒子）“锚”将它们“连接”到胶原纤维上。通过在凝胶化过程中施加磁场，这些胶原纤维会相应地排列。本研究表明，在磁场中应用CMP功能化的GMNPs可显著改善胶原纤维的排列，进而改善PC12神经突的取向。这些神经突延伸的生长也得到了改善，其长度明显更长。在使用“磁性锚定”方法制造的胶原支架中生长的PC12细胞显示出与未处理的胶原支架相当的细胞活力。这种对可注射胶原支架内纤维排列进行远程控制的能力为治疗衰弱性神经组织病变的研究开辟了新的战略途径。
