Lu Panjian, Chen Zhiying, Wu Mingjun, Feng Shuyue, Chen Sailing, Cheng Xiyang, Zhao Yahong, Liu Xingyu, Gong Leilei, Bian Lijing, Yi Sheng, Wang Hongkui
Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Medical School of Nantong University, Nantong University, 19 Qixiu Road, Nantong, Jiangsu 226001, China.
Imperial College of Science, Technology and Medicine, London SW7 2AZ, United Kingdom.
Burns Trauma. 2024 Dec 10;12:tkae049. doi: 10.1093/burnst/tkae049. eCollection 2024.
The extracellular matrix (ECM) provides essential physical support and biochemical cues for diverse biological activities, including tissue remodelling and regeneration, and thus is commonly applied in the construction of artificial peripheral nerve grafts. Nevertheless, the specific functions of essential peripheral nerve ECM components have not been fully determined. Our research aimed to differentially represent the neural activities of main components of ECM on peripheral nerve regeneration.
Schwann cells from sciatic nerves and neurons from dorsal root ganglia were isolated and cultured . The cells were seeded onto noncoated dishes, Matrigel-coated dishes, and dishes coated with the four major ECM components fibronectin, laminin, collagen I, and collagen IV. The effects of these ECM components on Schwann cell proliferation were determined via methylthiazolyldiphenyl-tetrazolium bromide (MTT), Cell Counting Kit-8, and 5-ethynyl-2'-deoxyuridine (EdU) assays, whereas their effects on cell migration were determined via wound healing and live-cell imaging. Neurite growth in neurons cultured on different ECM components was observed. Furthermore, the two types of collagen were incorporated into chitosan artificial nerves and used to repair sciatic nerve defects in rats. Immunofluorescence analysis and a behavioural assessment, including gait, electrophysiology, and target muscle analysis, were conducted.
ECM components, especially collagen I, stimulated the DNA synthesis and movement of Schwann cells. Direct measurement of the neurite lengths of neurons cultured on ECM components further revealed the beneficial effects of ECM components on neurite outgrowth. Injection of collagen I into chitosan and poly(lactic-co-glycolic acid) artificial nerves demonstrated that collagen I facilitated axon regeneration and functional recovery after nerve defect repair by stimulating the migration of Schwann cells and the formation of new blood vessels. In contrast, collagen IV recruited excess fibroblasts and inflammatory macrophages and thus had disadvantageous effects on nerve regeneration.
These findings reveal the modulatory effects of specific ECM components on cell populations of peripheral nerves, reveal the contributing roles of collagen I in microenvironment construction and axon regeneration, and highlight the use of collagen I for the healing of injured peripheral nerves.
细胞外基质（ECM）为包括组织重塑和再生在内的多种生物活动提供重要的物理支持和生化信号，因此常用于人工周围神经移植物的构建。然而，周围神经ECM主要成分的具体功能尚未完全明确。我们的研究旨在区分ECM主要成分对周围神经再生的神经活动影响。
分离并培养坐骨神经中的雪旺细胞和背根神经节中的神经元。将细胞接种到未包被的培养皿、基质胶包被的培养皿以及包被有四种主要ECM成分（纤连蛋白、层粘连蛋白、I型胶原蛋白和IV型胶原蛋白）的培养皿上。通过甲基噻唑基二苯基溴化四氮唑（MTT）、细胞计数试剂盒-8和5-乙炔基-2'-脱氧尿苷（EdU）检测来确定这些ECM成分对雪旺细胞增殖的影响，而通过伤口愈合和活细胞成像来确定它们对细胞迁移的影响。观察在不同ECM成分上培养的神经元的轴突生长情况。此外，将这两种类型的胶原蛋白掺入壳聚糖人工神经中，并用于修复大鼠的坐骨神经缺损。进行免疫荧光分析和行为评估，包括步态、电生理学和靶肌肉分析。
ECM成分，尤其是I型胶原蛋白，刺激了雪旺细胞的DNA合成和移动。对在ECM成分上培养的神经元轴突长度的直接测量进一步揭示了ECM成分对轴突生长的有益影响。将I型胶原蛋白注入壳聚糖和聚乳酸-羟基乙酸共聚物人工神经中表明，I型胶原蛋白通过刺激雪旺细胞迁移和新血管形成，促进了神经缺损修复后的轴突再生和功能恢复。相比之下，IV型胶原蛋白募集了过多的成纤维细胞和炎性巨噬细胞，因此对神经再生有不利影响。
这些发现揭示了特定ECM成分对周围神经细胞群的调节作用，揭示了I型胶原蛋白在微环境构建和轴突再生中的作用，并突出了I型胶原蛋白在损伤周围神经愈合中的应用。
