Lantoine Joséphine, Grevesse Thomas, Villers Agnès, Delhaye Geoffrey, Mestdagh Camille, Versaevel Marie, Mohammed Danahe, Bruyère Céline, Alaimo Laura, Lacour Stéphanie P, Ris Laurence, Gabriele Sylvain
Mechanobiology & Soft Matter Group, Laboratoire Interfaces et Fluides Complexes, Centre d'Innovation et de Recherche en Matériaux Polymères (CIRMAP), Research Institute for Biosciences, Université de Mons, 20, Place du Parc, B-7000 Mons, Belgium.
Department of Neuroscience, University of Mons, Belgium.
Biomaterials. 2016 May;89:14-24. doi: 10.1016/j.biomaterials.2016.02.041. Epub 2016 Feb 26.
The ability to construct easily in vitro networks of primary neurons organized with imposed topologies is required for neural tissue engineering as well as for the development of neuronal interfaces with desirable characteristics. However, accumulating evidence suggests that the mechanical properties of the culture matrix can modulate important neuronal functions such as growth, extension, branching and activity. Here we designed robust and reproducible laminin-polylysine grid micropatterns on cell culture substrates that have similar biochemical properties but a 100-fold difference in Young's modulus to investigate the role of the matrix rigidity on the formation and activity of cortical neuronal networks. We found that cell bodies of primary cortical neurons gradually accumulate in circular islands, whereas axonal extensions spread on linear tracks to connect circular islands. Our findings indicate that migration of cortical neurons is enhanced on soft substrates, leading to a faster formation of neuronal networks. Furthermore, the pre-synaptic density was two times higher on stiff substrates and consistently the number of action potentials and miniature synaptic currents was enhanced on stiff substrates. Taken together, our results provide compelling evidence to indicate that matrix stiffness is a key parameter to modulate the growth dynamics, synaptic density and electrophysiological activity of cortical neuronal networks, thus providing useful information on scaffold design for neural tissue engineering.
神经组织工程以及开发具有理想特性的神经元接口都需要具备在体外轻松构建具有特定拓扑结构的原代神经元网络的能力。然而，越来越多的证据表明，培养基质的机械性能可以调节重要的神经元功能，如生长、延伸、分支和活性。在这里，我们在细胞培养底物上设计了坚固且可重复的层粘连蛋白 - 聚赖氨酸网格微图案，这些底物具有相似的生化特性，但杨氏模量相差100倍，以研究基质刚度对皮质神经元网络形成和活性的作用。我们发现，原代皮质神经元的细胞体逐渐聚集在圆形岛中，而轴突延伸则在线性轨道上扩散以连接圆形岛。我们的研究结果表明，在柔软底物上皮质神经元的迁移增强，导致神经元网络形成更快。此外，在坚硬底物上突触前密度高出两倍，并且在坚硬底物上动作电位和微小突触电流的数量持续增加。综上所述，我们的结果提供了令人信服的证据，表明基质刚度是调节皮质神经元网络生长动力学、突触密度和电生理活性的关键参数，从而为神经组织工程的支架设计提供了有用信息。
