Neural matchsticks for 3D neural network assembly

This conference proceeding describes a three-dimensional (3D) neural network formed by neural matchsticks assembly. The neural matchsticks are cut from a meter-long neural microfiber that is made by core-shell hydrogel microfibers encapsulating neural stem cells (NSCs). For fabrication of 3D neural network, we assembled the neural matchsticks into a PDMS mold and cultured. Since neural matchsticks are initially covered with alginate shell, cells sprout out from only the edge of the neural matchsticks, and connected with each other. We demonstrated several types of connection angles using neural matchsticks. Alginate shell-covered neural network has handleability and high mechanical strength compared to neural tissue. After alginate shell is dissolved, we can obtain a 3D neural tissue that consists of only cells (neurons and glial cells). We believe that neural matchsticks assembly enables the fabrication of complex 3D neural network in vitro, and that this system is a powerful approach for various fields including neural tissue engineering, analysis of 3D neural network how they fire action potential, and pharmacological assay for drug screening.