Advances in 3D neuronal cell culture

In this contribution, the authors present our advances in three-dimensional (3D) neuronal cell culture platform technology contributing to controlled environments for microtissue engineering and analysis of cellular physiological and pathological responses. First, a micromachined silicon sieving structure is presented as key parameter for a modified version of a planar tissue culture, allowing seeding of single neurons in pyramidal shaped pores by a hydrodynamic sieve flow. Second, a nanogroove-hydrogel interface is presented as a more biomimetic in vivo representation of neuronal tissues, where 3D culturing is required to reproduce the layered tissue organization, which is observed in the microenvironment of the brain. To further our understanding of uniquely nanopatterned interfaces, the authors evaluated 3D neuronal outgrowth into Matrigel atop of primary cortical cell (CTX) cultured on nanogrooves. The interface facilitates conformation of cell somas and aligned outgrowth in 3D with outgrowth alignment preserved in Matrigel up to 6 μm above the nanogrooved substrate, which has a pattern height of just 108 nm. Finally, with the view to incorporate these guided culture interfaces in our previously designed hybrid Polydimethylsiloxane bioreactor, the authors have also explored 3D cellular culture matrix as a variable in such systems. By analyzing the effect of different gel matrices (Matrigel, PuraMatrix, and collagen-I) on the neuron model cell line SH-SY5Y, the authors bring together the ability to guide neuronal growth in spatially standardized patterns and within a bioreactor potentially coupled to an array of single cells that could facilitate readout of such complex cultures by integration with existing technologies (e.g., microelectrode arrays). Various combinations of these novel techniques can be made and help to design experimental studies to investigate how changes in cell morphology translate to changes in function but also how changes in connectivity relate to changes in electrophysiology. These latest advancements will lead to the development of improved, highly organized in vitro assays to understand, mimic, and treat brain disorders.