Expert Tips On Building a 3-Dimensional hipsc-derived cortical neuronal network

Building a 3-Dimensional human iPSC-derived cortical neuronal network: You need a scaffold to build a brain

The cerebral neocortex is the most newly-evolved region of the brain. In humans it has undergone dramatic progenitor expansion, subtype specification, and network formation.

Human induced pluripotent stem cell (iPSC)-derived neural progenitors have shown an in vivo-like ability to self-organise & promote cerebral cortical lineage determination under minimal growth factor conditions (Shi et al., 2012a; Renner et al., 2017). However, although the cortex’s laminated organisation represents a great functional significance in vivo, neocortical networks are rarely modelled in vitro using 3D cell culture, or omit key neural subtypes (Kirwan et al 2015).

Despite recent developments in tissue modelling, e.g. organoids (Kelava & Lancaster, 2016), 3D models exhibit high variability – impeding exploration of network topography.

Alongside advancements in stem cell biology, progress in nanoscale printing, volumetric imaging & network analysis presents a unique opportunity to combine these fields in search of a better model. Building on this, the MESO-BRAIN project aims to develop a 3D cortical model using expertise from each field (Figure 1) – here we present initial findings.

Our first aim was to determine a suitable material for use in scaffold fabrication – this included investigating potential toxicity, optimal coating reagents, compatibility with optical imaging & two-photon polymerisation processing.