Evaluation of the use of neuroblastoma cell line Neuro2a as a study model for inhibition of axonal growth in 2D and 3D

Abstract

The central nervous system (CNS) exhibits a limited regeneration process due to the formation of a glial scar after the occurrence of an injury. The glial scar acts as a barrier against the entrance of neuroblasts inside the injury, making it impossible to repair the neural synapses of that zone. The glial scar is formed by reactive astrocytes and oligodendrocytes that produce inhibitory molecules of axonal growth and migration of neuroprogenitors. There are known four molecules produced by these glial cells which have an inhibitory function: Nogo, OMGp (oligodendrocyte myelin glycoprotein), MAG myelin-associated glycoprotein) and CSPG (chondroitin sulfate proteoglycans). The CS side chains are responsible for the inhibitory properties when bound to the protein tyrosine phosphatase sigma (RPTPÃ), which acts as a transmembrane receptor. When the interaction of CSPG and RPTPÃ happens, it starts intracellular signaling, activating multiple pathways, including the GTPase Rho/ROCK signaling pathway, which results in suppression of axonal growth in neurons. This inhibition, combined with the influence of Nogo, OMGp, and MAG, results in the limited regeneration of neurons after the injury in the CNS. In order to reduce the usage of animals in experiments, our laboratory has been investing in the fabrication of neural tissues using 3D bioprinting, aiming to use these tissues as a more complex experimental model than cell culture in 2D. The purpose of this work is to evaluate if the neuroblastoma cell line Neuro2a is a suitable model to study the role of CS in the inhibitory axon growth in a 2D system and compare it with a biomimetic tissue produced by 3D bioprinting. (AU)