Published online Jul 26, 2019. doi: 10.4252/wjsc.v11.i7.431
Peer-review started: February 24, 2019
First decision: June 5, 2019
Revised: June 7, 2019
Accepted: June 27, 2019
Article in press: June 27, 2019
Published online: July 26, 2019
Processing time: 154 Days and 1.4 Hours
Cell therapy offers great promises in replacing the neurons lost due to neurodegenerative diseases or injuries. However, a key challenge is the cellular source for transplantation which is often limited by donor availability. Direct reprogramming provides an exciting avenue to generate specialized neuron subtypes in vitro, which have the potential to be used for autologous transplantation, as well as generation of patient-specific disease models in the lab for drug discovery and testing gene therapy. Here we present a detailed review on transcription factors that promote direct reprogramming of specific neuronal subtypes with particular focus on glutamatergic, GABAergic, dopaminergic, sensory and retinal neurons. We will discuss the developmental role of master transcriptional regulators and specification factors for neuronal subtypes, and summarize their use in promoting direct reprogramming into different neuronal subtypes. Furthermore, we will discuss up-and-coming technologies that advance the cell reprogramming field, including the use of computational prediction of reprogramming factors, opportunity of cellular reprogramming using small chemicals and microRNA, as well as the exciting potential for applying direct reprogramming in vivo as a novel approach to promote neuro-regeneration within the body. Finally, we will highlight the clinical potential of direct reprogramming and discuss the hurdles that need to be overcome for clinical translation.
Core tip: Direct reprogramming represents an innovative technology to generate neurons in the lab, which can be used for cell therapy, drug screening and disease modeling for neurodegenerative diseases. In this review we will discuss the current advance in identifying transcription factors to promote direct reprogramming of specialized neuronal subtypes, including glutamatergic, GABAergic, dopaminergic, sensory and retinal neurons. We will also discuss the hurdles that need to be overcome for clinical translation.