Transcription Factor-Based Fate Specification and Forward Programming for Neural Regeneration

Abstract

Traditionally, in vitro generation of donor cells for brain repair has been dominated by the application of extrinsic growth factors and morphogens. Recent advances in cell engineering strategies such as reprogramming of somatic cells into induced pluripotent stem cells and direct cell fate conversion have impressively demonstrated the feasibility to manipulate cell identities by the overexpression of cell fate-determining transcription factors. These strategies are now increasingly implemented for transcription factorguided differentiation of neural precursors and forward programming of pluripotent stem cells toward specific neural subtypes. This review covers major achievements, pros and cons, as well as future prospects of transcription factor-based cell fate specification and the applicability of these approaches for the generation of donor cells for brain repair.

NGN2 mmRNA-Based Transcriptional Programming in Microfluidic Guides hiPSCs Toward Neural Fate With Multiple Identities

“…The second one involves a rapid and efficient differentiation by overexpression of specific transcription factors (TFs), which are master regulators of the cell lineage of interest ( Son et al, 2011 ; Mertens et al, 2016 ). This last method, named TF programming, allows a faster generation of the target cell population bypassing or shortening many developmental stages that cell experiences during differentiation in vivo ( Flitsch et al, 2020 ). The milestone in the TF programming was reached from Zhang and colleagues who proved that Neurogenin2 (NGN2) alone was able to program pluripotent stem cells into functional neuronal like-cells in 2 weeks ( Zhang et al, 2013 ).…”

“…However, the integration of foreign DNA in the host genome can lead to potential problems linked to genome modifications, random integrations in regulatory or coding sequences, difficulties in silencing the expression of exogenous transcript and uncontrolled expression level. Even if some of these hurdles have been addressed by countermeasures (such as TALENs or CRISPR/Cas9 strategies to better control integration sites), integration is strongly associated with safety limitations for any clinical translation ( Flitsch et al, 2020 ).…”

Sanfilippo Syndrome: Molecular Basis, Disease Models and Therapeutic Approaches

“…Findings relevant in animal models might not be important in the context of human physiology, pointing out the importance of generating human cellular models to complement the existing animal models. In the last years, several Sanfilippo-iPSC lines have been established and, in combination with faster and improved protocols to generate relevant cell types in 2D and 3D cultures [ 125 , 126 , 127 ], will contribute to expand our understanding of the molecular and cellular mechanisms of the disease. In addition, iPSC-derived brain cells will be very useful in drug screening studies to identify possible drug candidates with the potential to treat human brain cells.…”

Understanding and Engineering Chromatin as a Dynamical System across Length and Timescales

“…Consequently, efforts to drive cellular transitions have focused on transcription factor cocktails to induce specific cell fates. While directed differentiation via small molecules and exogenous factors represents the most common method of generating somatic cells types from iPSCs, overexpression of lineage-specifying transcription factors is increasingly employed to guide cells to specific identities (Flitsch et al, 2020;Nickolls et al, 2020;Wang et al, 2017). The development of synthetic transcription factors expands the ensemble of tools beyond native transcription factors to enable precise single-locus and multi-locus targeting of regulatory nodes.…”