Conducting Polymer Mediated Electrical Stimulation Induces Multilineage Differentiation with Robust Neuronal Fate Determination of Human Induced Pluripotent Stem Cells

Abstract

Electrical stimulation is increasingly being used to modulate human cell behaviour for biotechnological research and therapeutics. Electrically conductive polymers (CPs) such as polypyrrole (PPy) are amenable to in vitro and in vivo cell stimulation, being easy to synthesise with different counter ions (dopants) to augment biocompatibility and cell-effects. Extending our earlier work, which showed that CP-mediated electrical stimulation promotes human neural stem cell differentiation, here we report using electroactive PPy containing the anionic dopant dodecylbenzenesulfonate (DBS) to modulate the fate determination of human induced pluripotent stem cells (iPSCs). Remarkably, the stimulation without conventional chemical inducers resulted in the iPSCs differentiating to cells of the three germ lineages—endoderm, ectoderm, and mesoderm. The unstimulated iPSC controls remained undifferentiated. Phenotypic characterisation further showed a robust induction to neuronal fate with electrical stimulation, again without customary chemical inducers. Our findings add to the growing body of evidence supporting the use of electrical stimulation to augment stem cell differentiation, more specifically, pluripotent stem cell differentiation, and especially neuronal induction. Moreover, we have shown the versatility of electroactive PPy as a cell-compatible platform for advanced stem cell research and translation, including identifying novel mechanisms of fate regulation, tissue development, electroceuticals, and regenerative medicine.

Bioelectric Potential in Next-Generation Organoids: Electrical Stimulation to Enhance 3D Structures of the Central Nervous System

“…Furthermore, when transplanted into injured spinal cord, NPCs from stimulated mESC-derived cells were more capable of incorporating and forming neural cells than unstimulated controls ( Yamada et al, 2007 ). Previous findings of EF-induced differentiation and fate determination in studies using primary or human NSC lines, were similarly replicated in iPSC-derived neuronal cultures ( Stewart et al, 2015 ; Tomaskovic-Crook et al, 2019 ; Tomaskovic-Crook et al, 2020 ; Oh et al, 2021 ). Specifically, iPSCs were cultured in clusters in suspension within a polymer, followed by neuronal differentiation and electrical stimulation.…”

“…Specifically, iPSCs were cultured in clusters in suspension within a polymer, followed by neuronal differentiation and electrical stimulation. The resultant neuronal cultures contained more MAP2+ neurons and fewer glial cells than unstimulated counterparts ( Tomaskovic-Crook et al, 2020 ).…”

“…Since PSCs are prone to genomic and epigenetic instability, there may be hesitancy to apply exogenous stimuli which could adversely alter pluripotent capacity. However, exogenously stimulated human ESCs and iPSCs have been demonstrated to give rise to all three germ layers, with accelerated or enhanced differentiation capacity ( Yamada et al, 2007 ; Tomaskovic-Crook et al, 2020 ). In vivo, endogenous EFs are present at stages overlapping with the division of pluripotent embryonic stem cells ( Levin et al, 2002 ).…”

Engineering in vitro human neural tissue analogs by 3D bioprinting and electrostimulation

“… 45,177 This technique was later applied to human iPSCs, with the aim to produce a more patient-specific and translational platform. 189 Despite the ability of iPSCs to give rise to all cell types of the body, as opposed to more restricted multipotent NSCs employed by Stewart et al , ES induced cells of the three germ layers from the iPSCs but with the addition of neurobasal media, a clear bias toward neural induction was recorded, with neuronal over glial fate determination. 45,189 …”

Biomedical Implants with Charge‐Transfer Monitoring and Regulating Abilities

“…[138] In a recent study, PPy containing the anionic dopant dodecylbenzenesulfonate was selected as an electrode to stimulate the human induced pluripotent stem cells (iPSCs), and the results showed that the PPy electrode presented high biocompatibility and the PPy-mediated electrical stimulation could promote differentiation of the iPSCs. [139] In another work, Rizau-Reid et al [140] improved the functionality of PEDOT:PSS in neural tissue engineering by incorporating 3,4-ethylenedioxythiophene (EDOT) oligomers, and then constructed an electroactive and biocompatible block copolymer. The neurite length and branching of neural stem cells can be enhanced on the prepared material under electrical stimulation, indicating the potential of these materials to be used to construct soft electrodes.…”