Generation of phenotypically stable and functionally mature human bone marrow MSCs derived Schwann cells via the induction of human iPSCs-derived sensory neurons

Background Phenotypically unstable Schwann cell-like cells (SCLCs), derived from mesenchymal stem cells (MSCs) require intercellular contact-mediated cues for Schwann cell (SCs)-fate commitment. Although rat dorsal root ganglion (DRG) neurons provide contact-mediated signals for the conversion of SCLCs into fate-committed SCs, the use of animal cells is clinically unacceptable. To overcome this problem, we previously acquired human induced pluripotent stem cell-derived sensory neurons (hiPSC-dSNs) as surrogates of rat DRG neurons that committed rat bone marrow SCLC to the SC fate. In this study, we explored whether hiPSC-dSNs could mimic rat DRG neurons effects to obtain fate-committed SCs from hBMSC-derived SCLC. Methods hiPSCs were induced into hiPSC-dSNs using a specific chemical small molecules combination. hBMSCs were induced into hBMSC-derived SCLCs in specific culture medium and then co-cultured with hiPSC-dSNs to generate SCs. The identity of hBMSC-derived SCs (hBMSC-dSCs) were examine by immunofluorescence, western bolt, electronic microscopy, and RNA-seq. Immunofluorescence was also used to detect the myelination capacity. Enzyme-Linked Immunosorbant Assay and neurite outgrowth analysis was used to test the neurotrophic factors secretion. Results The hBMSC-dSCs exhibited bi-/tri-polar morphology of SCs and maintained the expression of the SC markers S100, p75NTR, p0, GFAP, and Sox10, even after withdrawing the glia-inducing factors or hiPSC-dSNs. Electronic microscopy and RNA-seq analysis provided evidence that hBMSC-dSCs were similar to the original human SCs in terms of their function and a variety of characteristics. Furthermore, these cells formed MBP-positive segments and secreted neurotrophic factors to facilitate the neurite outgrowth of Neuro2A. Conclusions These results demonstrated that phenotypically stable and functionally mature hBMSC-dSCs were generated efficiently via the co-culture of hiPSC-dSNs and hBMSC-derived SCLCs. Our findings may provide a promising protocol through which stable and fully developed hBMSC-dSCs can be used for transplantation to regenerate myelin sheath.