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bioRxiv · 10.1101/658997

Neuron-Glial Antigen 2 (NG2)-based Glial Induction ofHuman BMSCs: A fast & safe glial progenitor cell-based therapy for congenital myelin disorders of the central nervous system

Abstract

ABSTRACT/ SUMMARYOligodendrocytes (OLs) are the only myelinating glia in the central nervous system (CNS). In congenital myelin disorders, OL dysfunction or death results in loss of myelin. This causes progressive and irreversible impairment to motor and cognitive functions, and is amongst the most disabling neurological disorder. Neonatal engraftment by glial progenitor cells (GPCs) allows the robust myelination of congenitally dysmyelinated brain, thereby preserving brain function and quality of life of patients. However, endogenous sources of glial progenitors are hard to obtain without causing secondary injury, while use of exogenous sources such as embryonic stem cells and induced-pluripotent stem cells face considerable ethical and safety issues. To circumvent such hurdles, we asked whether NG2+ cells in the bone marrow could be a potential cell source for GPCs. We successfully generated glial progenitor cells (GPCs) from human bone marrow stromal cells (hBMSCs) from 3 donors using a 14- day induction protocol. The generated hBMSC-GPCs were highly enriched in OPC marker expression, including OLIG2, PDGFR, NG2, SOX10 and O4, and showed efficient differentiation into myelinogenic oligodendrocytes when transplanted into postnatal day 7 (P7) myelin-deficient shiverer mice. Remyelination of the shiverer mouse brain significantly extended lifespan and improved motor function. The novel induction protocol described here provides a method for fast, simple and effective glial therapy for myelin disorders, overcoming existent hurdles of cell source restriction and time frame requirement. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=153 SRC="FIGDIR/small/658997v8_ufig1.gif" ALT="Figure 1"> View larger version (35K): org.highwire.dtl.DTLVardef@104a62corg.highwire.dtl.DTLVardef@399a67org.highwire.dtl.DTLVardef@1c81ee1org.highwire.dtl.DTLVardef@16374da_HPS_FORMAT_FIGEXP M_FIG C_FIG Highlights- Human bone marrow stromal cells (BMSCs) can be programmed to myelinating glia (GPCs, glial progenitor cells), via a novel 14-day in vitro induction protocol - Transplantation of these hBM-GPCs robustly remyelinated myelin deficient shiverer mice. - hBM-GPC transplant significantly extended lifespan, increased body weight and improved motor function

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Lam, G., Shea, G. K.-H., Wu, K. L. K., Li, M. T.-S., Kwok, C. H., Wong, C. Y., Tsui, A. Y. P., Shum, D. K. Y., Chan, Y. S.. 2019-06-17. Neuron-Glial Antigen 2 (NG2)-based Glial Induction ofHuman BMSCs: A fast & safe glial progenitor cell-based therapy for congenital myelin disorders of the central nervous system. https://doi.org/10.1101/658997

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