AUTHOR=Vellosillo Lara , Pascual-Guerra Jorge , Muñoz Maria Paz , Rodríguez-Navarro José Antonio , González-Nieto Daniel , Barrio Luis Carlos , Lobo Maria del Val Toledo , Paíno Carlos Luis 

TITLE=Oligodendroglia Generated From Adult Rat Adipose Tissue by Direct Cell Conversion

JOURNAL=Frontiers in Cell and Developmental Biology

VOLUME=10

YEAR=2022

URL=https://www.frontiersin.org/journals/cell-and-developmental-biology/articles/10.3389/fcell.2022.741499

DOI=10.3389/fcell.2022.741499

ISSN=2296-634X

ABSTRACT=<p>Obtaining oligodendroglial cells from dispensable tissues would be of great interest for autologous or immunocompatible cell replacement therapy in demyelinating diseases, as well as for studying myelin-related pathologies or testing therapeutic approaches in culture. We evaluated the feasibility of generating oligodendrocyte precursor cells (OPCs) from adult rat adipose tissue by expressing genes encoding transcription factors involved in oligodendroglial development. Adipose-derived mesenchymal cells were lentivirally transduced with tetracycline-inducible <italic>Sox10</italic>, <italic>Olig2</italic>, <italic>Zfp536</italic>, and/or <italic>Nkx6.1</italic> transgenes. Immunostaining with the OPC-specific O4 monoclonal antibody was used to mark oligodendroglial induction. O4- and myelin-associated glycoprotein (MAG)-positive cells emerged after 3 weeks when using the <italic>Sox10</italic> + <italic>Olig2</italic> + <italic>Zfp536</italic> combination, followed in the ensuing weeks by GFAP-, O1 antigen-, p75NTR (low-affinity NGF receptor)-, and myelin proteins-positive cells. The O4<sup>+</sup> cell population progressively expanded, eventually constituting more than 70% of cells in culture by 5 months. <italic>Sox10</italic> transgene expression was essential for generating O4<sup>+</sup> cells but was insufficient for inducing a full oligodendroglial phenotype. Converted cells required continuous transgene expression to maintain their glial phenotype. Some vestigial characteristics of mesenchymal cells were maintained after conversion. Growth factor withdrawal and triiodothyronine (T<sub>3</sub>) supplementation generated mature oligodendroglial phenotypes, while FBS supplementation produced GFAP<sup>+</sup>- and p75NTR<sup>+</sup>-rich cultures. Converted cells also showed functional characteristics of neural-derived OPCs, such as the expression of AMPA, NMDA, kainate, and dopaminergic receptors, as well as similar metabolic responses to differentiation-inducing drugs. When co-cultured with rat dorsal root ganglion neurons, the converted cells differentiated and ensheathed multiple axons. We propose that functional oligodendroglia can be efficiently generated from adult rat mesenchymal cells by direct phenotypic conversion.</p>