ERBB3 and NGFR mark distinct skeletal muscle progenitor cells in human development enabling enrichment and maturation of hPSC muscle
Ontology highlight
ABSTRACT: Abstract: Human pluripotent stem cells (hPSCs) can be directed to differentiate into skeletal muscle progenitor cells (SMPCs). However, the myogenic potential of hPSC-SMPCs compared to human fetal or adult satellite cells (Scs) remains unclear. This study demonstrates hPSC-SMPCs derived by commonly used protocols are functionally less mature than freshly-isolated human fetal or adult Scs. We utilized RNA-SEQ of human fetal Scs to identify differentially expressed genes including NGFR, ERBB3, which enriched for MYOD+ or PAX7+ cells. Furthermore, inhibition of TGFβ (TGFβi) improved hPSC-muscle maturation in three independent lines as measured by TEM and expression of myosins. Engraftment of CRISPR/Cas9-corrected Duchenne Muscular Dystrophy (DMD) hiPSC-SMPC subpopulations treated with TGFβi in vivo, increased dystrophin-positive fibers to levels of engrafted cultured fetal Scs in mdx mouse models of DMD. This work provides the first characterization of the developmental status of hPSC-SMPCs and identifies candidates to enable robust myogenic activity in vitro and in vivo.
Project description:The developmental trajectory of human skeletal myogenesis and the transition between progenitor and stem cell states are unclear. To address this, we employed single cell RNA-sequencing to profile human skeletal muscle tissues from embryonic, fetal and postnatal stages. In silico, we identified myogenic as well as other cell types and constructed a “roadmap” of human skeletal muscle ontogeny across development. In a similar fashion, we also profiled the heterogeneous cell cultures generated from multiple human pluripotent stem cell (hPSC) myogenic differentiation protocols, and mapped hPSC-derived myogenic progenitors to an embryonic-to-fetal transition period. Additionally, we found differentially enriched biological processes and discovered co-regulated gene networks and transcription factors present at distinct myogenic stages. In summary, this work serves as a resource for advancing our knowledge of human myogenesis. It also provides a tool for better characterization and understanding of hPSC-derived myogenic progenitors for translational applications in skeletal muscle based regenerative medicine.
Project description:To better characterize the transcriptomic profile of hPSC-derived SMPCS, we performed a comparative analysis on the gene signature of FACS-enriched human embryonic (week 9-10), fetal (week 16-20), and hPSC SMPCs and adult SCs using bulk RNA seq.
Project description:Duchenne Muscular Dystrophy (DMD) is a devastating genetic disease leading to degeneration of skeletal muscles and premature death. How dystrophin absence leads to muscle wasting remains unclear. Here, we describe an optimized protocol to differentiate human induced Pluripotent Stem Cells (iPSC) to a late myogenic stage. This allows to recapitulate classical DMD phenotypes (mislocalization of proteins of the Dystrophin glycoprotein associated complex (DGC), increased fusion, myofiber branching, force contraction defects and calcium hyperactivation) in isogenic DMD-mutant iPSC lines in vitro. Treatment of the myogenic cultures with prednisolone (the standard of care for DMD) can dramatically rescue force contraction, fusion and branching defects in DMD iPSC lines. This argues that prednisolone acts directly on myofibers, challenging the largely prevalent view that its beneficial effects are due to anti-inflammatory properties. Our work introduces a new human in vitro model to study the onset of DMD pathology and test novel therapeutic approaches.
Project description:In Duchenne Muscular Dystrophy (DMD), the absence of the subsarcolemmal dystrophin protein leads to repeated myofiber damages inducing cycles of muscle regeneration that is driven by muscle stem cells (MuSCs). With time, MuSC regenerative capacities are overwhelmed, leading to fibrosis and muscle atrophy. Whether MuSCs from DMD muscle have intrinsic alterations or are primed by their degenerative/regenerative environment is still debated. We investigated cell behavior and gene expression in human using MuSCs derived from DMD or healthy muscles. We found that proliferation, differentiation and fusion were not altered in DMD-MuSCs, but with time, they lost the expression of the myogenic marker CD56 twice as fast as healthy MuSCs. The rapid drift towards a fibroblast-like cell identity was observed at the clonal level, and resulted from the altered expression of epigenetic enzymes required to maintain the myogenic cell fate. Indeed, the reexpression of CBX3, SMC3, H2AFV and H3F3B prevented the MuSC identity drift. Amongst the epigenetic changes, a closing of chromatin at the gene encoding the transcription factor MEF2B caused a down-regulation of its expression and a loss of the myogenic fate. Thus, MEF2B is a key mediator of the myogenic identity in human MuSCs, that is altered in DMD pathology.
Project description:Schwann cells (SCs) are an absolute prerequisite for development of effective treatment of myelin disorders and nerve injuries. However, human sources of functional, myelinating SCs are extremely limited. Here, we have developed a novel, efficient strategy for producing directly an unlimited supply of functional human SCs via successful derivation of expandable Schwann cell precursors (SCPs) from human pluripotent stem cells (hPSCs) (hPSC-SCPs). Functional and molecular characteristics of SCs from hPSC-SCPs (hPSC-SCP-SCs) appeared to be similar to those of authentic Schwann cells. As a novel therapeutic target, transplanted hPSC-SCP-SCs effectively promoted axonal regeneration through directly myelinating regenerated-axons in sciatic nerve injured mice. Here, we present hPSC-SCPs and hPSC-SCP-SCs as an outstanding resource to use for investigating human Schwann cell pathology and biology and for translational approaches to PNS and CNS repair and regeneration.
Project description:Human pluripotent stem cells (hPSCs) can be directed to differentiate into skeletal muscle progenitor cells (SMPCs). However, the myogenicity of hPSC-SMPCs relative to human fetal or adult satellite cells remains unclear. We observed that hPSC-SMPCs derived by directed differentiation are less functional in vitro and in vivo compared to human satellite cells. Using RNA sequencing, we found that the cell surface receptors ERBB3 and NGFR demarcate myogenic populations, including PAX7 progenitors in human fetal development and hPSC-SMPCs. We demonstrated that hPSC skeletal muscle is immature, but inhibition of transforming growth factor-β signalling during differentiation improved fusion efficiency, ultrastructural organization and the expression of adult myosins. This enrichment and maturation strategy restored dystrophin in hundreds of dystrophin-deficient myofibres after engraftment of CRISPR-Cas9-corrected Duchenne muscular dystrophy human induced pluripotent stem cell-SMPCs. The work provides an in-depth characterization of human myogenesis, and identifies candidates that improve the in vivo myogenic potential of hPSC-SMPCs to levels that are equal to directly isolated human fetal muscle cells.
Project description:In Duchenne Muscular Dystrophy (DMD), the absence of the subsarcolemmal dystrophin protein leads to repeated myofiber damages inducing cycles of muscle regeneration that is driven by muscle stem cells (MuSCs). With time, MuSC regenerative capacities are overwhelmed, leading to fibrosis and muscle atrophy. Whether MuSCs from DMD muscle have intrinsic alterations or are primed by their degenerative/regenerative environment is still debated. We investigated gene expression in human using primary MuSCs derived from DMD or healthy muscles. Cells were isolated from the muscle and bulk expanded then purified as CD56positive cells (CD56 is a myogenic marker that characterizes the myogenic nature of the cells). Human MuSCs loose the expression of the CD56 with time. We analyzed gene expression by CD56positive and CD56negative cells originating from the same initial CD56positive MuSC population.
Project description:Skeletal muscle stem cells, or satellite cells (SCs), are essential to regenerate and maintain muscle. Quiescent SCs reside in an asymmetric niche between the basal lamina and myofiber membrane. To repair muscle, SCs activate, proliferate, and differentiate, fusing to repair myofibers or reacquiring quiescence to replenish the SC niche. Little is known about when SCs reacquire quiescence during regeneration or the cellular processes that direct SC fate decisions and progression through myogenesis. Single cell sequencing of myogenic cells in regenerating muscle identifies SCs reacquiring quiescence and reveals that non-cell autonomous signaling networks influence SC fate decisions during regeneration. Single cell RNA-sequencing of regenerating skeletal muscle reveals that RBP expression, including numerous neuromuscular disease-associated RBPs, is temporally regulated in skeletal muscle stem cells and correlates to stages of myogenic differentiation. By combining machine learning with RBP engagement scoring, we discover that the neuromuscular disease associated RBP Hnrnpa2b1 is a differentiation-specifying regulator of myogenesis controlling myogenic cell fate transitions during terminal differentiation.
Project description:Satellite cells (SCs), the skeletal muscle stem cells, display functional heterogeneity linked to their regenerative potential. Dramatic changes in their behaviour are also associated to muscle wasting diseases. Therefore, understanding the mechanisms controlling satellite cell heterogeneous behaviour during muscle regeneration and diseases has become increasingly important for regenerative medicine. Here, we show that miR-106bis expressed in Myf5- quiescent SCs and downregulated during SC activation and muscle regeneration. In vitro and in vivo studies to show that miR106b inhibition enhances the regenerative capability of murine and human SCs by increasing myogenic precursors. miR106b is increased in dystrophic mice and intramuscular injection of antimiR enhances muscle regeneration accompanied by significant functional recovery. miR-106b is also elevated in human dystrophic SCs and its inhibition improves intrinsic proliferative defects, increasing their myogenic differentiation potential. Therefore, this study identifies miR-106b as compelling candidate to consider for potential clinical studies.
Project description:Differentiation of pluripotent stem cells (PSCs) is a promising approach to obtaining large quantities of skeletal myogenic progenitors for disease modeling and cell-based therapy. However, generating skeletal myogenic cells with high regenerative potential is still challenging. We recently reported that skeletal myogenic progenitors generated from mouse PSC-derived teratomas possess robust regenerative potency. We have also found that teratomas derived from human PSCs contain a skeletal myogenic population. Here, we showed that these human PSC-derived skeletal myogenic progenitors had exceptional engraftability. A combination of cell surface markers, CD82, ERBB3, and NGFR enabled efficient purification of skeletal myogenic progenitors. These cells expressed PAX7 and were able to differentiate into MHC+ multinucleated myotubes. We further discovered that these cells are expandable in vitro. Upon transplantation, the expanded cells formed new dystrophin+ fibers that reconstituted almost ¾ of the total muscle volume, and repopulated the muscle stem cell pool. Our study, therefore, demonstrates the possibility of producing large quantities of engraftable skeletal myogenic cells from human PSCs.