Project description:This study identified gene expression of Side Population (SP) and Main Population (MP) cells, isolated from adult murine skeletal muscle and Bone Marrow. Five different preparations of muscle SP, muscle MP, Bone marrw SP and Bone marrow MP cells were used as replicates.
Project description:This study identified gene expression of Side Population (SP) and Main Population (MP) cells, isolated from adult murine skeletal muscle and Bone Marrow. Five different preparations of muscle SP, muscle MP, Bone marrw SP and Bone marrow MP cells were used as replicates. SUBMITTER_CITATION: Liadaki K, Kho AT, Sanoudou D, Schienda J, Flint A, Beggs AH, Kohane IS, Kunkel LM. Side population cells isolated from different tissues share transcriptome signatures and express tissue-specific markers. Exp Cell Res. 2005;303(2):360-74.
Project description:Bone regeneration involves skeletal stem/progenitor cells within periosteum and bone marrow, the formation of a fibrous callus followed by the deposition of cartilage and bone matrix to consolidate the fracture. Interactions between bone and skeletal muscle are known to play a role in bone repair but the underlying mechanisms are poorly understood. To better understand the role of skeletal muscle during bone repair, we characterized stem/progenitor cells within skeletal muscle that participate in bone repair. We show that cells originating from bone marrow, periosteum and skeletal muscle are all derived from the Prx1 embryonic lineage. We developed a mouse polytrauma model combining a non-stabilized tibial fracture and mechanical injury to adjacent skeletal muscles. In this polytrauma model, bone fracture healing is impaired. We characterized the Prx1-derived cell population within skeletal muscle in response to fracture and to polytrauma. To do so, we performed fracture and polytrauma in Prx1Cre;Rosa mTmG mice. We harvested skeletal muscle surrounding the tibia at d0 (uninjured), and surrounding the fracture site at d3 and d5 post-fracture or post-polytrauma. Following enzymatic and mechanical digestion of skeletal muscle tissue, we FACS sorted Prx1-derived GFP+ cells and sequenced them using the 10X Chromium technology.
Project description:Analysis of the transcriptome of mononuclear side population (SP) and main population (MP) cells of human fetal skeletal muscle from 12 human subjects of gestational age 14-18 weeks. Total RNA was extracted and profiled from 12 human fetal skeletal muscle side population (SP) cells and 10 corresponding human skeletal muscle main population (MP) cells.
Project description:We isolated murine fetal liver and murine adult bone marrow and FACS sorted LT-HSCs, ST-HSCs and MPPs. We used global expression analysis by microarray to compare regulated genesets in different HSC populations in fetal and adult.
Project description:Muscle stem cells, also known as satellite cells, represent the main myogenic population accounting for skeletal muscle homeostasis and regeneration. Here, using the Assay for Transposase Accessible Chromatin followed by sequencing (ATAC-seq), we investigated the epigenetic landscape of activated human and murine satellite cells. Our analysis identified a compendium of putative regulatory elements defining activated satellite cells and myoblasts, respectively.
Project description:The expression of Prx1 has been used as a marker to define the skeletal stem cells (SSC) populations found within the bone marrow and periosteum that contribute to bone regeneration. However, Prx1 expressing SSCs (Prx1-SSCs) are not restricted to the bone compartments, but are also located within the muscle and able to contribute to ectopic bone formation. Little is known however, about the mechanism(s) regulating Prx1-SSCs that reside in muscle and how they participate in bone regeneration. This study compared both the intrinsic and extrinsic factors of the periosteum and muscle derived Prx1-SSCs and analyzed their regulatory mechanisms of activation, proliferation, and skeletal differentiation. There was considerable transcriptomic heterogeneity in the Prx1-SSCs found in muscle or the periosteum however in vitro cells from both tissues show tri-lineage (adipose, cartilage and bone) differentiation. At homeostasis, periosteal derived Prx1 cells were proliferative and low levels of BMP2 were able to promote their differentiation, while the muscle derived Prx1 cells were quiescent and refractory to comparable levels of BMP2 that promoted periosteal cell differentiation. The transplantation of Prx1-SCC from muscle and periosteum into either the same site from which they were isolated, or their reciprocal sites showed that periosteal cell transplanted onto the surface of bone tissues differentiated into bone and cartilage cells but was incapable of similar differentiation when transplanted into muscle. Prx1-SSCs from the muscle showed no ability to differentiate at either site of transplantation. Both fracture and ten times the BMP2 dose was needed to promote muscle-derived cells to rapidly enter the cell cycle as well as undergo skeletal cell differentiation. This study elucidates the diversity of the Prx1-SSC population showing that cells within different tissue sites are intrinsically different. While muscle tissue must have factors that promote Prx1-SSC to remain quiescent, either bone injury or high levels of BMP2 can activate these cells to both proliferate and undergo skeletal cell differentiation. Finally, these studies raise the possibility that muscle SSCs are potential target for skeletal repair and bone diseases.
Project description:Leptin receptor (LepR)-positive cells are key components of the bone marrow hematopoietic microenvironment, and highly enrich skeletal stem and progenitor cells that maintain homeostasis of the adult skeleton. However, the heterogeneity and lineage hierarchy within this population has been elusive. Using genetic lineage tracing and single-cell RNA sequencing, we found that Lepr-Cre labels most bone marrow stromal cells and osteogenic lineage cells in adult long bones. Integrated analysis of Lepr-Cre-traced cells under homeostatic and stress conditions revealed dynamic changes of the adipogenic, osteogenic, and periosteal lineages. Importantly, we discovered a Notch3+ bone marrow sub-population that is slow-cycling and closely associated with the vasculatures, as well as key transcriptional networks promoting osteo-chondrogenic differentiation. We also identified a Sca-1+ periosteal sub-population with high clonogenic activity but limited osteo-chondrogenic potential. Together, we mapped the transcriptomic landscape of adult LepR+ stem and progenitor cells and uncovered cellular and molecular mechanisms underlying their maintenance and lineage specification.
Project description:The regenerative capacity of skeletal muscle relies on muscle stem cells (MuSCs, or satellite cells) and its niche interactions with different neighboring cells. To understand the cellular diversity within adult skeletal muscle tissue, we harvested mononuclear cells from hindlimb skeletal muscles, sorted into single cells and profiled them by single-cell RNA-seq. To further understand and compare the expression profile between MuSCs and a novel smooth-muscle/mesenchymal-like cells (SMMCs) population, we isolated the two cell types by FACS and profiled them respectively by bulk RNA-seq.