1.Single-cell Transcriptomic Analysis Reveals the Cellular Heterogeneity of Mesenchymal Stem Cells
Zhang CHEN ; Han XUESHUAI ; Liu JINGKUN ; Chen LEI ; Lei YING ; Chen KUNYING ; Si JIA ; Wang TIAN-YI ; Zhou HUI ; Zhao XIAOYUN ; Zhang XIAOHUI ; An YIHUA ; Li YUEYING ; Wang QIAN-FEI
Genomics, Proteomics & Bioinformatics 2022;20(1):70-86
Ex vivo-expanded mesenchymal stem cells(MSCs)have been demonstrated to be a heterogeneous mixture of cells exhibiting varying proliferative,multipotential,and immunomodu-latory capacities.However,the exact characteristics of MSCs remain largely unknown.By single-cell RNA sequencing of 61,296 MSCs derived from bone marrow and Wharton's jelly,we revealed five distinct subpopulations.The developmental trajectory of these five MSC subpopulations was mapped,revealing a differentiation path from stem-like active proliferative cells(APCs)to multipotent progenitor cells,followed by branching into two paths:1)unipotent preadipocytes or 2)bipotent prechondro-osteoblasts that were subsequently differentiated into unipotent prechondro-cytes.The stem-like APCs,expressing the perivascular mesodermal progenitor markers CSPG4/MCAM/NES,uniquely exhibited strong proliferation and stemness signatures.Remarkably,the prechondrocyte subpopulation specifically expressed immunomodulatory genes and was able to sup-press activated CD3+T cell proliferation in vitro,supporting the role of this population in immunoregulation.In summary,our analysis mapped the heterogeneous subpopulations of MSCs and identified two subpopulations with potential functions in self-renewal and immunoregulation.Our findings advance the definition of MSCs by identifying the specific functions of their heteroge-neous cellular composition,allowing for more specific and effective MSC application through the purification of their functional subpopulations.