Hox genes are an evolutionary highly conserved gene family. They determine the anterior-posterior body axis in bilateral organisms and influence the developmental fate of cells. Embryonic stem cells are usually devoid...Hox genes are an evolutionary highly conserved gene family. They determine the anterior-posterior body axis in bilateral organisms and influence the developmental fate of cells. Embryonic stem cells are usually devoidof any Hox gene expression, but these transcription factors are activated in varying spatial and temporal patterns defining the development of various body regions. In the adult body, Hox genes are among others responsible for driving the differentiation of tissue stem cells towards their respective lineages in order to repair and maintain the correct function of tissues and organs. Due to their involvement in the embryonic and adult body, they have been suggested to be useable for improving stem cell differentiations in vitro and in vivo. In many studies Hox genes have been found as driving factors in stem cell differentiation towards adipogenesis, in lineages involved in bone and joint formation, mainly chondrogenesis and osteogenesis, in cardiovascular lineages including endothelial and smooth muscle cell differentiations, and in neurogenesis. As life expectancy is rising, the demand for tissue reconstruction continues to increase. Stem cells have become an increasingly popular choice for creating therapies in regenerative medicine due to their self-renewal and differentiation potential. Especially mesenchymal stem cells are used more and more frequently due to their easy handling and accessibility, combined with a low tumorgenicity and little ethical concerns. This review therefore intends to summarize to date known correlations between natural Hox gene expression patterns in body tissues and during the differentiation of various stem cells towards their respective lineages with a major focus on mesenchymal stem cell differentiations. This overview shall help to understand the complex interactions of Hox genes and differentiation processes all over the body as well as in vitro for further improvement of stem cell treatments in future regenerative medicine approaches.展开更多
Parkinson’s disease is typically characterized by the progressive loss of dopaminergic neurons in the substantia nigra pars compacta.Many studies have been performed based on the supplementation of lost dopaminergic ...Parkinson’s disease is typically characterized by the progressive loss of dopaminergic neurons in the substantia nigra pars compacta.Many studies have been performed based on the supplementation of lost dopaminergic neurons to treat Parkinson’s disease.The initial strategy for cell replacement therapy used human fetal ventral midbrain and human embryonic stem cells to treat Parkinson’s disease,which could substantially alleviate the symptoms of Parkinson’s disease in clinical practice.However,ethical issues and tumor formation were limitations of its clinical application.Induced pluripotent stem cells can be acquired without sacrificing human embryos,which eliminates the huge ethical barriers of human stem cell therapy.Another widely considered neuronal regeneration strategy is to directly reprogram fibroblasts and astrocytes into neurons,without the need for intermediate proliferation states,thus avoiding issues of immune rejection and tumor formation.Both induced pluripotent stem cells and direct reprogramming of lineage cells have shown promising results in the treatment of Parkinson’s disease.However,there are also ethical concerns and the risk of tumor formation that need to be addressed.This review highlights the current application status of cell reprogramming in the treatment of Parkinson’s disease,focusing on the use of induced pluripotent stem cells in cell replacement therapy,including preclinical animal models and progress in clinical research.The review also discusses the advancements in direct reprogramming of lineage cells in the treatment of Parkinson’s disease,as well as the controversy surrounding in vivo reprogramming.These findings suggest that cell reprogramming may hold great promise as a potential strategy for treating Parkinson’s disease.展开更多
Single-cell omics sequencingwas first achieved for the transcriptome in 2009,whichwas followed by fast development of technologies for profiling the genome,DNA methylome,3D genome architecture,chromatin accessibility,...Single-cell omics sequencingwas first achieved for the transcriptome in 2009,whichwas followed by fast development of technologies for profiling the genome,DNA methylome,3D genome architecture,chromatin accessibility,histone modifications,etc.,in an individual cell.In this review we mainly focus on the recent progress in four topics in the single-cell omics field:single-cell epigenome sequencing,single-cell genome sequencing for lineage tracing,spatially resolved single-cell transcriptomics and third-generation sequencing platform-based single-cell omics sequencing.We also discuss the potential applications and future directions of these single-cell omics sequencing technologies for different biomedical systems,especially for the human stem cell field.展开更多
In this review we evaluate evidence for three different hypotheses that explain how the corneal epithelium is maintained. The limbal epithelial stem cell(LESC)hypothesis is most widely accepted. This proposes that ste...In this review we evaluate evidence for three different hypotheses that explain how the corneal epithelium is maintained. The limbal epithelial stem cell(LESC)hypothesis is most widely accepted. This proposes that stem cells in the basal layer of the limbal epithelium, at the periphery of the cornea, maintain themselves and also produce transient(or transit) amplifying cells(TACs). TACs then move centripetally to the centre of the cornea in the basal layer of the corneal epithelium and also replenish cells in the overlying suprabasal layers. The LESCs maintain the corneal epithelium during normal homeostasis and become more active to repair significant wounds. Second, the corneal epithelial stem cell(CESC) hypothesis postulates that, during normal homeostasis, stem cells distributed throughout the basal corneal epithelium, maintain the tissue. According to this hypothesis, LESCs are present in the limbus but are only active during wound healing. We also consider a third possibility, that the corneal epithelium is maintained during normal homeostasis by proliferation of basal corneal epithelial cells without any input from stem cells. After reviewing the published evidence, we conclude that the LESC and CESC hypotheses are consistent with more of the evidence than the third hypothesis, so we do not consider this further. The LESC and CESC hypotheses each have difficulty accounting for one main type of evidence so we evaluate the two key lines of evidence that discriminate between them. Finally, we discuss how lineage-tracing experiments have begun to resolve the debate in favour of the LESC hypothesis. Nevertheless, it also seems likely that some basal corneal epithelial cells can act as long-term progenitors if limbal stem cell function is compromised. Thus, this aspect of the CESC hypothesis may have a lasting impact on our understanding of corneal epithelial maintenance, even if it is eventually shown that stem cells are restricted to the limbus as proposed by the LESC hypothesis.展开更多
In multicellular organisms,developmental history of cell divisions and functional annotation of terminal cells can be organized into a cell lineage tree(CLT).The reconstruction of the CLT has long been a major goal in...In multicellular organisms,developmental history of cell divisions and functional annotation of terminal cells can be organized into a cell lineage tree(CLT).The reconstruction of the CLT has long been a major goal in developmental biology and other related fields.Recent technological advancements,especially those in editable genomic barcodes and single-cell high-throughput sequencing,have sparked a new wave of experimental methods for reconstructing CLTs.Here we review the existing experimental approaches to the reconstruction of CLT,which are broadly categorized as either image-based or DNA barcode-based methods.In addition,we present a summary of the related literature based on the biological insight pro-vided by the obtained CLTs.Moreover,we discuss the challenges that will arise as more and better CLT data become available in the near future.Genomic barcoding-based CLT reconstructions and analyses,due to their wide applicability and high scalability,offer the potential for novel biological discoveries,especially those related to general and systemic properties of the developmental process.展开更多
Ex vivo-expanded mesenchymal stem cells(MSCs)have been demonstrated to be a heterogeneous mixture of cells exhibiting varying proliferative,multipotential,and immunomodulatory capacities.However,the exact characterist...Ex vivo-expanded mesenchymal stem cells(MSCs)have been demonstrated to be a heterogeneous mixture of cells exhibiting varying proliferative,multipotential,and immunomodulatory capacities.However,the exact characteristics of MSCs remain largely unknown.By singlecell 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 prechondrocytes.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 suppress 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 heterogeneous cellular composition,allowing for more specific and effective MSC application through the purification of their functional subpopulations.展开更多
The lung is the most critical organ of the respiratory system supporting gas exchange.Constant interaction with the external environment makes the lung vulnerable to injury.Thus,a deeper understanding of cellular and ...The lung is the most critical organ of the respiratory system supporting gas exchange.Constant interaction with the external environment makes the lung vulnerable to injury.Thus,a deeper understanding of cellular and molecular processes underlying lung development programs and evaluation of progenitor status within the lung is an essential part of lung regenerative medicine.In this review,we aim to discuss the current understanding of lung development process and regenerative capability.We highlight the advances brought by multi-omics approaches,single-cell transcriptome,in particular,that can help us further dissect the cellular player and molecular signaling underlying those processes.展开更多
The intestinal epithelium is one of the most rapidly renewing tissues,which is fueled by stem cells at the base of the crypts.Strategies of genetic lineage tracing and organoids,which capture major features of origina...The intestinal epithelium is one of the most rapidly renewing tissues,which is fueled by stem cells at the base of the crypts.Strategies of genetic lineage tracing and organoids,which capture major features of original tissues,are powerful avenues for exploring the biology of intestinal stem cells in vivo and in vitro,respectively.The combination of intestinal organoideculturing system and genetic modification approaches provides an attractive platform to uncover the mechanism of colorectal cancer and genetic disorders in the human minigut.Here,we will provide a comprehensive overview of studies on intestinal epithelium and intestinal stem cells.We will also review the applications of organoids and genetic markers in intestinal research studies.Furthermore,we will discuss the advantages and drawbacks of organoids as disease models compared with mice models and cell lines.展开更多
Necroptosis is a tightly regulated form of necrosis that requires the activation of receptor-interacting protein(RIP)kinases RIPK1 and RIPK3,as well as the RIPK3 substrate mixed lineage kinase domain-like protein(MLKL...Necroptosis is a tightly regulated form of necrosis that requires the activation of receptor-interacting protein(RIP)kinases RIPK1 and RIPK3,as well as the RIPK3 substrate mixed lineage kinase domain-like protein(MLKL).Because of membrane rupture,necroptotic cells release damage-associated molecular patterns(DAMPs)that evoke immune responses.Necroptosis is emerging as an important cellular response in the modulation of cancer initiation,progression,and metastasis.Necroptosis of cancer cells is considered to be an immunogenic cell death capable of activating anti-tumor immunity.Necroptosis also participates in the promotion of myeloid cell-induced adaptive immune suppression and thus contributes to oncogenesis.In addition,necroptosis of endothelial cells and tumor cells is conducive to tumor metastasis.In this review,we summarize the current knowledge of the complex role of necroptosis in cancer and discuss the potential of targeting necroptosis components for cancer therapies.展开更多
基金BMBF,Adi Pa D,1720X06,BMBF,FHprof Unt,FKZ:03FH012PB2FH-Extra,"Europischer Fonds für regionale Entwicklung","Europa-Investition in unsere Zukunft",FKZ:z1112fh012EFRE co-financed NRW Ziel 2:"Regionale Wettbewerbsfhigkeit und Beschftigung",DAAD,PPP Vigoni,FKZ:314-vigoni-dr and FKZ:54669218 for Edda Tobiasch
文摘Hox genes are an evolutionary highly conserved gene family. They determine the anterior-posterior body axis in bilateral organisms and influence the developmental fate of cells. Embryonic stem cells are usually devoidof any Hox gene expression, but these transcription factors are activated in varying spatial and temporal patterns defining the development of various body regions. In the adult body, Hox genes are among others responsible for driving the differentiation of tissue stem cells towards their respective lineages in order to repair and maintain the correct function of tissues and organs. Due to their involvement in the embryonic and adult body, they have been suggested to be useable for improving stem cell differentiations in vitro and in vivo. In many studies Hox genes have been found as driving factors in stem cell differentiation towards adipogenesis, in lineages involved in bone and joint formation, mainly chondrogenesis and osteogenesis, in cardiovascular lineages including endothelial and smooth muscle cell differentiations, and in neurogenesis. As life expectancy is rising, the demand for tissue reconstruction continues to increase. Stem cells have become an increasingly popular choice for creating therapies in regenerative medicine due to their self-renewal and differentiation potential. Especially mesenchymal stem cells are used more and more frequently due to their easy handling and accessibility, combined with a low tumorgenicity and little ethical concerns. This review therefore intends to summarize to date known correlations between natural Hox gene expression patterns in body tissues and during the differentiation of various stem cells towards their respective lineages with a major focus on mesenchymal stem cell differentiations. This overview shall help to understand the complex interactions of Hox genes and differentiation processes all over the body as well as in vitro for further improvement of stem cell treatments in future regenerative medicine approaches.
基金supported by the National Natural Science Foundation of China,No.31960120Yunnan Science and Technology Talent and Platform Plan,No.202105AC160041(both to ZW).
文摘Parkinson’s disease is typically characterized by the progressive loss of dopaminergic neurons in the substantia nigra pars compacta.Many studies have been performed based on the supplementation of lost dopaminergic neurons to treat Parkinson’s disease.The initial strategy for cell replacement therapy used human fetal ventral midbrain and human embryonic stem cells to treat Parkinson’s disease,which could substantially alleviate the symptoms of Parkinson’s disease in clinical practice.However,ethical issues and tumor formation were limitations of its clinical application.Induced pluripotent stem cells can be acquired without sacrificing human embryos,which eliminates the huge ethical barriers of human stem cell therapy.Another widely considered neuronal regeneration strategy is to directly reprogram fibroblasts and astrocytes into neurons,without the need for intermediate proliferation states,thus avoiding issues of immune rejection and tumor formation.Both induced pluripotent stem cells and direct reprogramming of lineage cells have shown promising results in the treatment of Parkinson’s disease.However,there are also ethical concerns and the risk of tumor formation that need to be addressed.This review highlights the current application status of cell reprogramming in the treatment of Parkinson’s disease,focusing on the use of induced pluripotent stem cells in cell replacement therapy,including preclinical animal models and progress in clinical research.The review also discusses the advancements in direct reprogramming of lineage cells in the treatment of Parkinson’s disease,as well as the controversy surrounding in vivo reprogramming.These findings suggest that cell reprogramming may hold great promise as a potential strategy for treating Parkinson’s disease.
基金This work was supported by the National Key Research and Development Program of China(Grant No.2018YFA0107601).
文摘Single-cell omics sequencingwas first achieved for the transcriptome in 2009,whichwas followed by fast development of technologies for profiling the genome,DNA methylome,3D genome architecture,chromatin accessibility,histone modifications,etc.,in an individual cell.In this review we mainly focus on the recent progress in four topics in the single-cell omics field:single-cell epigenome sequencing,single-cell genome sequencing for lineage tracing,spatially resolved single-cell transcriptomics and third-generation sequencing platform-based single-cell omics sequencing.We also discuss the potential applications and future directions of these single-cell omics sequencing technologies for different biomedical systems,especially for the human stem cell field.
基金Supported by Grants from the Wellcome Trust,No.088876/Z/09/Zthe UK Biotechnology and Biological Sciences Research Council,No.BB/J015172/1 and No.BB/J015237/1
文摘In this review we evaluate evidence for three different hypotheses that explain how the corneal epithelium is maintained. The limbal epithelial stem cell(LESC)hypothesis is most widely accepted. This proposes that stem cells in the basal layer of the limbal epithelium, at the periphery of the cornea, maintain themselves and also produce transient(or transit) amplifying cells(TACs). TACs then move centripetally to the centre of the cornea in the basal layer of the corneal epithelium and also replenish cells in the overlying suprabasal layers. The LESCs maintain the corneal epithelium during normal homeostasis and become more active to repair significant wounds. Second, the corneal epithelial stem cell(CESC) hypothesis postulates that, during normal homeostasis, stem cells distributed throughout the basal corneal epithelium, maintain the tissue. According to this hypothesis, LESCs are present in the limbus but are only active during wound healing. We also consider a third possibility, that the corneal epithelium is maintained during normal homeostasis by proliferation of basal corneal epithelial cells without any input from stem cells. After reviewing the published evidence, we conclude that the LESC and CESC hypotheses are consistent with more of the evidence than the third hypothesis, so we do not consider this further. The LESC and CESC hypotheses each have difficulty accounting for one main type of evidence so we evaluate the two key lines of evidence that discriminate between them. Finally, we discuss how lineage-tracing experiments have begun to resolve the debate in favour of the LESC hypothesis. Nevertheless, it also seems likely that some basal corneal epithelial cells can act as long-term progenitors if limbal stem cell function is compromised. Thus, this aspect of the CESC hypothesis may have a lasting impact on our understanding of corneal epithelial maintenance, even if it is eventually shown that stem cells are restricted to the limbus as proposed by the LESC hypothesis.
基金supported by the National Key Research and Development Program of China(2021YFF1200904,2021YFA1302500 to J.-R.Y.)the National Natural Science Foundation of China(32122022,31871320 to J.-R.Y.)by Science and Technology Planning Project of Guangdong Province,China(2014A030304053 to X.Z.).
文摘In multicellular organisms,developmental history of cell divisions and functional annotation of terminal cells can be organized into a cell lineage tree(CLT).The reconstruction of the CLT has long been a major goal in developmental biology and other related fields.Recent technological advancements,especially those in editable genomic barcodes and single-cell high-throughput sequencing,have sparked a new wave of experimental methods for reconstructing CLTs.Here we review the existing experimental approaches to the reconstruction of CLT,which are broadly categorized as either image-based or DNA barcode-based methods.In addition,we present a summary of the related literature based on the biological insight pro-vided by the obtained CLTs.Moreover,we discuss the challenges that will arise as more and better CLT data become available in the near future.Genomic barcoding-based CLT reconstructions and analyses,due to their wide applicability and high scalability,offer the potential for novel biological discoveries,especially those related to general and systemic properties of the developmental process.
基金supported by the National Natural Science Foundation of China(Grant Nos.81890992 to QFW,81770109 and 81970108 to YL)the Youth Innovation Promotion Association of Chinese Academy of Sciences,China(Grant No.2017142 to YL)。
文摘Ex vivo-expanded mesenchymal stem cells(MSCs)have been demonstrated to be a heterogeneous mixture of cells exhibiting varying proliferative,multipotential,and immunomodulatory capacities.However,the exact characteristics of MSCs remain largely unknown.By singlecell 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 prechondrocytes.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 suppress 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 heterogeneous cellular composition,allowing for more specific and effective MSC application through the purification of their functional subpopulations.
基金supported by Science and Technology Planning Project of Guangdong Province(2020B1212060052)supported by Guangdong Basic and Applied Basic Research Foundation(2019A1515110985).
文摘The lung is the most critical organ of the respiratory system supporting gas exchange.Constant interaction with the external environment makes the lung vulnerable to injury.Thus,a deeper understanding of cellular and molecular processes underlying lung development programs and evaluation of progenitor status within the lung is an essential part of lung regenerative medicine.In this review,we aim to discuss the current understanding of lung development process and regenerative capability.We highlight the advances brought by multi-omics approaches,single-cell transcriptome,in particular,that can help us further dissect the cellular player and molecular signaling underlying those processes.
基金supported by the National Key Research and Development Program of China(2017YFA0103603 to X.W.)supported by Beijing Natural Science Foundation(Z190016 to X.W.)。
文摘The intestinal epithelium is one of the most rapidly renewing tissues,which is fueled by stem cells at the base of the crypts.Strategies of genetic lineage tracing and organoids,which capture major features of original tissues,are powerful avenues for exploring the biology of intestinal stem cells in vivo and in vitro,respectively.The combination of intestinal organoideculturing system and genetic modification approaches provides an attractive platform to uncover the mechanism of colorectal cancer and genetic disorders in the human minigut.Here,we will provide a comprehensive overview of studies on intestinal epithelium and intestinal stem cells.We will also review the applications of organoids and genetic markers in intestinal research studies.Furthermore,we will discuss the advantages and drawbacks of organoids as disease models compared with mice models and cell lines.
基金supported by the National Natural Science Foundation of China(Nos.31671436,31600133,31771533,and 31830051)the Priority Academic Program Development of Jiangsu Higher Education Institutions,the Natural Science Foundation of Jiangsu Province(No.BK20160314)+1 种基金the Fok Ying Tung Education Foundation for Young Teachers(No.151020)the Non-profit Central Research Institute Fund of Chinese Academy of Medical Sciences(Nos.2017NL31002 and 2017NL31004)
文摘Necroptosis is a tightly regulated form of necrosis that requires the activation of receptor-interacting protein(RIP)kinases RIPK1 and RIPK3,as well as the RIPK3 substrate mixed lineage kinase domain-like protein(MLKL).Because of membrane rupture,necroptotic cells release damage-associated molecular patterns(DAMPs)that evoke immune responses.Necroptosis is emerging as an important cellular response in the modulation of cancer initiation,progression,and metastasis.Necroptosis of cancer cells is considered to be an immunogenic cell death capable of activating anti-tumor immunity.Necroptosis also participates in the promotion of myeloid cell-induced adaptive immune suppression and thus contributes to oncogenesis.In addition,necroptosis of endothelial cells and tumor cells is conducive to tumor metastasis.In this review,we summarize the current knowledge of the complex role of necroptosis in cancer and discuss the potential of targeting necroptosis components for cancer therapies.
