Black rockfish(Sebastes schlegeli) is an important species for culture; however, its reproductive characteristics have not been fully documented. In this study, we investigated the morphology and developmental process...Black rockfish(Sebastes schlegeli) is an important species for culture; however, its reproductive characteristics have not been fully documented. In this study, we investigated the morphology and developmental process of germ cells in this ovoviviparous rockfish in reproductive season(October 2011–November 2012) with histological methods. We found that the gonad of mature fish showed notable seasonal changes in developmental characteristics and morphological structure. The sperm cells matured during a period lasting from October to December, significantly earlier than the oocytes did. A large number of spermatozoa and other cells occurred in testis at different developmental stages. Vitellogenesis in oocytes began in October, and gestation appeared in April next year. Spermatophores were discovered for the first time in Sebastes, which assembled in testis, main sperm duct, oviduct and genital tract, as well as ovarian cavity in October and April. These organs may serve either as production or hiding places for spermatophores and spermatozoa which were stored and transported in form of spermatophores. Testicular degeneration started from the distal part of testis in April, with spermatophores assembled in degenerating testis and waiting for transportation. The copulation probably lasted for a long period, during which the spermatozoa were discharged in batches as spermatophores. These spermatophores were coated with sticky materials secreted from the interstitial areas of testis and the main sperm duct, then transported into ovary.展开更多
The mitogen-activated protein kinase（MAPK）pathways are a group of conserved intracellular signalling pathways present in most cells including neurons and glia.These pathways respond to a variety of stimuli including...The mitogen-activated protein kinase（MAPK）pathways are a group of conserved intracellular signalling pathways present in most cells including neurons and glia.These pathways respond to a variety of stimuli including growth factors,cytokines and oxidative stress to generate appropriate cellular responses such as modulation of gene expression,cell proliferation,differentiation and survival as well as the stress response（Korhonen and Moilanen,2014）.展开更多
In this project,we aim to elucidate the molecular mechanism controlling initiation and elongation of tetraploid Gossypium hirsutum fiber cells by setting up a high throughput custom-designed
During the last two decades our understanding of human B cell differentiation has developed considerably. Our understanding of the human B cell compartment has advanced from a point where essentially all assays were b...During the last two decades our understanding of human B cell differentiation has developed considerably. Our understanding of the human B cell compartment has advanced from a point where essentially all assays were based on the presence or not of class-switched antibodies to a level where a substantial diversity is appreciated among the cells involved. Several consecutive transitional stages that newly formed IgM expressing B cells go through after they leave the bone marrow, but before they are fully mature, have been described, and a significant complexity is also acknowledged within the IgM expressing and class-switched memory B cell compartments. It is possible to isolate plasma blasts in blood to follow the formation of plasma cells during immune responses, and the importance and uniqueness of the mucosal IgA system is now much more appreciated. Current data suggest the presence of at least one lineage of human innate-like B cells akin to B 1 and/or marginal zone B cells in mice. In addition, regu- latory B cells with the ability to produce IL-10 have been identified. Clinically, B cell depletion therapy is used for a broad range of conditions. The ability to define different human B cell subtypes using flow cytometry has therefore started to come into clinical use, but as our understanding of human B cell development further progresses, B cell subtype analysis will be of increasing importance in diagnosis, to measure the effect of immune therapy and to understand the underlying causes for diseases. In this review the diversity of human B cells will be discussed, with special focus on current data regarding their phenotypes and functions.展开更多
The process of B cell development in the bone marrow occurs by the stepwise rearrangements of the V,D,and J segments of the Ig H and L chain gene loci.During early B cell genesis,productive IgH chain gene rearrangemen...The process of B cell development in the bone marrow occurs by the stepwise rearrangements of the V,D,and J segments of the Ig H and L chain gene loci.During early B cell genesis,productive IgH chain gene rearrangement leads to assembly of the pre-B cell receptor(pre-BCR),which acts as an important checkpoint at the pro-B/preB transitional stage.The pre-BCR,transiently expressed by developing precursor B cells, comprises the Ig μH chain,surrogate light(SL)chains VpreB and λ5,as well as the signal-transducing hetero- dimer Igα/Igβ.Signaling through the pre-BCR regulates allelic exclusion at the Ig H locus,stimulates cell proliferation,and induces differentiation to small post-mitotic pre-B cells that further undergo the rearrangement of the IgL chain genes.Recent advances in elucidating the key roles of pre-BCR in B cell development have provided a better understanding of normal B lymphopoiesis and its dysregulated state leading to B cell neoplasia.Cellular & Molecular Immunology.2004;1(2):89-94.展开更多
Decabrominated diphenyl ether(BDE-209)is generally utilized in multiple polymer materials as common brominated flame retardant.BDE-209 has been listed as persistent organic pollutants(POPs),which was considered to be ...Decabrominated diphenyl ether(BDE-209)is generally utilized in multiple polymer materials as common brominated flame retardant.BDE-209 has been listed as persistent organic pollutants(POPs),which was considered to be reproductive toxin in the environment.But it still remains unclear about the effects of BDE-209 on DNA methylation and the inducedmale reproductive toxicity.Due to the extensive epigenetic regulation in germ line development,we hypothesize that BDE-209 exposure impacts the statue of DNA methylation in spermatocytes in vitro.Therefore,the mouse GC-2spd(GC-2)cells were used for the genome wide DNA methylation analysis after treated with 32μg/mL BDE-209 for 24 hr.The results showed that BDE-209 caused genomic methylation changes with 32,083 differentially methylated CpGs in GC-2 cells,including 16,164(50.38%)hypermethylated and 15,919(49.62%)hypomethylated sites.With integrated analysis ofDNAmethylation data and functional enrichment,we found that BDE-209 might affect the functional transcription in cell growth and sperm development by differential gene methylation.qRT-PCR validation demonstrated the involvement of p53-dependent DNA damage response in the GC-2 cells after BDE-209 exposure.In general,our findings indicated that BDE-209-induced genome wide methylation changes could be interrelated with reproductive dysfunction.This study might provide new insights into the mechanisms of male reproductive toxicity under the environmental exposure to BDE-209.展开更多
Methylation of adenosine base on the nitrogen-6 position （N6-methyladenosine, m^6A） is the most common and abundant modification on mRNA transcripts. This post-transcriptional modification was first described in the...Methylation of adenosine base on the nitrogen-6 position （N6-methyladenosine, m^6A） is the most common and abundant modification on mRNA transcripts. This post-transcriptional modification was first described in the 1970s in hepatoma cells （Desrosiers et al., 1974）.展开更多
The RNA editing enzyme ADAR1 has been shown to be an essential molecule for hematopoietic cell differentiation,embryonic development,and regulation of immune responses.Here,we present evidence in a T-cell-specific gen...The RNA editing enzyme ADAR1 has been shown to be an essential molecule for hematopoietic cell differentiation,embryonic development,and regulation of immune responses.Here,we present evidence in a T-cell-specific gene knockout mouse model that ADAR1 is required for early T cell development.Loss of ADAR1 led to cell death of the progenitors at the double negative stage and prevented T cell maturation in the thymus.Furthermore,ADAR1 deletion in pre-T cells preferentially affected TCRb-expressing cells causing TCRb positive cell depletion.Interruption of IFN signaling occurred in the premature T cells,indicating a role of IFN signaling in the survival of TCRb-expressing cells regulated by ADAR1.This study demonstrated an essential role for the RNA editing enzyme ADAR1 as a potential regulator for T-cell fate determination during clonal selection,which,in turn,contributes to immunologic homeostasis.展开更多
Laboratory mice have widely been used as tools for basic biological research and models for studying human diseases.With the advances of genetic engineering and conditional knockout(CKO)mice,we now understand hematopo...Laboratory mice have widely been used as tools for basic biological research and models for studying human diseases.With the advances of genetic engineering and conditional knockout(CKO)mice,we now understand hematopoiesis is a dynamic stepwise process starting from hematopoietic stem cells(HSCs)which are responsible for replenishing all blood cells.Transcriptional factors play important role in hematopoiesis.In this review we compile several studies on using genetic modified mice and humanized mice to study function of transcriptional factors in lymphopoiesis,including T lymphocyte and Natural killer(NK)cell development.Finally,we focused on the key transcriptional factor Bcl11b and its function in regulating T cell specification and commitment.展开更多
This study was designed to explore the possibility of using ascitic mouse sarcoma cell line (S180) to validate the mouse tumor cell attachment assay for developmental toxicants, and to test the inhibitory effects of v...This study was designed to explore the possibility of using ascitic mouse sarcoma cell line (S180) to validate the mouse tumor cell attachment assay for developmental toxicants, and to test the inhibitory effects of various developmental toxicants. The results showed that 2 of 3 developmental toxicants under consideration, sodium pentobarbital and ethanol, significantly inhibited S180cells attachment to Concanavalin A-coaed surfaces. Inhibition was dependent on concentration, and the IC50 (the concentration tha reduced attachment by 50% ), of these 2 chemicals was 1.2×10-3mol/L and 1 .0 mol/L, respectively. Anoher developmental toxiant, hydmiortisone, did not show inhibitory activity. Two non-developmental toxicants, sodium chloride and glycine were also tested and these did not decrease attachment rates. The main results reported here were generally sindlar to those obtained with ascitic mouse ovdrian tumor cells as a model. Therefore, this study added further evidence to the conclusion that cell specificity does not lindt attachment inhibition to Con A-coated surfaces, so S180 cell may serve as an altemative cell model, especially when other cell lines are unavailable. Furthermore, after optimal validation, it can be suggested that an S180 cell attachment assay may be a candidate for a series of assays to detect developmental toxicants.展开更多
Objective:Esophageal squamous cell carcinoma(ESCC)has high morbidity and mortality rates worldwide.Cancer stem cells(CSCs)may cause tumor initiation,metastasis,and recurrence and are also responsible for chemotherapy ...Objective:Esophageal squamous cell carcinoma(ESCC)has high morbidity and mortality rates worldwide.Cancer stem cells(CSCs)may cause tumor initiation,metastasis,and recurrence and are also responsible for chemotherapy and radiotherapy failures.Myeloid-derived suppressor cells(MDSCs),in contrast,are known to be involved in mediating immunosuppression.Here,we aimed to investigate the mechanisms of interaction of CSCs and MDSCs in the tumor microenvironment.Methods:ESCC tissues and cell lines were evaluated.Neural precursor cell expressed,developmentally downregulated 9(NEDD9)was knocked down and overexpressed by lentiviral transfection.Quantitative PCR,Western blot,immunohistochemistry,cell invasion,flow cytometry,cell sorting,multiplex chemokine profiling,and tumor growth analyses were performed.Results:Microarray analysis revealed 10 upregulated genes in esophageal CSCs.Only NEDD9 was upregulated in CSCs using the sphere-forming method.NEDD9 expression was correlated with tumor invasion(P=0.0218),differentiation(P=0.0153),and poor prognosis(P=0.0373).Additionally,NEDD9 was required to maintain the stem-like phenotype.Screening of chemokine expression in ESCC cells with NEDD9 overexpression and knockdown showed that NEDD9 regulated C-X-C motif chemokine ligand 8(CXCL8)expression via the ERK pathway.CXCL8 mediated the recruitment of MDSCs induced by NEDD9 in vitro and in vivo.MDSCs promoted the stemness of ESCC cells through NEDD9 via the Notch pathway.Conclusions:As a marker of ESCC,NEDD9 maintained the stemness of ESCC cells and regulated CXCL8 through the ERK pathway to recruit MDSCs into the tumor,suggesting NEDD9 as a therapeutic target and novel prognostic marker for ESCC.展开更多
Stem cells(SCs)with their self-renewal and pluripotent differentiation potential,show great promise for therapeutic applications to some refractory diseases such as stroke,Parkinsonism,myocardial infarction,and diabet...Stem cells(SCs)with their self-renewal and pluripotent differentiation potential,show great promise for therapeutic applications to some refractory diseases such as stroke,Parkinsonism,myocardial infarction,and diabetes.Furthermore,as seed cells in tissue engineering,SCs have been applied widely to tissue and organ regeneration.However,previous studies have shown that SCs are heterogeneous and consist of many cell subpopulations.Owing to this heterogeneity of cell states,gene expression is highly diverse between cells even within a single tissue,making precise identification and analysis of biological properties difficult,which hinders their further research and applications.Therefore,a defined understanding of the heterogeneity is a key to research of SCs.Traditional ensemble-based sequencing approaches,such as microarrays,reflect an average of expression levels across a large population,which overlook unique biological behaviors of individual cells,conceal cell-to-cell variations,and cannot understand the heterogeneity of SCs radically.The development of high throughput single cell RNA sequencing(scRNA-seq)has provided a new research tool in biology,ranging from identification of novel cell types and exploration of cell markers to the analysis of gene expression and predicating developmental trajectories.scRNA-seq has profoundly changed our understanding of a series of biological phenomena.Currently,it has been used in research of SCs in many fields,particularly for the research of heterogeneity and cell subpopulations in early embryonic development.In this review,we focus on the scRNA-seq technique and its applications to research of SCs.展开更多
Human stem cells are scalable cell populations capable of cellular differentiation.This makes them a very attractive in vitro cellular resource and in theory provides unlimited amounts of primary cells.Such an approac...Human stem cells are scalable cell populations capable of cellular differentiation.This makes them a very attractive in vitro cellular resource and in theory provides unlimited amounts of primary cells.Such an approach has the potential to improve our understanding of human biology and treating disease.In the future it may be possible to deploy novel stem cell-based approaches to treat human liver diseases.In recent years,eff icient hepatic differentiation from human stem cells has been achieved by several research groups including our own.In this review we provide an overview of the f ield and discuss the future potential and limitations of stem cell technology.展开更多
Scaffold-free techniques in the developmental tissue engineering area are designed to mimic in vivo embryonic processes with the aim of biofabricating,in vitro,tissues with more authentic properties.Cell clusters call...Scaffold-free techniques in the developmental tissue engineering area are designed to mimic in vivo embryonic processes with the aim of biofabricating,in vitro,tissues with more authentic properties.Cell clusters called spheroids are the basis for scaffold-free tissue engineering.In this review,we explore the use of spheroids from adult mesenchymal stem/stromal cells as a model in the developmental engineering area in order to mimic the developmental stages of cartilage and bone tissues.Spheroids from adult mesenchymal stromal/stem cells lineages recapitulate crucial events in bone and cartilage formation during embryogenesis,and are capable of spontaneously fusing to other spheroids,making them ideal building blocks for bone and cartilage tissue engineering.Here,we discuss data from ours and other labs on the use of adipose stromal/stem cell spheroids in chondrogenesis and osteogenesis in vitro.Overall,recent studies support the notion that spheroids are ideal"building blocks"for tissue engineering by“bottom-up”approaches,which are based on tissue assembly by advanced techniques such as three-dimensional bioprinting.Further studies on the cellular and molecular mechanisms that orchestrate spheroid fusion are now crucial to support continued development of bottom-up tissue engineering approaches such as three-dimensional bioprinting.展开更多
Smoking during pregnancy is a major source of fetal exposure to numerous harmful agents present in tobacco smoke. Lung development involves complex biochemical processes resulting in dramatic changes which continue ev...Smoking during pregnancy is a major source of fetal exposure to numerous harmful agents present in tobacco smoke. Lung development involves complex biochemical processes resulting in dramatic changes which continue even after birth. In addition to type I cells which form the blood-air barrier, type II alveolar epithelial (AE) cells have important and diverse functions related to immunological protection and stabilization of the alveolus through synthesis and secretion of the pulmonary surfactant. Apoptosis or programmed cells death is an important physiological process during lung embryogenesis and for the proper maintenance of homeostasis. Caspases are proteases that play important roles in regulating apoptosis. Caspase-3 is the key executioner caspase in the cascade of events leading to cell death by apoptosis. We explored the hypothesis that cigarette smoke extract (CSE) induces apoptosis in fetal rat lung type II AE cells by activation of caspase-3. To analyze these factors, isolated fetal rat lung type II AE cells were used. The cells were exposed to different concentrations of CSE (5%, 10% or 15%) (v/v) for 60 min. The results of the present study showed that CSE induced apoptosis in fetal rat lung type II AE cells with a significant increase (p 0.05) in caspase-3 activity and decrease in cell proliferation at CSE concentrations of 10% and 15% (v/v). These observations indicate that cigarette smoke extract induces apoptosis by activation of caspase-3 in fetal rat lung type II AE cells in a dose-dependent manner and may potentially alter the regulated development of the lung and the appearance of the surfactant-producing type II alveolar cells which are critical for the establishment of adequate gas exchange at birth.展开更多
基金supported financially by Grand Innovating Program of Agriculture Applying Technique in Shandong Province (No. 2008-109)Modern Agricultural Industry Technology System in Shandong Province and the Science and Technology Development Program of Yantai (No. 2013 ZH088)
文摘Black rockfish(Sebastes schlegeli) is an important species for culture; however, its reproductive characteristics have not been fully documented. In this study, we investigated the morphology and developmental process of germ cells in this ovoviviparous rockfish in reproductive season(October 2011–November 2012) with histological methods. We found that the gonad of mature fish showed notable seasonal changes in developmental characteristics and morphological structure. The sperm cells matured during a period lasting from October to December, significantly earlier than the oocytes did. A large number of spermatozoa and other cells occurred in testis at different developmental stages. Vitellogenesis in oocytes began in October, and gestation appeared in April next year. Spermatophores were discovered for the first time in Sebastes, which assembled in testis, main sperm duct, oviduct and genital tract, as well as ovarian cavity in October and April. These organs may serve either as production or hiding places for spermatophores and spermatozoa which were stored and transported in form of spermatophores. Testicular degeneration started from the distal part of testis in April, with spermatophores assembled in degenerating testis and waiting for transportation. The copulation probably lasted for a long period, during which the spermatozoa were discharged in batches as spermatophores. These spermatophores were coated with sticky materials secreted from the interstitial areas of testis and the main sperm duct, then transported into ovary.
基金support from Science Foundation Ireland under grant No. SFI/IA/1537
文摘The mitogen-activated protein kinase（MAPK）pathways are a group of conserved intracellular signalling pathways present in most cells including neurons and glia.These pathways respond to a variety of stimuli including growth factors,cytokines and oxidative stress to generate appropriate cellular responses such as modulation of gene expression,cell proliferation,differentiation and survival as well as the stress response（Korhonen and Moilanen,2014）.
文摘In this project,we aim to elucidate the molecular mechanism controlling initiation and elongation of tetraploid Gossypium hirsutum fiber cells by setting up a high throughput custom-designed
文摘During the last two decades our understanding of human B cell differentiation has developed considerably. Our understanding of the human B cell compartment has advanced from a point where essentially all assays were based on the presence or not of class-switched antibodies to a level where a substantial diversity is appreciated among the cells involved. Several consecutive transitional stages that newly formed IgM expressing B cells go through after they leave the bone marrow, but before they are fully mature, have been described, and a significant complexity is also acknowledged within the IgM expressing and class-switched memory B cell compartments. It is possible to isolate plasma blasts in blood to follow the formation of plasma cells during immune responses, and the importance and uniqueness of the mucosal IgA system is now much more appreciated. Current data suggest the presence of at least one lineage of human innate-like B cells akin to B 1 and/or marginal zone B cells in mice. In addition, regu- latory B cells with the ability to produce IL-10 have been identified. Clinically, B cell depletion therapy is used for a broad range of conditions. The ability to define different human B cell subtypes using flow cytometry has therefore started to come into clinical use, but as our understanding of human B cell development further progresses, B cell subtype analysis will be of increasing importance in diagnosis, to measure the effect of immune therapy and to understand the underlying causes for diseases. In this review the diversity of human B cells will be discussed, with special focus on current data regarding their phenotypes and functions.
文摘The process of B cell development in the bone marrow occurs by the stepwise rearrangements of the V,D,and J segments of the Ig H and L chain gene loci.During early B cell genesis,productive IgH chain gene rearrangement leads to assembly of the pre-B cell receptor(pre-BCR),which acts as an important checkpoint at the pro-B/preB transitional stage.The pre-BCR,transiently expressed by developing precursor B cells, comprises the Ig μH chain,surrogate light(SL)chains VpreB and λ5,as well as the signal-transducing hetero- dimer Igα/Igβ.Signaling through the pre-BCR regulates allelic exclusion at the Ig H locus,stimulates cell proliferation,and induces differentiation to small post-mitotic pre-B cells that further undergo the rearrangement of the IgL chain genes.Recent advances in elucidating the key roles of pre-BCR in B cell development have provided a better understanding of normal B lymphopoiesis and its dysregulated state leading to B cell neoplasia.Cellular & Molecular Immunology.2004;1(2):89-94.
基金supported by the National Natural Science Foundation of China(Nos.31770441,31971415).
文摘Decabrominated diphenyl ether(BDE-209)is generally utilized in multiple polymer materials as common brominated flame retardant.BDE-209 has been listed as persistent organic pollutants(POPs),which was considered to be reproductive toxin in the environment.But it still remains unclear about the effects of BDE-209 on DNA methylation and the inducedmale reproductive toxicity.Due to the extensive epigenetic regulation in germ line development,we hypothesize that BDE-209 exposure impacts the statue of DNA methylation in spermatocytes in vitro.Therefore,the mouse GC-2spd(GC-2)cells were used for the genome wide DNA methylation analysis after treated with 32μg/mL BDE-209 for 24 hr.The results showed that BDE-209 caused genomic methylation changes with 32,083 differentially methylated CpGs in GC-2 cells,including 16,164(50.38%)hypermethylated and 15,919(49.62%)hypomethylated sites.With integrated analysis ofDNAmethylation data and functional enrichment,we found that BDE-209 might affect the functional transcription in cell growth and sperm development by differential gene methylation.qRT-PCR validation demonstrated the involvement of p53-dependent DNA damage response in the GC-2 cells after BDE-209 exposure.In general,our findings indicated that BDE-209-induced genome wide methylation changes could be interrelated with reproductive dysfunction.This study might provide new insights into the mechanisms of male reproductive toxicity under the environmental exposure to BDE-209.
文摘Methylation of adenosine base on the nitrogen-6 position （N6-methyladenosine, m^6A） is the most common and abundant modification on mRNA transcripts. This post-transcriptional modification was first described in the 1970s in hepatoma cells （Desrosiers et al., 1974）.
文摘The RNA editing enzyme ADAR1 has been shown to be an essential molecule for hematopoietic cell differentiation,embryonic development,and regulation of immune responses.Here,we present evidence in a T-cell-specific gene knockout mouse model that ADAR1 is required for early T cell development.Loss of ADAR1 led to cell death of the progenitors at the double negative stage and prevented T cell maturation in the thymus.Furthermore,ADAR1 deletion in pre-T cells preferentially affected TCRb-expressing cells causing TCRb positive cell depletion.Interruption of IFN signaling occurred in the premature T cells,indicating a role of IFN signaling in the survival of TCRb-expressing cells regulated by ADAR1.This study demonstrated an essential role for the RNA editing enzyme ADAR1 as a potential regulator for T-cell fate determination during clonal selection,which,in turn,contributes to immunologic homeostasis.
文摘Laboratory mice have widely been used as tools for basic biological research and models for studying human diseases.With the advances of genetic engineering and conditional knockout(CKO)mice,we now understand hematopoiesis is a dynamic stepwise process starting from hematopoietic stem cells(HSCs)which are responsible for replenishing all blood cells.Transcriptional factors play important role in hematopoiesis.In this review we compile several studies on using genetic modified mice and humanized mice to study function of transcriptional factors in lymphopoiesis,including T lymphocyte and Natural killer(NK)cell development.Finally,we focused on the key transcriptional factor Bcl11b and its function in regulating T cell specification and commitment.
文摘This study was designed to explore the possibility of using ascitic mouse sarcoma cell line (S180) to validate the mouse tumor cell attachment assay for developmental toxicants, and to test the inhibitory effects of various developmental toxicants. The results showed that 2 of 3 developmental toxicants under consideration, sodium pentobarbital and ethanol, significantly inhibited S180cells attachment to Concanavalin A-coaed surfaces. Inhibition was dependent on concentration, and the IC50 (the concentration tha reduced attachment by 50% ), of these 2 chemicals was 1.2×10-3mol/L and 1 .0 mol/L, respectively. Anoher developmental toxiant, hydmiortisone, did not show inhibitory activity. Two non-developmental toxicants, sodium chloride and glycine were also tested and these did not decrease attachment rates. The main results reported here were generally sindlar to those obtained with ascitic mouse ovdrian tumor cells as a model. Therefore, this study added further evidence to the conclusion that cell specificity does not lindt attachment inhibition to Con A-coated surfaces, so S180 cell may serve as an altemative cell model, especially when other cell lines are unavailable. Furthermore, after optimal validation, it can be suggested that an S180 cell attachment assay may be a candidate for a series of assays to detect developmental toxicants.
基金supported by grants from the National Natural Science Foundation of China(Grant Nos.81602599,31400752,81771781,and U1804281)the National Key Research and Development Program of China(Grant No.2016YFC1303501)。
文摘Objective:Esophageal squamous cell carcinoma(ESCC)has high morbidity and mortality rates worldwide.Cancer stem cells(CSCs)may cause tumor initiation,metastasis,and recurrence and are also responsible for chemotherapy and radiotherapy failures.Myeloid-derived suppressor cells(MDSCs),in contrast,are known to be involved in mediating immunosuppression.Here,we aimed to investigate the mechanisms of interaction of CSCs and MDSCs in the tumor microenvironment.Methods:ESCC tissues and cell lines were evaluated.Neural precursor cell expressed,developmentally downregulated 9(NEDD9)was knocked down and overexpressed by lentiviral transfection.Quantitative PCR,Western blot,immunohistochemistry,cell invasion,flow cytometry,cell sorting,multiplex chemokine profiling,and tumor growth analyses were performed.Results:Microarray analysis revealed 10 upregulated genes in esophageal CSCs.Only NEDD9 was upregulated in CSCs using the sphere-forming method.NEDD9 expression was correlated with tumor invasion(P=0.0218),differentiation(P=0.0153),and poor prognosis(P=0.0373).Additionally,NEDD9 was required to maintain the stem-like phenotype.Screening of chemokine expression in ESCC cells with NEDD9 overexpression and knockdown showed that NEDD9 regulated C-X-C motif chemokine ligand 8(CXCL8)expression via the ERK pathway.CXCL8 mediated the recruitment of MDSCs induced by NEDD9 in vitro and in vivo.MDSCs promoted the stemness of ESCC cells through NEDD9 via the Notch pathway.Conclusions:As a marker of ESCC,NEDD9 maintained the stemness of ESCC cells and regulated CXCL8 through the ERK pathway to recruit MDSCs into the tumor,suggesting NEDD9 as a therapeutic target and novel prognostic marker for ESCC.
基金Supported by the National Natural Science Foundation of China,No.81670951
文摘Stem cells(SCs)with their self-renewal and pluripotent differentiation potential,show great promise for therapeutic applications to some refractory diseases such as stroke,Parkinsonism,myocardial infarction,and diabetes.Furthermore,as seed cells in tissue engineering,SCs have been applied widely to tissue and organ regeneration.However,previous studies have shown that SCs are heterogeneous and consist of many cell subpopulations.Owing to this heterogeneity of cell states,gene expression is highly diverse between cells even within a single tissue,making precise identification and analysis of biological properties difficult,which hinders their further research and applications.Therefore,a defined understanding of the heterogeneity is a key to research of SCs.Traditional ensemble-based sequencing approaches,such as microarrays,reflect an average of expression levels across a large population,which overlook unique biological behaviors of individual cells,conceal cell-to-cell variations,and cannot understand the heterogeneity of SCs radically.The development of high throughput single cell RNA sequencing(scRNA-seq)has provided a new research tool in biology,ranging from identification of novel cell types and exploration of cell markers to the analysis of gene expression and predicating developmental trajectories.scRNA-seq has profoundly changed our understanding of a series of biological phenomena.Currently,it has been used in research of SCs in many fields,particularly for the research of heterogeneity and cell subpopulations in early embryonic development.In this review,we focus on the scRNA-seq technique and its applications to research of SCs.
基金Supported by A RCUK fellowship,EP/E500145/1,to Hay DCA grant from the Edinburgh Bioquarter,to Medine CNChina Scholarship Council,No.2010658022,to Zhou WL
文摘Human stem cells are scalable cell populations capable of cellular differentiation.This makes them a very attractive in vitro cellular resource and in theory provides unlimited amounts of primary cells.Such an approach has the potential to improve our understanding of human biology and treating disease.In the future it may be possible to deploy novel stem cell-based approaches to treat human liver diseases.In recent years,eff icient hepatic differentiation from human stem cells has been achieved by several research groups including our own.In this review we provide an overview of the f ield and discuss the future potential and limitations of stem cell technology.
基金the Coordination for the Improvement of Higher Education Personnel(CAPES),No.88882.366181/2019-01the Carlos Chagas Filho Foundation for Research Support of the State of Rio de Janeiro(FAPERJ),No.E-26/202.682/2018National Council for Scientific and Technological Development(CNPq),No.467513/2014-7
文摘Scaffold-free techniques in the developmental tissue engineering area are designed to mimic in vivo embryonic processes with the aim of biofabricating,in vitro,tissues with more authentic properties.Cell clusters called spheroids are the basis for scaffold-free tissue engineering.In this review,we explore the use of spheroids from adult mesenchymal stem/stromal cells as a model in the developmental engineering area in order to mimic the developmental stages of cartilage and bone tissues.Spheroids from adult mesenchymal stromal/stem cells lineages recapitulate crucial events in bone and cartilage formation during embryogenesis,and are capable of spontaneously fusing to other spheroids,making them ideal building blocks for bone and cartilage tissue engineering.Here,we discuss data from ours and other labs on the use of adipose stromal/stem cell spheroids in chondrogenesis and osteogenesis in vitro.Overall,recent studies support the notion that spheroids are ideal"building blocks"for tissue engineering by“bottom-up”approaches,which are based on tissue assembly by advanced techniques such as three-dimensional bioprinting.Further studies on the cellular and molecular mechanisms that orchestrate spheroid fusion are now crucial to support continued development of bottom-up tissue engineering approaches such as three-dimensional bioprinting.
文摘Smoking during pregnancy is a major source of fetal exposure to numerous harmful agents present in tobacco smoke. Lung development involves complex biochemical processes resulting in dramatic changes which continue even after birth. In addition to type I cells which form the blood-air barrier, type II alveolar epithelial (AE) cells have important and diverse functions related to immunological protection and stabilization of the alveolus through synthesis and secretion of the pulmonary surfactant. Apoptosis or programmed cells death is an important physiological process during lung embryogenesis and for the proper maintenance of homeostasis. Caspases are proteases that play important roles in regulating apoptosis. Caspase-3 is the key executioner caspase in the cascade of events leading to cell death by apoptosis. We explored the hypothesis that cigarette smoke extract (CSE) induces apoptosis in fetal rat lung type II AE cells by activation of caspase-3. To analyze these factors, isolated fetal rat lung type II AE cells were used. The cells were exposed to different concentrations of CSE (5%, 10% or 15%) (v/v) for 60 min. The results of the present study showed that CSE induced apoptosis in fetal rat lung type II AE cells with a significant increase (p 0.05) in caspase-3 activity and decrease in cell proliferation at CSE concentrations of 10% and 15% (v/v). These observations indicate that cigarette smoke extract induces apoptosis by activation of caspase-3 in fetal rat lung type II AE cells in a dose-dependent manner and may potentially alter the regulated development of the lung and the appearance of the surfactant-producing type II alveolar cells which are critical for the establishment of adequate gas exchange at birth.
