为了探讨小鼠胚胎主动脉-性腺-中肾(aorta-gonad-mesonephros,AGM)区基质微环境对胚胎造血的作用,分离鉴定小鼠背主动脉(dorsalaorta,DA)来源间充质干细胞样基质细胞(mesenchymal stem cell like stromal cells,MSC like stromal cells...为了探讨小鼠胚胎主动脉-性腺-中肾(aorta-gonad-mesonephros,AGM)区基质微环境对胚胎造血的作用,分离鉴定小鼠背主动脉(dorsalaorta,DA)来源间充质干细胞样基质细胞(mesenchymal stem cell like stromal cells,MSC like stromal cells)并研究其生长特性、表面标志和间质分化能力。取E11.5小鼠胚胎,分离获得DA区细胞,转染质粒pSV3neo-SV40,筛选具有G418抗性的阳性细胞,挑取成纤维样细胞,传代培养并检测其增殖能力,应用流式细胞术检测相关表面标志,诱导其向脂肪、成骨和成软骨细胞分化。结果表明:筛选获得的20个细胞克隆多为成纤维样细胞。mDAF3和mDAF18可在体外传代50代以上,稳定表达G418抗性,细胞倍增时间约为24小时,具有向成骨细胞、脂肪细胞和成软骨细胞分化的能力,流式细胞术检测结果显示其表达CD29、CD44、CD105、Sca-1,弱表达CD34,CD45和CD31。结论:永生化的mDAF3和mDAF18具有MSC的表型特征和分化功能,提示小鼠胚胎DA区可能存在MSC,小鼠胚胎DA区MSC样基质细胞可为研究基质微环境对胚胎造血发育的调控作用提供支持细胞。展开更多
This study was designed to investigate the expression of aminopeptidase N (APN)/CD13 on intraembryonic AGM stromal cells, and the change of its enzymatic activity after irradiation injury. The expression of APN/CD13...This study was designed to investigate the expression of aminopeptidase N (APN)/CD13 on intraembryonic AGM stromal cells, and the change of its enzymatic activity after irradiation injury. The expression of APN/CD13 on AGM stromal cells was assayed by RT-PCR and immunihistochemistry. After the stromal cells in AGM region were irradiated with 8.0 Gy of ^60Co T-rays, APN/CD13 enzymatic activity was measured by spectrophotometer at different time points. The result showed that AGM stromal cells strongly expressed APN/CD13. The enzymatic activity of APN/CD13 decreased temporarily after irradiation injury, then increased to higher level 4 h after irradiation, and it returned to the pre-irradiation level 24 to 48 h after the irradiation. The enzymatic activity of APN/CD13 was temporarily enhanced after irradiation injury, which might be one of the compensatory mechanisms that promote the hematopoietic recovery after irradiation.展开更多
The functional heterogeneity of hematopoietic stem cells(HSCs) has been comprehensively investigated by single-cell transplantation assay.However,the heterogeneity regarding their physiological contribution remains an...The functional heterogeneity of hematopoietic stem cells(HSCs) has been comprehensively investigated by single-cell transplantation assay.However,the heterogeneity regarding their physiological contribution remains an open question,especially for those with life-long hematopoietic fate of rigorous selfrenewing and balanced differentiation capacities.In this study,we revealed that Procr expression was detected principally in phenotypical vascular endothelium co-expressing DII4 and CD44 in the midgestation mouse embryos,and could enrich all the HSCs of the embryonic day 11.5(E11.5) aortagonad-mesonephros(AGM) region.We then used a temporally restricted genetic tracing strategy to irreversibly label the Procr-exp res sing cells at E9.5.Interestingly,most labeled mature HSCs in multiple sites(such as AGM) around E11.5 were functionally categorized as lymphomyeloid-balanced HSCs assessed by direct transplantation.Furthermore,the labeled cells contributed to an average of 7.8% of immunophenotypically defined HSCs in E14.5 fetal liver(FL) and 6.9% of leukocytes in peripheral blood(PB) during one-year follow-up.Surprisingly,in aged mice of 24 months,the embryonically tagged cells displayed constant contribution to leukocytes with no bias to myeloid or lymphoid lineages.Altogether,we demonstrated,for the first time,the existence of a subtype of physiologically long-lived balanced HSCs as hypothesized,whose precise embryonic origin and molecular identity await further characterization.展开更多
文摘为了探讨小鼠胚胎主动脉-性腺-中肾(aorta-gonad-mesonephros,AGM)区基质微环境对胚胎造血的作用,分离鉴定小鼠背主动脉(dorsalaorta,DA)来源间充质干细胞样基质细胞(mesenchymal stem cell like stromal cells,MSC like stromal cells)并研究其生长特性、表面标志和间质分化能力。取E11.5小鼠胚胎,分离获得DA区细胞,转染质粒pSV3neo-SV40,筛选具有G418抗性的阳性细胞,挑取成纤维样细胞,传代培养并检测其增殖能力,应用流式细胞术检测相关表面标志,诱导其向脂肪、成骨和成软骨细胞分化。结果表明:筛选获得的20个细胞克隆多为成纤维样细胞。mDAF3和mDAF18可在体外传代50代以上,稳定表达G418抗性,细胞倍增时间约为24小时,具有向成骨细胞、脂肪细胞和成软骨细胞分化的能力,流式细胞术检测结果显示其表达CD29、CD44、CD105、Sca-1,弱表达CD34,CD45和CD31。结论:永生化的mDAF3和mDAF18具有MSC的表型特征和分化功能,提示小鼠胚胎DA区可能存在MSC,小鼠胚胎DA区MSC样基质细胞可为研究基质微环境对胚胎造血发育的调控作用提供支持细胞。
基金This project was supported by a grant from the National Natural Sciences Foundation of China (No. 30570773 )
文摘This study was designed to investigate the expression of aminopeptidase N (APN)/CD13 on intraembryonic AGM stromal cells, and the change of its enzymatic activity after irradiation injury. The expression of APN/CD13 on AGM stromal cells was assayed by RT-PCR and immunihistochemistry. After the stromal cells in AGM region were irradiated with 8.0 Gy of ^60Co T-rays, APN/CD13 enzymatic activity was measured by spectrophotometer at different time points. The result showed that AGM stromal cells strongly expressed APN/CD13. The enzymatic activity of APN/CD13 decreased temporarily after irradiation injury, then increased to higher level 4 h after irradiation, and it returned to the pre-irradiation level 24 to 48 h after the irradiation. The enzymatic activity of APN/CD13 was temporarily enhanced after irradiation injury, which might be one of the compensatory mechanisms that promote the hematopoietic recovery after irradiation.
基金supported by grants from the National Key R&D Program of China (2017YFA0103401 and 2016YFA0100601)the National Natural Science Foundation of China(31425012,31930054,31871173 and 81890991)the Program for Guangdong Introducing Innovative and Entrepreneurial Teams (2017ZT07S347)
文摘The functional heterogeneity of hematopoietic stem cells(HSCs) has been comprehensively investigated by single-cell transplantation assay.However,the heterogeneity regarding their physiological contribution remains an open question,especially for those with life-long hematopoietic fate of rigorous selfrenewing and balanced differentiation capacities.In this study,we revealed that Procr expression was detected principally in phenotypical vascular endothelium co-expressing DII4 and CD44 in the midgestation mouse embryos,and could enrich all the HSCs of the embryonic day 11.5(E11.5) aortagonad-mesonephros(AGM) region.We then used a temporally restricted genetic tracing strategy to irreversibly label the Procr-exp res sing cells at E9.5.Interestingly,most labeled mature HSCs in multiple sites(such as AGM) around E11.5 were functionally categorized as lymphomyeloid-balanced HSCs assessed by direct transplantation.Furthermore,the labeled cells contributed to an average of 7.8% of immunophenotypically defined HSCs in E14.5 fetal liver(FL) and 6.9% of leukocytes in peripheral blood(PB) during one-year follow-up.Surprisingly,in aged mice of 24 months,the embryonically tagged cells displayed constant contribution to leukocytes with no bias to myeloid or lymphoid lineages.Altogether,we demonstrated,for the first time,the existence of a subtype of physiologically long-lived balanced HSCs as hypothesized,whose precise embryonic origin and molecular identity await further characterization.