GM2 gangliosidoses are a group of autosomal-recessive lysosomal storage disorde rs.These diseases result from a deficiency of lysosomal enzymeβ-hexosaminidase A(HexA),which is responsible for GM2 ganglioside degradat...GM2 gangliosidoses are a group of autosomal-recessive lysosomal storage disorde rs.These diseases result from a deficiency of lysosomal enzymeβ-hexosaminidase A(HexA),which is responsible for GM2 ganglioside degradation.HexA deficiency causes the accumulation of GM2-gangliosides mainly in the nervous system cells,leading to severe progressive neurodegeneration and neuroinflammation.To date,there is no treatment for these diseases.Cell-mediated gene therapy is considered a promising treatment for GM2 gangliosidoses.This study aimed to evaluate the ability of genetically modified mesenchymal stem cells(MSCs-HEXA-HEXB)to restore HexA deficiency in Tay-Sachs disease patient cells,as well as to analyze the functionality and biodistribution of MSCs in vivo.The effectiveness of HexA deficiency cross-correction was shown in mutant MSCs upon intera ction with MSCs-HEXA-HEXB.The results also showed that the MSCs-HEXA-HEXB express the functionally active HexA enzyme,detectable in vivo,and intravenous injection of the cells does not cause an immune response in animals.These data suggest that genetically modified mesenchymal stem cells have the potentials to treat GM2 gangliosidoses.展开更多
Tay-Sachs disease and Sandhoff disease are severe hereditary neurodegenerative disorders caused by a deficiency ofβ-hexosaminidase A(HexA)enzyme,which results in the accumulation of GM2 gangliosides in the nervous sy...Tay-Sachs disease and Sandhoff disease are severe hereditary neurodegenerative disorders caused by a deficiency ofβ-hexosaminidase A(HexA)enzyme,which results in the accumulation of GM2 gangliosides in the nervous system cells.In this work,we analyzed the efficacy and safety of cell-mediated gene therapy for Sandhoff disease and Sandhoff disease using a bicistronic lentiviral vector encoding cDNA of HexAα-andβ-subunit genes separated by the nucleotide sequence of a P2A peptide(HEXA-HEXB).The functionality of the bicistronic construct containing the HEXA-HEXB genetic cassette was analyzed in a culture of HEK293T cells and human umbilical cord blood mononuclear cells(hUCBMCs).Our results showed that the enzymatic activity of HexA in the conditioned medium harvested from genetically modified HEK293T-HEXA-HEXB and hUCBMCs-HEXA-HEXB was increased by 23 and 8 times,respectively,compared with the conditioned medium of native cells.Western blot analysis showed that hUCBMCs-HEXA-HEXB secreted both completely separated HEXA and HEXB proteins,and an uncleaved protein containing HEXA+HEXB linked by the P2A peptide.Intravenous injection of genetically modified hUCBMCs-HEXA-HEXB to laboratory Wistar rats was carried out,and the HexA enzymatic activity in the blood plasma of experimental animals,as well as the number of live cells of immune system organs(spleen,thymus,bone marrow,lymph nodes)were determined.A significant increase in the enzymatic activity of HexA in the blood plasma of laboratory rats on days 6 and 9(by 2.5 and 3 times,respectively)after the administration of hUCBMCsHEXA-HEXB was shown.At the same time,the number of live cells in the studied organs remained unchanged.Thus,the functionality of the bicistronic genetic construct encoding cDNA of the HEXA and HEXB genes separated by the nucleotide sequence of the P2A peptide was shown in vitro and in vivo.We hypothesize that due to the natural ability of hUCBMCs to overcome biological barriers,such a strategy can restore the activity of the missing enzyme in the展开更多
目的研究资木瓜总苷对小鼠骨髓来源的肥大细胞(BMMC)脱颗粒影响。方法从C57BL/6小鼠股骨获得骨髓细胞,用含100 m L/L胎牛血清、20 ng/m L IL-3和40 ng/m L干细胞因子(SCF)的RPMI1640培养基,培养4周;流式细胞术检测CD117、FcεRIα双阳...目的研究资木瓜总苷对小鼠骨髓来源的肥大细胞(BMMC)脱颗粒影响。方法从C57BL/6小鼠股骨获得骨髓细胞,用含100 m L/L胎牛血清、20 ng/m L IL-3和40 ng/m L干细胞因子(SCF)的RPMI1640培养基,培养4周;流式细胞术检测CD117、FcεRIα双阳性细胞的比例,甲苯胺蓝染色法观察细胞的成熟度。资木瓜总苷与诱导成功的BMMC共培养,CCK-8法检测资木瓜总苷对BMMC的毒性作用,荧光分光光度法定量检测β-己糖胺酶释放量,并计算其释放率,ELISA检测类胰蛋白酶释放量。结果原代培养诱导4周后,CD117和FcεRIα双阳性细胞比例大于95%,且核被染蓝色,胞质为紫红色,呈现肥大细胞特性。(0.01、0.03、0.10)mg/m L的资木瓜总苷作用12 h,对BMMC无毒性作用。与空白对照组相比,资木瓜总苷与交联牛血清白蛋白的二硝基苯半抗原(DNP-BSA)、A23187刺激的BMMC作用后,细胞的β-己糖胺酶释放率和类胰蛋白酶的释放量均显著降低。结论资木瓜总苷对不同抗原刺激原代培养的小鼠BMMC脱颗粒具有显著抑制作用,且存在量效关系。展开更多
Aims: To study RBL-2H3 cell degranulation phenomena induced by some TCMIs through cell morphological and ultra-structural observation, released enzyme activity and establish RBL-2H3 cell degranulation test indicated ...Aims: To study RBL-2H3 cell degranulation phenomena induced by some TCMIs through cell morphological and ultra-structural observation, released enzyme activity and establish RBL-2H3 cell degranulation test indicated by β- hexosaminidase activity as a method to evaluate TCMIs at nonclinical stage. Methods: RBL-2H3 cells were used to study the degranulation by co-culture with positive control C48/80 and some TCMIs through morphological and ultra-structure observation, β-hexosaminidase activity detection. RBL-2H3 cell degranulation test was established to detect β-hexosaminidase activity caused by 17 kinds of TCMIs and their ingredients. The cytotoxicity effect of some TCMIs on both RBL 2H3 and BRL cells was measured by CCK-8 assay. Results: Toluidine blue staining and ultra-structure of electronic microscope observation of treated RBL-2H3 cells showed degranulation morphologically. Detection of β-hexosaminidase activity in the supernatant of treated cells showed some TCMIs had elevated enzyme release rates. Further analysis of the ingredients and compound in Tanreqing Injection and Shengmai Injection showed Scutellaria baicalensis Georgi in Tanreqing Injection, Red ginseng and Fructus Schisandrae Chinensis in Shengmai Injection were responsible to the degranulation of RBL-2H3 cells. Osmotic pressures and pH influenced RBL-2H3 degranulation. High Osmotic pressure of Tanreqing Injection and low pH of chlorogenic acid at 2.5 and 5.0 mmol/L congcentration might be responsible to high β-hexosaminidase activity. Most of the TCMIs inducing degranulation had cytotoxicity effect for both RBL-2H3 and BRL cells, but some TCMIs inducing degranulation had no cytotoxicity effect. Conclusion: Some TCMIs can induce degranulation of RBL-2H3 cells;RBL-2H3 cell degranulation test can be used in non-clinical stage to detect the risk causing anaphylactoid reactions. Osmotic pressures and pH influenced RBL-2H3 degranulation, and they should be measured before testing. The mechanism of degranulation caused by some TCMIs is cytotoxic展开更多
基金supported by the subsidy allocated to Kazan Federal University for the state assignment#0671-2020-0058 in the sphere of scientific activities(to AAR)the Kazan Federal University Strategic Academic Leadership Program(PRIORITY-2030)。
文摘GM2 gangliosidoses are a group of autosomal-recessive lysosomal storage disorde rs.These diseases result from a deficiency of lysosomal enzymeβ-hexosaminidase A(HexA),which is responsible for GM2 ganglioside degradation.HexA deficiency causes the accumulation of GM2-gangliosides mainly in the nervous system cells,leading to severe progressive neurodegeneration and neuroinflammation.To date,there is no treatment for these diseases.Cell-mediated gene therapy is considered a promising treatment for GM2 gangliosidoses.This study aimed to evaluate the ability of genetically modified mesenchymal stem cells(MSCs-HEXA-HEXB)to restore HexA deficiency in Tay-Sachs disease patient cells,as well as to analyze the functionality and biodistribution of MSCs in vivo.The effectiveness of HexA deficiency cross-correction was shown in mutant MSCs upon intera ction with MSCs-HEXA-HEXB.The results also showed that the MSCs-HEXA-HEXB express the functionally active HexA enzyme,detectable in vivo,and intravenous injection of the cells does not cause an immune response in animals.These data suggest that genetically modified mesenchymal stem cells have the potentials to treat GM2 gangliosidoses.
基金funded by the subsidy allocated to Kazan Federal University for the state assignment#0671-2020-0058 in the sphere of scientific activities。
文摘Tay-Sachs disease and Sandhoff disease are severe hereditary neurodegenerative disorders caused by a deficiency ofβ-hexosaminidase A(HexA)enzyme,which results in the accumulation of GM2 gangliosides in the nervous system cells.In this work,we analyzed the efficacy and safety of cell-mediated gene therapy for Sandhoff disease and Sandhoff disease using a bicistronic lentiviral vector encoding cDNA of HexAα-andβ-subunit genes separated by the nucleotide sequence of a P2A peptide(HEXA-HEXB).The functionality of the bicistronic construct containing the HEXA-HEXB genetic cassette was analyzed in a culture of HEK293T cells and human umbilical cord blood mononuclear cells(hUCBMCs).Our results showed that the enzymatic activity of HexA in the conditioned medium harvested from genetically modified HEK293T-HEXA-HEXB and hUCBMCs-HEXA-HEXB was increased by 23 and 8 times,respectively,compared with the conditioned medium of native cells.Western blot analysis showed that hUCBMCs-HEXA-HEXB secreted both completely separated HEXA and HEXB proteins,and an uncleaved protein containing HEXA+HEXB linked by the P2A peptide.Intravenous injection of genetically modified hUCBMCs-HEXA-HEXB to laboratory Wistar rats was carried out,and the HexA enzymatic activity in the blood plasma of experimental animals,as well as the number of live cells of immune system organs(spleen,thymus,bone marrow,lymph nodes)were determined.A significant increase in the enzymatic activity of HexA in the blood plasma of laboratory rats on days 6 and 9(by 2.5 and 3 times,respectively)after the administration of hUCBMCsHEXA-HEXB was shown.At the same time,the number of live cells in the studied organs remained unchanged.Thus,the functionality of the bicistronic genetic construct encoding cDNA of the HEXA and HEXB genes separated by the nucleotide sequence of the P2A peptide was shown in vitro and in vivo.We hypothesize that due to the natural ability of hUCBMCs to overcome biological barriers,such a strategy can restore the activity of the missing enzyme in the
文摘目的研究资木瓜总苷对小鼠骨髓来源的肥大细胞(BMMC)脱颗粒影响。方法从C57BL/6小鼠股骨获得骨髓细胞,用含100 m L/L胎牛血清、20 ng/m L IL-3和40 ng/m L干细胞因子(SCF)的RPMI1640培养基,培养4周;流式细胞术检测CD117、FcεRIα双阳性细胞的比例,甲苯胺蓝染色法观察细胞的成熟度。资木瓜总苷与诱导成功的BMMC共培养,CCK-8法检测资木瓜总苷对BMMC的毒性作用,荧光分光光度法定量检测β-己糖胺酶释放量,并计算其释放率,ELISA检测类胰蛋白酶释放量。结果原代培养诱导4周后,CD117和FcεRIα双阳性细胞比例大于95%,且核被染蓝色,胞质为紫红色,呈现肥大细胞特性。(0.01、0.03、0.10)mg/m L的资木瓜总苷作用12 h,对BMMC无毒性作用。与空白对照组相比,资木瓜总苷与交联牛血清白蛋白的二硝基苯半抗原(DNP-BSA)、A23187刺激的BMMC作用后,细胞的β-己糖胺酶释放率和类胰蛋白酶的释放量均显著降低。结论资木瓜总苷对不同抗原刺激原代培养的小鼠BMMC脱颗粒具有显著抑制作用,且存在量效关系。
文摘Aims: To study RBL-2H3 cell degranulation phenomena induced by some TCMIs through cell morphological and ultra-structural observation, released enzyme activity and establish RBL-2H3 cell degranulation test indicated by β- hexosaminidase activity as a method to evaluate TCMIs at nonclinical stage. Methods: RBL-2H3 cells were used to study the degranulation by co-culture with positive control C48/80 and some TCMIs through morphological and ultra-structure observation, β-hexosaminidase activity detection. RBL-2H3 cell degranulation test was established to detect β-hexosaminidase activity caused by 17 kinds of TCMIs and their ingredients. The cytotoxicity effect of some TCMIs on both RBL 2H3 and BRL cells was measured by CCK-8 assay. Results: Toluidine blue staining and ultra-structure of electronic microscope observation of treated RBL-2H3 cells showed degranulation morphologically. Detection of β-hexosaminidase activity in the supernatant of treated cells showed some TCMIs had elevated enzyme release rates. Further analysis of the ingredients and compound in Tanreqing Injection and Shengmai Injection showed Scutellaria baicalensis Georgi in Tanreqing Injection, Red ginseng and Fructus Schisandrae Chinensis in Shengmai Injection were responsible to the degranulation of RBL-2H3 cells. Osmotic pressures and pH influenced RBL-2H3 degranulation. High Osmotic pressure of Tanreqing Injection and low pH of chlorogenic acid at 2.5 and 5.0 mmol/L congcentration might be responsible to high β-hexosaminidase activity. Most of the TCMIs inducing degranulation had cytotoxicity effect for both RBL-2H3 and BRL cells, but some TCMIs inducing degranulation had no cytotoxicity effect. Conclusion: Some TCMIs can induce degranulation of RBL-2H3 cells;RBL-2H3 cell degranulation test can be used in non-clinical stage to detect the risk causing anaphylactoid reactions. Osmotic pressures and pH influenced RBL-2H3 degranulation, and they should be measured before testing. The mechanism of degranulation caused by some TCMIs is cytotoxic
文摘目的筛选针对Orai1分子第1膜外区蛋白的核酸适配体,探讨适配体通过拮抗钙离子释放激活通道(Ca2+release activation channel,CRAC)抑制肥大细胞活化的效应。方法构建随机单链DNA文库,利用不对称PCR对单链DNA文库进行扩增。采用聚苯乙烯酶联板为介质的指数富集配体系统进化(systematic evolution of ligand by exponential enrichment,SELEX)技术筛选核酸适配体。利用酶联免疫吸附实验检测各轮筛选序列与靶蛋白的亲和力,验证适配体与靶蛋白的特异性结合;激光共聚焦显微镜观察适配体对细胞内钙离子浓度变化的影响;利用IgE介导的肥大细胞脱颗粒模型,观察适配体对β-氨基己糖苷酶释放的抑制效应。结果经过12轮SELEX筛选,获得了7条核酸适配体,其中AptamerY1解离常数(Kd值)为1.72×10-8mol/L。以终浓度2μg/mL的AptamerY1可抑制由IgE介导的人肥大细胞系LAD2钙离子内流,并对LAD2细胞的β-氨基己糖苷酶释放抑制率达95%。结论通过SELEX筛选,获得了7条针对Orai1分子第1膜外区的核酸适配体,所获得适配体可对肥大细胞LAD2钙内流有效抑制,进而抑制肥大细胞活化和β-氨基己糖苷酶的释放。
