Hemophilia B is a hemorrhagic disease caused by the deficiency of clotting factor IX （FIX）. Gene therapy might be the ultimate strategy for the disease. However, two main problems that should be solved in gene thera...Hemophilia B is a hemorrhagic disease caused by the deficiency of clotting factor IX （FIX）. Gene therapy might be the ultimate strategy for the disease. However, two main problems that should be solved in gene therapy for hemophilia B are immunity and safety. Self-complementary adeno-assoeiated virus serotype 8 （scAAV8）, a non-human primate AAV featuring low immunogenicity and high transfection efficiency in liver cells, might be a potential vector for hemophilia B gene therapy. A strong fiver-specific promoter-1 （LP1） was inserted and mutant human FIX Arg338Ala was introduced into plasmid scAAV8-LP1 to develop an optimized AAV8 vector that expresses human clotting factor FIX （hFIX）. The efficiency of scAAV8-LPI-hFIX administered through normal systemic injection or hydrodynamic injection was compared. A high expression was achieved using hydrodynamic injection, and the peak hFIX expression levels in the 5 × 10^11 and 1 × 10^11 virus genome （vg） cohorts were 31.94% and 25.02% of normal level, respectively, at 60 days post-injection. From the perspective of long-term （200 days） expression, both injection methods presented promising results with the concentration value maintained above 4% of normal plasma. The results were further verified by enzyme-linked immunosorbent assay and activated partial thromboplastin time. Our study provides a potential gene therapy method for hemophilia B.展开更多
Precise targeting of specific regions within the central nervous system(CNS)is crucial for both scientific research and gene therapy in the context of brain diseases.Adeno-associated virus 13(AAV13)is known for its re...Precise targeting of specific regions within the central nervous system(CNS)is crucial for both scientific research and gene therapy in the context of brain diseases.Adeno-associated virus 13(AAV13)is known for its restricted diffusion range within the CNS,making it an ideal choice for precise labeling and administration within small brain regions.However,AAV13 mediates relatively low expression of target genes.Here,we introduced specifically engineered modifications to the AAV13 capsid protein to enhance its transduction efficiency.We first constructed AAV13-YF by mutating tyrosine to phenylalanine on the surface of the AAV13 capsid.We then inserted the 7m8 peptide,known to enhance cell transduction,into positions 587/588 and 585/586 of the AAV13 capsid,resulting in two distinct variants named AAV13-587-7m8 and AAV13-585-7m8,respectively.We found that AAV13-YF exhibited superior in vitro infectivity in HEK293T cells compared to AAV13,while AAV13-587-7m8 and AAV13-585-7m8 showed enhanced CNS infection capabilities in C57BL/6 mice,with AAV13-587-7m8 infection retaining a limited spread range.These modified AAV13 variants hold promising potential for applications in gene therapy and neuroscience research.展开更多
AIM To stably correct tyrosinaemia in proliferating livers of fumarylacetoacetate-hydrolase knockout(Fah-/-) mice by homologous-recombination-mediated targeted addition of the Fah gene.METHODS C57 BL/6 Fah?exon5 mice ...AIM To stably correct tyrosinaemia in proliferating livers of fumarylacetoacetate-hydrolase knockout(Fah-/-) mice by homologous-recombination-mediated targeted addition of the Fah gene.METHODS C57 BL/6 Fah?exon5 mice served as an animal model for human tyrosinaemia type 1 in our study. The vector was created by amplifying human Fah c DNA including the TTR promoter from a lentivirus plasmid as described. The Fah expression cassette was flanked by homologous arms(620 bp and 749 bp long) of the Rosa26 gene locus. Mice were injected with 2.1 × 108 VP of this vector(r AAV8-ROSA26.HAL-TTR.FahROSA26.HAR) via the tail vein. Mice in the control group were injected with 2.1 × 108 VP of a similar vector but missing the homologous arms(r AAV8-TTR.Fah). Primary hepatocytes from Fah-/-recipient mice, treated with our vectors, were isolated and 1 × 106 hepatocytes were transplanted into secondary Fah-/-recipient mice by injection into the spleen. Upon either vector application or hepatocyte transplantation NTBC treatment was stopped in recipient mice. RESULTS Here, we report successful HR-mediated genome editing by integration of a Fah gene expression cassette into the "safe harbour locus" Rosa26 by recombinant AAV8. Both groups of mice showed long-term survival, weight gain and FAH positive clusters as determined by immunohistochemistry analysis of liver sections in the absence of NTBC treatment. In the group of C57 BL/6 Fah?exon5 mice, which have been transplanted with hepatocytes from a mouse injected with r AAV8-ROSA26.HAL-TTR.Fah-ROSA26.HAR 156 d before, 6 out of 6 mice showed long-term survival, weight gain and FAH positive clusters without need for NTBC treatment. In contrast only 1 out 5 mice, who received hepatocytes from r AAV8-TTR.Fah treated mice, survived and showed few and smaller FAH positive clusters. These results demonstrate that homologous recombinationmediated Fah gene transfer corrects the phenotype in a mouse model of human tyrosinaemia type 1(Fah-/-mice) and is long lasting in a proliferating state of the liver as shown by withdrawal of NTBC treatment and serial transplantation of isolated hepatocytes from primary Fah-/-recipient mice into secondary Fah-/-recipient mice. This long term therapeutic efficacy is clearly superior to our control mice treated with episomal r AAV8 gene therapy approach.CONCLUSION HR-mediated r AAV8 gene therapy provides targeted transgene integration and phenotypic correction in Fah-/-mice with superior long-term efficacy compared to episomal r AAV8 therapy in proliferating livers.展开更多
慢性乙型肝炎(chronic hepatitis B,CHB)是肝纤维化、肝硬化及肝细胞癌的主要风险因素。尽管目前干扰素和核苷类似物等广泛应用于临床,但仍难以彻底清除乙型肝炎病毒(hepatitis B virus,HBV),因此探究HBV感染的免疫机制,特别是宿主遗传...慢性乙型肝炎(chronic hepatitis B,CHB)是肝纤维化、肝硬化及肝细胞癌的主要风险因素。尽管目前干扰素和核苷类似物等广泛应用于临床,但仍难以彻底清除乙型肝炎病毒(hepatitis B virus,HBV),因此探究HBV感染的免疫机制,特别是宿主遗传背景的作用,对开发新治疗策略至关重要。本研究使用AAV8-rcccDNA小鼠模型,对比FVB/N×C57BL/6与DBA/2×C57BL/6两种遗传背景小鼠中HBV感染免疫反应的差异,探究了宿主遗传背景在HBV感染中的作用。结果显示,FVB/N×C57BL/6小鼠呈现免疫耐受状态,表现为持续的HBsAg表达和低HBsAb水平,而DBA/2×C57BL/6小鼠模拟了急性感染恢复状态,具体为HBsAg转阴、HBsAb阳性及病毒复制中低水平。本研究证实了在HBV感染治疗与研究中考虑宿主遗传背景差异的必要性,并指出适应性免疫系统调控在HBV治愈中的潜力,AAV8-rcccDNA小鼠模型的改进为模拟人类HBV感染免疫状态提供了有效的工具,有望助力HBV治疗策略的优化及研发。展开更多
In recent years,significant breakthroughs have been made in the field of gene ther-apy.Adeno-associated virus(AAV)is one of the most promising gene therapy vectors and a powerful tool for delivering the gene of intere...In recent years,significant breakthroughs have been made in the field of gene ther-apy.Adeno-associated virus(AAV)is one of the most promising gene therapy vectors and a powerful tool for delivering the gene of interest.Among the AAV vectors,AAV serotype 8(AAv8)has attracted much attention for its efficient and stable gene transfection into specific tissues.Currently,recombinant AAv8 has been widely used in gene therapy research on a va-riety of diseases,including genetic diseases,cancers,autoimmune diseases,and viral diseases.展开更多
基金This work was supported by the National Natural Science Foundation of China （Nos. 31071171 and 81170532） and the National High Technology Research and Development Program of China （863 Program, No. 2012AA020810）.
文摘Hemophilia B is a hemorrhagic disease caused by the deficiency of clotting factor IX （FIX）. Gene therapy might be the ultimate strategy for the disease. However, two main problems that should be solved in gene therapy for hemophilia B are immunity and safety. Self-complementary adeno-assoeiated virus serotype 8 （scAAV8）, a non-human primate AAV featuring low immunogenicity and high transfection efficiency in liver cells, might be a potential vector for hemophilia B gene therapy. A strong fiver-specific promoter-1 （LP1） was inserted and mutant human FIX Arg338Ala was introduced into plasmid scAAV8-LP1 to develop an optimized AAV8 vector that expresses human clotting factor FIX （hFIX）. The efficiency of scAAV8-LPI-hFIX administered through normal systemic injection or hydrodynamic injection was compared. A high expression was achieved using hydrodynamic injection, and the peak hFIX expression levels in the 5 × 10^11 and 1 × 10^11 virus genome （vg） cohorts were 31.94% and 25.02% of normal level, respectively, at 60 days post-injection. From the perspective of long-term （200 days） expression, both injection methods presented promising results with the concentration value maintained above 4% of normal plasma. The results were further verified by enzyme-linked immunosorbent assay and activated partial thromboplastin time. Our study provides a potential gene therapy method for hemophilia B.
基金National Science and Technology Innovation 2030 Grant(2021ZD0201003)National Natural Science Foundation of China(31830035,31771156,21921004)+2 种基金Strategic Priority Research Program of the Chinese Academy of Sciences(XDB32030200)Shenzhen Key Laboratory of Viral Vectors for Biomedicine(ZDSYS20200811142401005)Key Laboratory of Quality Control Technology for Virus-Based Therapeutics,Guangdong Provincial Medical Products Administration(2022ZDZ13)。
文摘Precise targeting of specific regions within the central nervous system(CNS)is crucial for both scientific research and gene therapy in the context of brain diseases.Adeno-associated virus 13(AAV13)is known for its restricted diffusion range within the CNS,making it an ideal choice for precise labeling and administration within small brain regions.However,AAV13 mediates relatively low expression of target genes.Here,we introduced specifically engineered modifications to the AAV13 capsid protein to enhance its transduction efficiency.We first constructed AAV13-YF by mutating tyrosine to phenylalanine on the surface of the AAV13 capsid.We then inserted the 7m8 peptide,known to enhance cell transduction,into positions 587/588 and 585/586 of the AAV13 capsid,resulting in two distinct variants named AAV13-587-7m8 and AAV13-585-7m8,respectively.We found that AAV13-YF exhibited superior in vitro infectivity in HEK293T cells compared to AAV13,while AAV13-587-7m8 and AAV13-585-7m8 showed enhanced CNS infection capabilities in C57BL/6 mice,with AAV13-587-7m8 infection retaining a limited spread range.These modified AAV13 variants hold promising potential for applications in gene therapy and neuroscience research.
基金Rebirth, SFB 738the "Deutsche Forschungsgemeinschaft" (Gerok-Grant) for financial support
文摘AIM To stably correct tyrosinaemia in proliferating livers of fumarylacetoacetate-hydrolase knockout(Fah-/-) mice by homologous-recombination-mediated targeted addition of the Fah gene.METHODS C57 BL/6 Fah?exon5 mice served as an animal model for human tyrosinaemia type 1 in our study. The vector was created by amplifying human Fah c DNA including the TTR promoter from a lentivirus plasmid as described. The Fah expression cassette was flanked by homologous arms(620 bp and 749 bp long) of the Rosa26 gene locus. Mice were injected with 2.1 × 108 VP of this vector(r AAV8-ROSA26.HAL-TTR.FahROSA26.HAR) via the tail vein. Mice in the control group were injected with 2.1 × 108 VP of a similar vector but missing the homologous arms(r AAV8-TTR.Fah). Primary hepatocytes from Fah-/-recipient mice, treated with our vectors, were isolated and 1 × 106 hepatocytes were transplanted into secondary Fah-/-recipient mice by injection into the spleen. Upon either vector application or hepatocyte transplantation NTBC treatment was stopped in recipient mice. RESULTS Here, we report successful HR-mediated genome editing by integration of a Fah gene expression cassette into the "safe harbour locus" Rosa26 by recombinant AAV8. Both groups of mice showed long-term survival, weight gain and FAH positive clusters as determined by immunohistochemistry analysis of liver sections in the absence of NTBC treatment. In the group of C57 BL/6 Fah?exon5 mice, which have been transplanted with hepatocytes from a mouse injected with r AAV8-ROSA26.HAL-TTR.Fah-ROSA26.HAR 156 d before, 6 out of 6 mice showed long-term survival, weight gain and FAH positive clusters without need for NTBC treatment. In contrast only 1 out 5 mice, who received hepatocytes from r AAV8-TTR.Fah treated mice, survived and showed few and smaller FAH positive clusters. These results demonstrate that homologous recombinationmediated Fah gene transfer corrects the phenotype in a mouse model of human tyrosinaemia type 1(Fah-/-mice) and is long lasting in a proliferating state of the liver as shown by withdrawal of NTBC treatment and serial transplantation of isolated hepatocytes from primary Fah-/-recipient mice into secondary Fah-/-recipient mice. This long term therapeutic efficacy is clearly superior to our control mice treated with episomal r AAV8 gene therapy approach.CONCLUSION HR-mediated r AAV8 gene therapy provides targeted transgene integration and phenotypic correction in Fah-/-mice with superior long-term efficacy compared to episomal r AAV8 therapy in proliferating livers.
文摘慢性乙型肝炎(chronic hepatitis B,CHB)是肝纤维化、肝硬化及肝细胞癌的主要风险因素。尽管目前干扰素和核苷类似物等广泛应用于临床,但仍难以彻底清除乙型肝炎病毒(hepatitis B virus,HBV),因此探究HBV感染的免疫机制,特别是宿主遗传背景的作用,对开发新治疗策略至关重要。本研究使用AAV8-rcccDNA小鼠模型,对比FVB/N×C57BL/6与DBA/2×C57BL/6两种遗传背景小鼠中HBV感染免疫反应的差异,探究了宿主遗传背景在HBV感染中的作用。结果显示,FVB/N×C57BL/6小鼠呈现免疫耐受状态,表现为持续的HBsAg表达和低HBsAb水平,而DBA/2×C57BL/6小鼠模拟了急性感染恢复状态,具体为HBsAg转阴、HBsAb阳性及病毒复制中低水平。本研究证实了在HBV感染治疗与研究中考虑宿主遗传背景差异的必要性,并指出适应性免疫系统调控在HBV治愈中的潜力,AAV8-rcccDNA小鼠模型的改进为模拟人类HBV感染免疫状态提供了有效的工具,有望助力HBV治疗策略的优化及研发。
文摘In recent years,significant breakthroughs have been made in the field of gene ther-apy.Adeno-associated virus(AAV)is one of the most promising gene therapy vectors and a powerful tool for delivering the gene of interest.Among the AAV vectors,AAV serotype 8(AAv8)has attracted much attention for its efficient and stable gene transfection into specific tissues.Currently,recombinant AAv8 has been widely used in gene therapy research on a va-riety of diseases,including genetic diseases,cancers,autoimmune diseases,and viral diseases.
