Double-copy retroviral vector containing human factor Ⅸ cDNA driven by human cytomegalovirus enhancer-promoter was constructed. The vector was introduced into the amphotropic packaging cell line PA317. The recombinan...Double-copy retroviral vector containing human factor Ⅸ cDNA driven by human cytomegalovirus enhancer-promoter was constructed. The vector was introduced into the amphotropic packaging cell line PA317. The recombinant virus produced in PA317 was used to transduce skin fibroblasts from a hemophilia B patient. The infected cells produced high levels of biologically active human factor Ⅸ at a rate of 3420 ng/10~6 cells/24 h. These cells were embedded in a collagen matrix and implanted into the peritoneal cavity or subcutaneous space of mice. It was demonstrated that human factor Ⅸ was produced by the implants for at least 12 days in vivo, reaching a peak of 105 ng/ml plasma. Over 90% of the protein was functionally active. This technique has the potential to be developed into a new approach for gene therapy for hemophilia B.展开更多
To study the possibility of somatic gene therapy for hemophilia B via gene transfer to primary factor Ⅸ-deficient skin fibroblasts, we constructed four retroviral vectors containing factor Ⅸ cDNA driven by retrovira...To study the possibility of somatic gene therapy for hemophilia B via gene transfer to primary factor Ⅸ-deficient skin fibroblasts, we constructed four retroviral vectors containing factor Ⅸ cDNA driven by retroviral LTR promoter, SV40 early promoter and mouse MT-I promoter, respectively. These retroviral vectors were transfected into an amphotropic packaging cell line, PA317 cells, by electroporation, and a human iibrosarcoma cell line, HT1080 cells, was used to assay the factor Ⅸ-virus titers of these four virus-producing PA317 cells, which ranged from 2×10~4 to 5×10~5 cfu/ml. The factor Ⅸ proteins produced by bulk population of four virus-producing PA317 cells were determined by ELISA. Results showed that LTR promoter directed the highest production of factor Ⅸ at the rate of 584 rig/10~6 cells/24h, while SV40 early promoter and MT promoter directed about 10 and 20 times less production of factor Ⅸ than LTR promoter. The highest expressed retroviral vector XL-Ⅸ was used to infect a line of展开更多
THE mammary gland bioreactor system of lactating animal, established by germ-linemicroinjection and embryo transplantation, has been one of the most exciting projects in thefield of biotechnology. However, this system...THE mammary gland bioreactor system of lactating animal, established by germ-linemicroinjection and embryo transplantation, has been one of the most exciting projects in thefield of biotechnology. However, this system is costly, laborious and tim-cosuming. In 1994,Johanna et al. reported that secretion of a foreign protein, human growth hormone (hGH),in milk had been achieved after direct introduction of the cDNA into the mammary gland ofgoats by replication-defective retroviral vector. In that work, the in vivo expression of展开更多
Hemophilia B is an inherited bleeding disorder due to a deficiency of factor Ⅸ.Currently, conventional therapy depends on the infusion of human plasma or factor Ⅸ concentrate. The therapeutic effect is temporary and...Hemophilia B is an inherited bleeding disorder due to a deficiency of factor Ⅸ.Currently, conventional therapy depends on the infusion of human plasma or factor Ⅸ concentrate. The therapeutic effect is temporary and periodic infusions are required. This approach of treatment is expensive, and is associated with a significant risk of AIDS and hepatitis. Recent advances in gene-transfer techniques have provided a new approach of therapy for genetic diseases, including factor Ⅸ deficiency. Previously, we constructed sev-展开更多
In this study, rabbits were used as a model for gene therapy for hemophilia B, Human factor Ⅸ cDNA was transferred to cultured normal rabbit skin fibroblasts (RSF) by a recombinant plasmid (pCMVIX) or retrovirus(XL-I...In this study, rabbits were used as a model for gene therapy for hemophilia B, Human factor Ⅸ cDNA was transferred to cultured normal rabbit skin fibroblasts (RSF) by a recombinant plasmid (pCMVIX) or retrovirus(XL-IX or N2CMVIX) constructed in our laboratoy. Infected fibroblasts capable of synthesizing and secreting high levels of biologically active human factor Ⅸ protein were selected and embedded in a collagen matrix. The latter was surgically implanted into rabbits as autografts or allografts. Human factor Ⅸ protein was detected in the plasma of all the grafted rabbits, and its expression has been maintained for more than 10 months at the time of writing. In addition, we have improved and simplified the method of implantation from surgically grafting the tissue-like matrix to the injection of the infected cell-collagen mixture subcutaneously. Using the latter method, human factor Ⅸ in rabbits injected with RSF-N2CMVIX reached a peak of 480 ng/ml plasma, and its expression has continued for展开更多
目的 :探讨人凝血因子 (F )内含子 1片段正向插入逆转录病毒载体对骨骼肌细胞表达 F 的影响。 方法 :将含F 内含子 1片段的 F 微小基因 m 1和 m 2正向插入 L SN逆转录病毒载体的 Bam H 位点 ,取代 F c DNA,获得 m 1SN和 L m 2 SN载...目的 :探讨人凝血因子 (F )内含子 1片段正向插入逆转录病毒载体对骨骼肌细胞表达 F 的影响。 方法 :将含F 内含子 1片段的 F 微小基因 m 1和 m 2正向插入 L SN逆转录病毒载体的 Bam H 位点 ,取代 F c DNA,获得 m 1SN和 L m 2 SN载体 ,在小鼠成肌细胞进行瞬时和稳定表达试验。结果 :L m 1SN的 m 2 SN载体的病毒滴度、在成肌细胞中瞬时表达和稳定表达 F 的水平 ,均比不含内含子的 L SN增高 1～ 2倍 ,小部分病毒 RNA中的内含子在包装细胞中未被剪接去除而转入了靶细胞。结论 :人 F 内含子 1片段正向插入逆转录病毒载体对提高病毒滴度和 F 的表达水平有一定作用。展开更多
文摘Double-copy retroviral vector containing human factor Ⅸ cDNA driven by human cytomegalovirus enhancer-promoter was constructed. The vector was introduced into the amphotropic packaging cell line PA317. The recombinant virus produced in PA317 was used to transduce skin fibroblasts from a hemophilia B patient. The infected cells produced high levels of biologically active human factor Ⅸ at a rate of 3420 ng/10~6 cells/24 h. These cells were embedded in a collagen matrix and implanted into the peritoneal cavity or subcutaneous space of mice. It was demonstrated that human factor Ⅸ was produced by the implants for at least 12 days in vivo, reaching a peak of 105 ng/ml plasma. Over 90% of the protein was functionally active. This technique has the potential to be developed into a new approach for gene therapy for hemophilia B.
基金This work was supported by a grant from the State High Technology Development Program 863-102-17-40
文摘To study the possibility of somatic gene therapy for hemophilia B via gene transfer to primary factor Ⅸ-deficient skin fibroblasts, we constructed four retroviral vectors containing factor Ⅸ cDNA driven by retroviral LTR promoter, SV40 early promoter and mouse MT-I promoter, respectively. These retroviral vectors were transfected into an amphotropic packaging cell line, PA317 cells, by electroporation, and a human iibrosarcoma cell line, HT1080 cells, was used to assay the factor Ⅸ-virus titers of these four virus-producing PA317 cells, which ranged from 2×10~4 to 5×10~5 cfu/ml. The factor Ⅸ proteins produced by bulk population of four virus-producing PA317 cells were determined by ELISA. Results showed that LTR promoter directed the highest production of factor Ⅸ at the rate of 584 rig/10~6 cells/24h, while SV40 early promoter and MT promoter directed about 10 and 20 times less production of factor Ⅸ than LTR promoter. The highest expressed retroviral vector XL-Ⅸ was used to infect a line of
文摘THE mammary gland bioreactor system of lactating animal, established by germ-linemicroinjection and embryo transplantation, has been one of the most exciting projects in thefield of biotechnology. However, this system is costly, laborious and tim-cosuming. In 1994,Johanna et al. reported that secretion of a foreign protein, human growth hormone (hGH),in milk had been achieved after direct introduction of the cDNA into the mammary gland ofgoats by replication-defective retroviral vector. In that work, the in vivo expression of
基金Project supported by the National High Technology Program
文摘Hemophilia B is an inherited bleeding disorder due to a deficiency of factor Ⅸ.Currently, conventional therapy depends on the infusion of human plasma or factor Ⅸ concentrate. The therapeutic effect is temporary and periodic infusions are required. This approach of treatment is expensive, and is associated with a significant risk of AIDS and hepatitis. Recent advances in gene-transfer techniques have provided a new approach of therapy for genetic diseases, including factor Ⅸ deficiency. Previously, we constructed sev-
文摘In this study, rabbits were used as a model for gene therapy for hemophilia B, Human factor Ⅸ cDNA was transferred to cultured normal rabbit skin fibroblasts (RSF) by a recombinant plasmid (pCMVIX) or retrovirus(XL-IX or N2CMVIX) constructed in our laboratoy. Infected fibroblasts capable of synthesizing and secreting high levels of biologically active human factor Ⅸ protein were selected and embedded in a collagen matrix. The latter was surgically implanted into rabbits as autografts or allografts. Human factor Ⅸ protein was detected in the plasma of all the grafted rabbits, and its expression has been maintained for more than 10 months at the time of writing. In addition, we have improved and simplified the method of implantation from surgically grafting the tissue-like matrix to the injection of the infected cell-collagen mixture subcutaneously. Using the latter method, human factor Ⅸ in rabbits injected with RSF-N2CMVIX reached a peak of 480 ng/ml plasma, and its expression has continued for
文摘目的 :探讨人凝血因子 (F )内含子 1片段正向插入逆转录病毒载体对骨骼肌细胞表达 F 的影响。 方法 :将含F 内含子 1片段的 F 微小基因 m 1和 m 2正向插入 L SN逆转录病毒载体的 Bam H 位点 ,取代 F c DNA,获得 m 1SN和 L m 2 SN载体 ,在小鼠成肌细胞进行瞬时和稳定表达试验。结果 :L m 1SN的 m 2 SN载体的病毒滴度、在成肌细胞中瞬时表达和稳定表达 F 的水平 ,均比不含内含子的 L SN增高 1～ 2倍 ,小部分病毒 RNA中的内含子在包装细胞中未被剪接去除而转入了靶细胞。结论 :人 F 内含子 1片段正向插入逆转录病毒载体对提高病毒滴度和 F 的表达水平有一定作用。
