Objective To genetically correct a disease-causing point mutation in human induced pluripotent stem cells （iPSCs） derived from a hemophilia B patient. Methods First, the disease-causing mutation was detected by ...Objective To genetically correct a disease-causing point mutation in human induced pluripotent stem cells （iPSCs） derived from a hemophilia B patient. Methods First, the disease-causing mutation was detected by sequencing the encoding area of human coagulation factor IX （F IX） gene. Genomic DNA was extracted from the iPSCs, and the primers were designed to amplify the eight exons of F IX. Next, the point mutation in those iPSCs was genetically corrected using CRISPR/Cas9 technology in the presence of a 129-nucleotide homologous repair template that contained two synonymous mutations. Then, top 8 potential off-target sites were subsequently analyzed using Sanger sequencing. Finally, the corrected clones were differentiated into hepatocyte-like cells, and the secretion of F IX was validated by immunocytochemistry and ELISA assay.Results The cell line bore a missense mutation in the 6th coding exon （c.676 C〉T） of F IX gene. Correction of the point mutation was achieved via CRISPR/Cas9 technology in situ with a high efficacy at about 22% （10/45） and no off-target effects detected in the corrected iPSC clones. F IX secretion, which was further visualized by immunocytochemistry and quantified by ELISA in vitro, reached about 6 ng/ml on day 21 of differentiation procedure. Conclusions Mutations in human disease-specific iPSCs could be precisely corrected by CRISPR/Cas9 technology, and corrected cells still maintained hepatic differentiation capability. Our findings might throw a light on iPSC-based personalized therapies in the clinical application, especially for hemophilia B.展开更多
Patients with esophageal cancer often require esophagectomy with esophagogastrostomy.However,the incidence of complications,such as hemorrhage,during operations for esophageal cancer is high,even with minimally invasi...Patients with esophageal cancer often require esophagectomy with esophagogastrostomy.However,the incidence of complications,such as hemorrhage,during operations for esophageal cancer is high,even with minimally invasive surgery.Without the appropriate interventions,the risk of major intraoperative and postoperative hemorrhage is very high in patients with esophageal cancer and hemophilia.We report the case of a 45-year-old man with esophageal cancer and hemophilia B who underwent a successful hybrid,minimally invasive Ivor-Lewis esophagectomy with appropriate perioperative management.展开更多
Objective:Hemophilia carriers(HCs),who are heterozygous for mutations in the clotting factor VIII/clotting factor IX gene(F8 or F9),may have a wide range of clotting factor levels,from very low,similar to afflicted ma...Objective:Hemophilia carriers(HCs),who are heterozygous for mutations in the clotting factor VIII/clotting factor IX gene(F8 or F9),may have a wide range of clotting factor levels,from very low,similar to afflicted males,to the upper limit of normal,and may experience mental health issues.The purpose of this study was to provide genetic information on mothers of hemophilia patients and to understand the clotting factor activity and phenotype of HCs.Additionally,we aimed to investigate the mental health status of HCs in China.Methods:A total of 127 hemophilia mothers,including 93 hemophilia A(HA)mothers and 34 hemophilia B(HB)mothers,were enrolled in this study.Long distance PCR,multiplex PCR,and Sanger sequencing were used to analyze mutations in F8 or F9.Coagulation factor activity was detected by a one-stage clotting assay.The Symptom Checklist 90(SCL-90,China/Mandarin version)was given to HCs at the same time to assess their mental health.Results:A total of 90.6%of hemophilia mothers were diagnosed genetically as carriers,with inversion in intron 22 and missense mutations being the most common mutation types in HA and HB carriers,respectively.The median clotting factor level in carriers was 0.74 IU/mL(ranging from 0.09 to 1.74 IU/mL)compared with 1.49 IU/mL(ranging from 0.93 to 1.89 IU/mL)in noncarriers,of which 14.3%of HCs had clotting factor levels of 0.40 IU/mL or below.A total of 53.8%(7/13)of HA carriers with low clotting factor levels(less than 0.50 IU/mL)had a history of bleeding,while none of the HB carriers displayed a bleeding phenotype.The total mean score and the global severity index of the SCL-90 for surveyed HCs were 171.00(±60.37)and 1.78(±0.59),respectively.A total of 67.7%of the respondents had psychological symptoms,with obsessive-compulsive disorder being the most prevalent and severe.The pooled estimates of all nine factors were significantly higher than those in the general population(P<0.05).Conclusions:The detection rate of gene mutations in hemophilia mothers was 90.6%,with a median clotting factor level of 0.74 IU/mL,and 14.3%of HCs had a clotting factor level of 0.40 IU/mL or below.A history of bleeding was present in 41.2%of HCs with low clotting factor levels(less than 0.50 IU/mL).Additionally,given the fragile mental health status of HCs in China,it is critical to develop efficient strategies to improve psychological well-being.展开更多
A mutant human factor IX with arginine at 338 residual changed to alanine (hFIXR338A) by site-directed mutagenesis was introduced into AAV vectors, and a recombinant adeno-associ-ated viral vector containing hFIXR338A...A mutant human factor IX with arginine at 338 residual changed to alanine (hFIXR338A) by site-directed mutagenesis was introduced into AAV vectors, and a recombinant adeno-associ-ated viral vector containing hFIXR338A, prepared by rHSV/AAV hybrid helper virus system, was directly introduced to the hind leg muscle of factor IX knock out mice. The expression and the biological activity of human factor IX mutant, hFIXR338A, and the immune response against it in the treated mice were assayed and detected. The results showed that (i) the high-level expression of human factor IX mutant protein, hFIXR338A, has been detected in rAAV-hFIXR338A treated hemophilia B mice and lasted more than 15 weeks; (ii) the clotting activity of hFIXR338A in plasma is 34.2%± 5.23%, which is remarkably higher than that of (14.27%±3.4%) of wild type hFIX treated mice in the activated partial thromboplastin assay; (iii) immune response against factor IX R338A was absent, with no factor IX mutant protein (hFIXR338A) inhibitors development in the treated mice; and (iv) no local or systemic side-effects and toxicity associated with the gene transfer were found. It demonstrated the potential use of treating hemophilia B by recombinant adeho-associated viral vectors with mutant hFIXR338A gene, an alternative strategy for hemophilia B gene therapy to wild-type human factor IX.展开更多
Gene therapy provides a potential cure for hemophilia B, and significant progress has been achieved in liver-directed gene transfer mediated by adeno-associated viral vectors. Recent clinical trials involving the use ...Gene therapy provides a potential cure for hemophilia B, and significant progress has been achieved in liver-directed gene transfer mediated by adeno-associated viral vectors. Recent clinical trials involving the use of a self-complementary adeno-associated virus serotype 8-human codon-optimized factor IX （AAV8-hFIXco） vector demonstrated encouraging efficacy with hFIX expression stabilized at 1% to 6% of normal level in patients, but safety concerns related to high vector doses are still present. Thus, further improvement of AAV vectors and hFIX expression cassette may positively contribute to the ultimate success of hemophilia B gene therapy. In this study, to obtain a higher expression level of hFIX that potentiates the coagulant capacity of recipients, human FIX expression vector was optimized by upgrading the codon adaption index and adjusting the GC content, inserting a Kozak sequence （GCCACC）, and introducing a gain-of-function mutation, R338L （FIX Padua）. The efficiency of the published and the presently constructed cassettes was compared through in vivo screening. In addition, the regulatory elements that control the FIX gene expression in these cassettes were screened for liver-specific effectiveness. Among all the constructed cassettes, scAAV-Pre-hFIXco-SIH-R338L, which was the construct under the control of the prothrombin enhancer and prealbumin promoter, resulted in the highest level of coagulant activity, and the expression levels of two constructed cassettes （scAAV-Chi-hFIXco-SIH-R338L and scAAV-Pre- hFIXco-SIH-R338L） were also higher than that of the published cassette （scAAV-LPI-hFIXco-SJ）. In summary, our strategies led to a substantial increase in hFIX expression at the protein level or a remarkably elevated coagulant activity. Thus, these reconstructs of hFIX with AAV vector may potentially contribute to the creation of an efficacious gene therapy of hemophilia B.展开更多
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
CRISPR/Cas9-mediated site-specific insertion of exogenous genes holds potential for clinical applications.However,it is still infeasible because homologous recombination(HR)is inefficient,especially for nondividing ce...CRISPR/Cas9-mediated site-specific insertion of exogenous genes holds potential for clinical applications.However,it is still infeasible because homologous recombination(HR)is inefficient,especially for nondividing cells.To overcome the challenge,we report that a homology-independent targeted integration(HITI)strategy is used for permanent integration of high-specificity-activity Factor IX variant(F9 Padua,R338L)at the albumin(Alb)locus in a novel hemophilia B(HB)rat model.The knock-in efficiency reaches 3.66%,as determined by droplet digital PCR(dd PCR).The clotting time is reduced to a normal level four weeks after treatment,and the circulating factor IX(FIX)level is gradually increased up to 52%of the normal level over nine months even after partial hepatectomy,demonstrating the amelioration of hemophilia.Through primer-extension-mediated sequencing(PEM-seq),no significant off-target effect is detected.This study not only provides a novel model for HB but also identifies a promising therapeutic approach for rare inherited diseases.展开更多
Vector GtiIX containing human clotting factor IX cDNA with intron 1 (hFIX mini-gene or Fi’IX) driven by CMV promoter was constructed based on the mini-adenoviral vector GT2073 (mini-Ad vector) with all viral protein ...Vector GtiIX containing human clotting factor IX cDNA with intron 1 (hFIX mini-gene or Fi’IX) driven by CMV promoter was constructed based on the mini-adenoviral vector GT2073 (mini-Ad vector) with all viral protein coding sequences deleted. Mini-Ad packaging cell 293Cre4 was first transduced with GTiIX, and then was transfected with helper-adenovirus AdLC8, thus mini-Ad virions AdGTiIX were obtained. At the same time, previous normal adenoviral vector pAdSPiIX containing viral genome and hFIX mini-gene was constructed, and then previous ade-novirus (pre-Ad) AdSPiIX was obtained as control. The ratio of helper-adenovirus among purified virons AdGTiIX was less than 0.8%. 3T3 cells were transfected with AdGTiIX and AdSPiIX at a MOI of 50 per cell and ELISA result showed that transient expression level in vitro was 1.4±0.2 mg /106·24 h and 1.6±0.3 mg/106·24 h respectively. Each hemophilia B (FIX knock-out) mouse received celiac injection of 11010pfu AdGTiIX or AdSPiIX. The highest expression level of hFIX in mouse plasma was 590 ng/mL and 690 ng/mL respectively, and the expression time lasted for 16 weeks and 9 weeks respectively. The bleeding time reduced from over 30 min to 7.5 min, and 5-min blood lost reduced from 430 mL to 60 mL. The results of anti-Ad IgG assays indicated that immune response triggered by AdGTiIX was obviously weaker than that triggered by AdSPiIX. These results indicated that, compared with previous adenovirus (pre-Ad), the mini-Ad vector sys-tem prolonged the expression time of hFIX and reduced immune response, thus offering a prom-ising result for further pre-clinical study.展开更多
To explore the expression of human clotting factor Ⅸ (hFⅨ) cDNA in vitro and the feasibility of gene therapy for hemophilia B mice mediated by recombinant lentiviral vector, a recombinant hFⅨ lentiviral vector driv...To explore the expression of human clotting factor Ⅸ (hFⅨ) cDNA in vitro and the feasibility of gene therapy for hemophilia B mice mediated by recombinant lentiviral vector, a recombinant hFⅨ lentiviral vector driven by ubiquitin-C promoter, FUXW, and by ABP liver specific promoter, FAXW, was constructed respectively. Recombinant lentivirus was harvested from 293T cells by calcium phosphate-mediated transient cotransfection of three plasmids (transgene vector, CMV腞8.2, VSV-G). hFⅨ expression was detected in supernatant of 293T, BHK and L-02 cells infected with FUXW virus, whereas higher expression of hFⅨ levels (630 ng/106 cells/48 h) was detected only in L-02 cells infected with FAXW virus. Serum hFⅨ antigen was detected in all hemophilia B mice treated with FAXW virus by tail vein injection, an efficiency level of hFⅨ was observed (45 ng/mL, approximately 1% of normal human levels), the expression lasted for more than 60 d. The results indicated that HIV-based lentiviral vectors offer a promising approach to the gene therapy of hemophilia B.展开更多
Recombinant AAV particles of high titer (>1013 virus genome/mL) were prepared according to the rHSV/AAV helper virus method. After intramuscular injection of viral vectors in the hind limb, a sustained elevated lev...Recombinant AAV particles of high titer (>1013 virus genome/mL) were prepared according to the rHSV/AAV helper virus method. After intramuscular injection of viral vectors in the hind limb, a sustained elevated level (>370 ng/mL) of murine FIX expression in the plasma of hemophilia B mouse was detected and persisted for more than 350 days. The biological activity reached 30% of normal levels, and bleeding symptoms in the treated mice were significantly alleviated. No anti-FIX antibody (inhibitor) was detected, though anti-AAV antibodies were found at a very low level after single injection. Repeated injection with rAAV/mFIX led to a variation in anti-AAV antibody levels between the two groups which had received different doses. Results from tissue analysis confirmed the skeletal muscle as the origin for circulating functional mFIX. Our results suggest that AAV-mediated gene transfer offers a promising method of gene therapy for hemophilia B.展开更多
世界血友病同盟(World Federation of Hemophilia,WFH)于2022年10月发布了新的年度血友病全球报告(Annual Global Survey,AGS)(以下简称AGS 2022),提出了新的工作目标。在2025年前,提高识别并诊断遗传性出血性疾病能力,包括:在原有基础...世界血友病同盟(World Federation of Hemophilia,WFH)于2022年10月发布了新的年度血友病全球报告(Annual Global Survey,AGS)(以下简称AGS 2022),提出了新的工作目标。在2025年前,提高识别并诊断遗传性出血性疾病能力,包括:在原有基础性上,提高25%的血友病确诊率和14%的血管性血友病(von Willebrand disease,vWD)患者确诊率;提供合适的护理和治疗,特别是要提高25%的18岁以下重型血友病患者预防治疗率,继续每年至少为20000例患者提供WFH人道主义援助。AGS 2022预估了全球的血友病年平均患病率:血友病A(hemophilia A,HA)为17.1/10万(男性),其中重型HA为6.0/10万(男性);血友病B(hemophilia B,HB)为3.8/10万(男性),其中重型HB为1.1/10万男性。根据世界人口(79亿,40亿男性),预计全球血友病患病率在10.6/10万左右,预计全球有血友病患者830895例,其中约282266例为重型患者。我国的血友病患病率在(2.73~3.09)/10万,低于全球水平。同时,AGS 2022提示,全球女性血友病患者有11700例,女性血友病占血友病患者总人数的5%;女性vWD患者有54066例,占vWD总人数的56%,女性其他出血性疾病有34370例,提示vWD是女性最常见的出血性疾病。我国的HA患者共27689例,其中0~4岁占4%,5~13岁占21%,14~18岁占12%,19~44岁占43%,45岁以上占16%,年龄不确定者占4%。相对于中低收入国家,高收入国家对于轻型血友病的确诊率高(男性40%比12%;女性86%比23%),不确定性患者比例少,而低收入国家的血友病患者早逝风险很大。经济发达地区的艾美赛珠单抗预防治疗使用显著高于我国。我国相较于欧美国家在血友病及其他出血性疾病患者的诊断及治疗方面还有较大差距,临床医务工作者需提高对血友病及其他出血性疾病的认识并不断提高诊断和治疗能力。展开更多
基金Supported by the National Science and Technology Major Project(2011ZX09102-010-04)
文摘Objective To genetically correct a disease-causing point mutation in human induced pluripotent stem cells （iPSCs） derived from a hemophilia B patient. Methods First, the disease-causing mutation was detected by sequencing the encoding area of human coagulation factor IX （F IX） gene. Genomic DNA was extracted from the iPSCs, and the primers were designed to amplify the eight exons of F IX. Next, the point mutation in those iPSCs was genetically corrected using CRISPR/Cas9 technology in the presence of a 129-nucleotide homologous repair template that contained two synonymous mutations. Then, top 8 potential off-target sites were subsequently analyzed using Sanger sequencing. Finally, the corrected clones were differentiated into hepatocyte-like cells, and the secretion of F IX was validated by immunocytochemistry and ELISA assay.Results The cell line bore a missense mutation in the 6th coding exon （c.676 C〉T） of F IX gene. Correction of the point mutation was achieved via CRISPR/Cas9 technology in situ with a high efficacy at about 22% （10/45） and no off-target effects detected in the corrected iPSC clones. F IX secretion, which was further visualized by immunocytochemistry and quantified by ELISA in vitro, reached about 6 ng/ml on day 21 of differentiation procedure. Conclusions Mutations in human disease-specific iPSCs could be precisely corrected by CRISPR/Cas9 technology, and corrected cells still maintained hepatic differentiation capability. Our findings might throw a light on iPSC-based personalized therapies in the clinical application, especially for hemophilia B.
文摘Patients with esophageal cancer often require esophagectomy with esophagogastrostomy.However,the incidence of complications,such as hemorrhage,during operations for esophageal cancer is high,even with minimally invasive surgery.Without the appropriate interventions,the risk of major intraoperative and postoperative hemorrhage is very high in patients with esophageal cancer and hemophilia.We report the case of a 45-year-old man with esophageal cancer and hemophilia B who underwent a successful hybrid,minimally invasive Ivor-Lewis esophagectomy with appropriate perioperative management.
基金supported by Pfizer and the Haemophilia,Experience,Results,and Opportunities(HERO)Research Grant(Novo Nordisk).
文摘Objective:Hemophilia carriers(HCs),who are heterozygous for mutations in the clotting factor VIII/clotting factor IX gene(F8 or F9),may have a wide range of clotting factor levels,from very low,similar to afflicted males,to the upper limit of normal,and may experience mental health issues.The purpose of this study was to provide genetic information on mothers of hemophilia patients and to understand the clotting factor activity and phenotype of HCs.Additionally,we aimed to investigate the mental health status of HCs in China.Methods:A total of 127 hemophilia mothers,including 93 hemophilia A(HA)mothers and 34 hemophilia B(HB)mothers,were enrolled in this study.Long distance PCR,multiplex PCR,and Sanger sequencing were used to analyze mutations in F8 or F9.Coagulation factor activity was detected by a one-stage clotting assay.The Symptom Checklist 90(SCL-90,China/Mandarin version)was given to HCs at the same time to assess their mental health.Results:A total of 90.6%of hemophilia mothers were diagnosed genetically as carriers,with inversion in intron 22 and missense mutations being the most common mutation types in HA and HB carriers,respectively.The median clotting factor level in carriers was 0.74 IU/mL(ranging from 0.09 to 1.74 IU/mL)compared with 1.49 IU/mL(ranging from 0.93 to 1.89 IU/mL)in noncarriers,of which 14.3%of HCs had clotting factor levels of 0.40 IU/mL or below.A total of 53.8%(7/13)of HA carriers with low clotting factor levels(less than 0.50 IU/mL)had a history of bleeding,while none of the HB carriers displayed a bleeding phenotype.The total mean score and the global severity index of the SCL-90 for surveyed HCs were 171.00(±60.37)and 1.78(±0.59),respectively.A total of 67.7%of the respondents had psychological symptoms,with obsessive-compulsive disorder being the most prevalent and severe.The pooled estimates of all nine factors were significantly higher than those in the general population(P<0.05).Conclusions:The detection rate of gene mutations in hemophilia mothers was 90.6%,with a median clotting factor level of 0.74 IU/mL,and 14.3%of HCs had a clotting factor level of 0.40 IU/mL or below.A history of bleeding was present in 41.2%of HCs with low clotting factor levels(less than 0.50 IU/mL).Additionally,given the fragile mental health status of HCs in China,it is critical to develop efficient strategies to improve psychological well-being.
基金the State High Technology Development Program (Grant No.Z20-02-01), Shanghai Post-doctoral Fellowship Foundation the National "863" High-Tech Program+1 种基金 the National Natural Science Foundation of China (Grant No. 39880019) Fok Ying Tung Foundation (Gra
文摘A mutant human factor IX with arginine at 338 residual changed to alanine (hFIXR338A) by site-directed mutagenesis was introduced into AAV vectors, and a recombinant adeno-associ-ated viral vector containing hFIXR338A, prepared by rHSV/AAV hybrid helper virus system, was directly introduced to the hind leg muscle of factor IX knock out mice. The expression and the biological activity of human factor IX mutant, hFIXR338A, and the immune response against it in the treated mice were assayed and detected. The results showed that (i) the high-level expression of human factor IX mutant protein, hFIXR338A, has been detected in rAAV-hFIXR338A treated hemophilia B mice and lasted more than 15 weeks; (ii) the clotting activity of hFIXR338A in plasma is 34.2%± 5.23%, which is remarkably higher than that of (14.27%±3.4%) of wild type hFIX treated mice in the activated partial thromboplastin assay; (iii) immune response against factor IX R338A was absent, with no factor IX mutant protein (hFIXR338A) inhibitors development in the treated mice; and (iv) no local or systemic side-effects and toxicity associated with the gene transfer were found. It demonstrated the potential use of treating hemophilia B by recombinant adeho-associated viral vectors with mutant hFIXR338A gene, an alternative strategy for hemophilia B gene therapy to wild-type human factor IX.
文摘Gene therapy provides a potential cure for hemophilia B, and significant progress has been achieved in liver-directed gene transfer mediated by adeno-associated viral vectors. Recent clinical trials involving the use of a self-complementary adeno-associated virus serotype 8-human codon-optimized factor IX （AAV8-hFIXco） vector demonstrated encouraging efficacy with hFIX expression stabilized at 1% to 6% of normal level in patients, but safety concerns related to high vector doses are still present. Thus, further improvement of AAV vectors and hFIX expression cassette may positively contribute to the ultimate success of hemophilia B gene therapy. In this study, to obtain a higher expression level of hFIX that potentiates the coagulant capacity of recipients, human FIX expression vector was optimized by upgrading the codon adaption index and adjusting the GC content, inserting a Kozak sequence （GCCACC）, and introducing a gain-of-function mutation, R338L （FIX Padua）. The efficiency of the published and the presently constructed cassettes was compared through in vivo screening. In addition, the regulatory elements that control the FIX gene expression in these cassettes were screened for liver-specific effectiveness. Among all the constructed cassettes, scAAV-Pre-hFIXco-SIH-R338L, which was the construct under the control of the prothrombin enhancer and prealbumin promoter, resulted in the highest level of coagulant activity, and the expression levels of two constructed cassettes （scAAV-Chi-hFIXco-SIH-R338L and scAAV-Pre- hFIXco-SIH-R338L） were also higher than that of the published cassette （scAAV-LPI-hFIXco-SJ）. In summary, our strategies led to a substantial increase in hFIX expression at the protein level or a remarkably elevated coagulant activity. Thus, these reconstructs of hFIX with AAV vector may potentially contribute to the creation of an efficacious gene therapy of hemophilia B.
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supported by grants from National Key R&D Program of China(2019YFA0110802 and 2019YFA0802800)the National Natural Science Foundation of China(32025023,31971366)+1 种基金grants from the Shanghai Municipal Commission for Science and Technology(21CJ1402200,20140900200)the Innovation Program of Shanghai Municipal Education Commission(2019-01-07-00-05-E00054)。
文摘CRISPR/Cas9-mediated site-specific insertion of exogenous genes holds potential for clinical applications.However,it is still infeasible because homologous recombination(HR)is inefficient,especially for nondividing cells.To overcome the challenge,we report that a homology-independent targeted integration(HITI)strategy is used for permanent integration of high-specificity-activity Factor IX variant(F9 Padua,R338L)at the albumin(Alb)locus in a novel hemophilia B(HB)rat model.The knock-in efficiency reaches 3.66%,as determined by droplet digital PCR(dd PCR).The clotting time is reduced to a normal level four weeks after treatment,and the circulating factor IX(FIX)level is gradually increased up to 52%of the normal level over nine months even after partial hepatectomy,demonstrating the amelioration of hemophilia.Through primer-extension-mediated sequencing(PEM-seq),no significant off-target effect is detected.This study not only provides a novel model for HB but also identifies a promising therapeutic approach for rare inherited diseases.
基金supported by the State High Technology Development Program(863).
文摘Vector GtiIX containing human clotting factor IX cDNA with intron 1 (hFIX mini-gene or Fi’IX) driven by CMV promoter was constructed based on the mini-adenoviral vector GT2073 (mini-Ad vector) with all viral protein coding sequences deleted. Mini-Ad packaging cell 293Cre4 was first transduced with GTiIX, and then was transfected with helper-adenovirus AdLC8, thus mini-Ad virions AdGTiIX were obtained. At the same time, previous normal adenoviral vector pAdSPiIX containing viral genome and hFIX mini-gene was constructed, and then previous ade-novirus (pre-Ad) AdSPiIX was obtained as control. The ratio of helper-adenovirus among purified virons AdGTiIX was less than 0.8%. 3T3 cells were transfected with AdGTiIX and AdSPiIX at a MOI of 50 per cell and ELISA result showed that transient expression level in vitro was 1.4±0.2 mg /106·24 h and 1.6±0.3 mg/106·24 h respectively. Each hemophilia B (FIX knock-out) mouse received celiac injection of 11010pfu AdGTiIX or AdSPiIX. The highest expression level of hFIX in mouse plasma was 590 ng/mL and 690 ng/mL respectively, and the expression time lasted for 16 weeks and 9 weeks respectively. The bleeding time reduced from over 30 min to 7.5 min, and 5-min blood lost reduced from 430 mL to 60 mL. The results of anti-Ad IgG assays indicated that immune response triggered by AdGTiIX was obviously weaker than that triggered by AdSPiIX. These results indicated that, compared with previous adenovirus (pre-Ad), the mini-Ad vector sys-tem prolonged the expression time of hFIX and reduced immune response, thus offering a prom-ising result for further pre-clinical study.
文摘To explore the expression of human clotting factor Ⅸ (hFⅨ) cDNA in vitro and the feasibility of gene therapy for hemophilia B mice mediated by recombinant lentiviral vector, a recombinant hFⅨ lentiviral vector driven by ubiquitin-C promoter, FUXW, and by ABP liver specific promoter, FAXW, was constructed respectively. Recombinant lentivirus was harvested from 293T cells by calcium phosphate-mediated transient cotransfection of three plasmids (transgene vector, CMV腞8.2, VSV-G). hFⅨ expression was detected in supernatant of 293T, BHK and L-02 cells infected with FUXW virus, whereas higher expression of hFⅨ levels (630 ng/106 cells/48 h) was detected only in L-02 cells infected with FAXW virus. Serum hFⅨ antigen was detected in all hemophilia B mice treated with FAXW virus by tail vein injection, an efficiency level of hFⅨ was observed (45 ng/mL, approximately 1% of normal human levels), the expression lasted for more than 60 d. The results indicated that HIV-based lentiviral vectors offer a promising approach to the gene therapy of hemophilia B.
基金supported by the National“863”High-tech Program(Grant No.2001AA217181)the National Natural Science Foundation of China(Grant No.39880019)+3 种基金Foundation of Doctor Degree Thesis from the Ministry of Education of China(Grant No.199925)Doctor Degree Spot of the Ministry of Education(Grant No.98024620)Fok Yingtung Foundation(Grant No.71019),JRAPOYTFoundation of Cross-Century Personnel from Ministry of Education of China.
文摘Recombinant AAV particles of high titer (>1013 virus genome/mL) were prepared according to the rHSV/AAV helper virus method. After intramuscular injection of viral vectors in the hind limb, a sustained elevated level (>370 ng/mL) of murine FIX expression in the plasma of hemophilia B mouse was detected and persisted for more than 350 days. The biological activity reached 30% of normal levels, and bleeding symptoms in the treated mice were significantly alleviated. No anti-FIX antibody (inhibitor) was detected, though anti-AAV antibodies were found at a very low level after single injection. Repeated injection with rAAV/mFIX led to a variation in anti-AAV antibody levels between the two groups which had received different doses. Results from tissue analysis confirmed the skeletal muscle as the origin for circulating functional mFIX. Our results suggest that AAV-mediated gene transfer offers a promising method of gene therapy for hemophilia B.
