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Liu L, Xu B, Chen L, Liu J, Liu W, Xue F, Feng S, Jiang E, Han M, Shao W, Zhang L, Pei X. An investigation of the immune epitopes of adeno-associated virus capsid-derived peptides among hemophilia patients. Mol Ther Methods Clin Dev 2024; 32:101245. [PMID: 38660620 PMCID: PMC11039395 DOI: 10.1016/j.omtm.2024.101245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Accepted: 03/29/2024] [Indexed: 04/26/2024]
Abstract
Adeno-associated virus (AAV) is an optimal gene vector for monogenic disorders. However, neutralizing antibodies (Nabs) against AAV hinder its widespread application in gene therapy. In this study, we biosynthesized peptides recognized by the binding antibodies (Babs) from the sera containing high Nab titers against AAV2. We established four immunological methods to detect immune epitopes of the AAV2-derived peptides, including a Bab assay, Nab assay, B cell receptor (BCR) detecting assay, and immunoglobin-producing B cell enzyme-linked immunosorbent spot (B cell ELISpot) assay. Correlations among the epitopes determined by these four methods were analyzed using the serum samples and peripheral blood mononuclear cells (PBMC) from 89 patients with hemophilia A/B. As decoys, the peptides' ability to block the Nab of AAV2 particles was assessed using AAV transduction models both in vitro and in vivo. Overall, we provide insights into AAV2-capsid-derived peptide immune epitopes, involving the Nab, Bab, BCR, and B cell ELISpot assays, offering alternative immunological evaluation approaches and strategies to overcome Nab barriers in AAV-mediated gene therapy.
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Affiliation(s)
- Li Liu
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, P.R. China
- Tianjin Institutes of Health Science, Tianjin 300020, P.R. China
| | - Bingqi Xu
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, P.R. China
- Tianjin Institutes of Health Science, Tianjin 300020, P.R. China
| | - Lingling Chen
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, P.R. China
- Tianjin Institutes of Health Science, Tianjin 300020, P.R. China
| | - Jia Liu
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, P.R. China
- Tianjin Institutes of Health Science, Tianjin 300020, P.R. China
| | - Wei Liu
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, P.R. China
- Tianjin Institutes of Health Science, Tianjin 300020, P.R. China
| | - Feng Xue
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, P.R. China
- Tianjin Institutes of Health Science, Tianjin 300020, P.R. China
| | - Sizhou Feng
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, P.R. China
- Tianjin Institutes of Health Science, Tianjin 300020, P.R. China
| | - Erlie Jiang
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, P.R. China
- Tianjin Institutes of Health Science, Tianjin 300020, P.R. China
| | - Mingzhe Han
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, P.R. China
- Tianjin Institutes of Health Science, Tianjin 300020, P.R. China
| | - Wenwei Shao
- Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin 300072, P.R. China
| | - Lei Zhang
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, P.R. China
- Tianjin Institutes of Health Science, Tianjin 300020, P.R. China
| | - Xiaolei Pei
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, P.R. China
- Tianjin Institutes of Health Science, Tianjin 300020, P.R. China
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2
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Rana J, Marsic D, Zou C, Muñoz-Melero M, Li X, Kondratov O, Li N, de Jong YP, Zolotukhin S, Biswas M. Characterization of a Bioengineered AAV3B Capsid Variant with Enhanced Hepatocyte Tropism and Immune Evasion. Hum Gene Ther 2023; 34:289-302. [PMID: 36950804 PMCID: PMC10125406 DOI: 10.1089/hum.2022.176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2022] [Accepted: 02/25/2023] [Indexed: 03/24/2023] Open
Abstract
Capsid engineering of adeno-associated virus (AAV) can surmount current limitations to gene therapy such as broad tissue tropism, low transduction efficiency, or pre-existing neutralizing antibodies (NAb) that restrict patient eligibility. We previously generated an AAV3B combinatorial capsid library by integrating rational design and directed evolution with the aim of improving hepatotropism. A potential isolate, AAV3B-DE5, gained a selective proliferative advantage over five rounds of iterative selection in hepatocyte spheroid cultures. In this study, we reanalyzed our original dataset derived from the AAV3B combinatorial library and isolated variants from earlier (one to three) rounds of selection, with the assumption that variants with faster replication kinetics are not necessarily the most efficient transducers. We identified a potential candidate, AAV3B-V04, which demonstrated significantly enhanced transduction in mouse-passaged primary human hepatocytes as well as in humanized liver chimeric mice, compared to the parental AAV3B or the previously described isolate, AAV3B-DE5. Interestingly, the AAV3B-V04 capsid variant exhibited significantly reduced seroreactivity to pooled or individual human serum samples. Forty-four percent of serum samples with pre-existing NAbs to AAV3B had 5- to 20-fold lower reciprocal NAb titers to AAV3B-V04. AAV3B-V04 has only nine amino acid substitutions, clustered in variable region IV compared to AAV3B, indicating the importance of the loops at the top of the three-fold protrusions in determining both transduction efficiency and immunogenicity. This study highlights the effectiveness of rational design combined with targeted selection for enhanced AAV transduction via molecular evolution approaches. Our findings support the concept of limiting selection rounds to isolate the best transducing AAV3B variant without outgrowth of faster replicating candidates. We conclude that AAV3B-V04 provides advantages such as improved human hepatocyte tropism and immune evasion and propose its utility as a superior candidate for liver gene therapy.
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Affiliation(s)
- Jyoti Rana
- Herman B Wells Center for Pediatric Research, Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Damien Marsic
- Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida, Gainesville, Florida, USA
- Porton Biologics, Jiangsu, China
| | - Chenhui Zou
- Division of Gastroenterology and Hepatology, Weill Cornell Medicine, New York, New York, USA
- Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, New York, USA
| | - Maite Muñoz-Melero
- Herman B Wells Center for Pediatric Research, Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Xin Li
- Herman B Wells Center for Pediatric Research, Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Oleksandr Kondratov
- Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida, Gainesville, Florida, USA
| | - Ning Li
- Herman B Wells Center for Pediatric Research, Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Ype P. de Jong
- Division of Gastroenterology and Hepatology, Weill Cornell Medicine, New York, New York, USA
- Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, New York, USA
| | - Sergei Zolotukhin
- Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida, Gainesville, Florida, USA
| | - Moanaro Biswas
- Herman B Wells Center for Pediatric Research, Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, USA
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Prevalence of Neutralizing Antibodies against Adeno-Associated Virus Serotypes 1, 2, and 9 in Non-Injected Latin American Patients with Heart Failure—ANVIAS Study. Int J Mol Sci 2023; 24:ijms24065579. [PMID: 36982654 PMCID: PMC10051173 DOI: 10.3390/ijms24065579] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 01/24/2023] [Accepted: 01/25/2023] [Indexed: 03/17/2023] Open
Abstract
Neutralizing antibody (NAb) activity against the viral capsid of adeno-associated viral (AAV) vectors decreases transduction efficiency, thus limiting transgene expression. Several reports have mentioned a variation in NAb prevalence according to age, AAV serotype, and, most importantly, geographic location. There are currently no reports specifically describing the anti-AAV NAb prevalence in Latin America. Here, we describe the prevalence of NAb against different serotypes of AAV vectors (AAV1, AAV2, and AAV9) in Colombian patients with heart failure (HF) (referred to as cases) and healthy individuals (referred to as controls). The levels of NAb were evaluated in serum samples of 60 subjects from each group using an in vitro inhibitory assay. The neutralizing titer was reported as the first dilution inhibiting ≥50% of the transgene signal, and the samples with neutralizing titers at ≥1:50 dilution were considered positive. The prevalence of NAb in the case and control groups were similar (AAV2: 43% and 45%, respectively; AAV1 33.3% in each group; AAV9: 20% and 23.2%, respectively). The presence of NAb for two or more of the serotypes analyzed was observed in 25% of the studied samples, with the largest amount in the positive samples for AAV1 (55–75%) and AAV9 (93%), suggesting serial exposures, cross-reactivity, or coinfection. Moreover, patients in the HF group exhibited more common combined seropositivity for NAb against AAV1 d AAV9 than those in the control group (91.6% vs. 35.7%, respectively; p = 0.003). Finally, exposure to toxins was significantly associated with the presence of NAb in all regression models. These results constitute the first report of the prevalence of NAb against AAV in Latin America, being the first step to implementing therapeutic strategies based on AAV vectors in this population in our region.
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Kuoch H, Krotova K, Graham ML, Brantly ML, Aslanidi G. Multiplexing AAV Serotype-Specific Neutralizing Antibodies in Preclinical Animal Models and Humans. Biomedicines 2023; 11:biomedicines11020523. [PMID: 36831059 PMCID: PMC9953293 DOI: 10.3390/biomedicines11020523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 01/29/2023] [Accepted: 02/07/2023] [Indexed: 02/16/2023] Open
Abstract
The accurate assessment of AAV-specific pre-existing humoral immunity due to natural viral infection is critical for the efficient use of clinical gene therapy. The method described in the present study applies equivalent infection conditions to each AAV serotype (AAV1, AAV2, AAV3, AAV5, AAV6, AAV7, AAV8, AAV9, AAV10, and AAVAnc80L65). In the current study, we validated the assay by assessing AAV-neutralizing antibody titers in a limited cohort of random human donors and well-established preclinical large animal models, including dogs and non-human primates (NHPs). We achieved a rapid and accurate evaluation of neutralizing titers for each individual subject that can be used for clinical enrollment based on specific AAV serotypes and individualized selection of the most suitable AAV serotype for each specific patient.
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Affiliation(s)
- Hisae Kuoch
- The Hormel Institute, University of Minnesota, 801 16th Avenue NE, Austin, MN 55912, USA
| | - Karina Krotova
- The Hormel Institute, University of Minnesota, 801 16th Avenue NE, Austin, MN 55912, USA
| | - Melanie L. Graham
- Department of Surgery, Medical School, University of Minnesota, Minneapolis, MN 55108, USA
| | - Mark L. Brantly
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, Medical School, University of Florida, Gainesville, FL 32610, USA
| | - George Aslanidi
- The Hormel Institute, University of Minnesota, 801 16th Avenue NE, Austin, MN 55912, USA
- Correspondence: ; Tel.: +1-507-437-9622; Fax: +1-507-437-9606
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5
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Simmons E, Wen Y, Li J, Qian YW, Wong LC, Konrad RJ, Bivi N. A sensitive and drug tolerant assay for detecting anti-AAV9 antibodies using affinity capture elution. J Immunol Methods 2023; 512:113397. [PMID: 36481208 DOI: 10.1016/j.jim.2022.113397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 11/09/2022] [Accepted: 11/30/2022] [Indexed: 12/08/2022]
Abstract
Adeno-associated virus (AAV) based gene therapies are gaining significant momentum as a novel therapeutic modality. However, a yet unsolved concern for using AAV as a vector is the high potential to elicit humoral and cellular responses, which are often exacerbated by pre-existing immunity due to exposure to wild type AAV. Therefore, characterization of pre-existing and treatment emergent anti-AAV antibodies is of great importance to the development of AAV based gene therapies. In this project, a sensitive and drug tolerant total antibody (TAb) assay was developed using recombinant AAV9-GFP (green fluorescent protein) as a surrogate AAV9. The assay format was affinity capture and elution (ACE) with ruthenium labeled AAV9-GFP as detection. Upon evaluation, three commercial anti-AAV9 monoclonal antibodies (clones HI17, HI35, and HL2374) were chosen and mixed at equal concentrations as positive control material. The assay sensitivity was estimated to be 11.2 ng/mL. Drug tolerance was estimated to be 5.4 × 10E10 DRP/mL AAV9-GFP at 100 ng/mL anti-AAV9 antibodies and to be at least 1 × 10E11 DRP/mL at 500 ng/mL and 250 ng/mL anti-AAV9 antibodies. The assay showed desirable specificity and precision. Using this TAb assay, significant pre-existing antibodies were detected from normal human sera.
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Affiliation(s)
- Emma Simmons
- Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, IN 46285, USA
| | - Yi Wen
- Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, IN 46285, USA.
| | - Jingling Li
- Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, IN 46285, USA
| | - Yue-Wei Qian
- Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, IN 46285, USA
| | - Li Chin Wong
- Prevail Therapeutics - a Wholly-Owned Subsidiary of Eli Lilly and Company, New York, NY 10016, USA
| | - Robert J Konrad
- Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, IN 46285, USA
| | - Nicoletta Bivi
- Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, IN 46285, USA
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Daniel HDJ, Kumar S, Kannangai R, Farzana J, Joel JN, Abraham A, Lakshmi KM, Agbandje-Mckenna M, Coleman KE, Srivastava A, Srivastava A, Abraham AM. Age-stratified adeno-associated virus serotype 3 neutralizing and total antibody prevalence in hemophilia A patients from India. J Med Virol 2022; 94:4542-4547. [PMID: 35577570 DOI: 10.1002/jmv.27859] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 05/09/2022] [Accepted: 05/11/2022] [Indexed: 11/08/2022]
Abstract
Gene therapy using adeno-associated virus (AAV) vector offers a new treatment option for individuals with monogenetic disorders. The major bottleneck is the presence of pre-existing anti-AAV antibodies, which impacts its use. Even very low titers of neutralizing antibodies (NAb) to capsids from natural AAV infections have been reported to inhibit the transduction of intravenously administered AAV in animal models and are associated with limited efficacy in human trials. Assessing the level of pre-existing NAb is important for determining the primary eligibility of patients for AAV vector-based gene therapy clinical trials. Techniques used to screen AAV-antibodies include AAV capsid ELISA and transduction inhibition assay (TIA) for detecting total capsid-binding (TAb) and Nab, respectively. In this study, we screened 521 individuals with hemophilia A from India for TAb and NAb using ELISA and TIA, respectively. The prevalence of TAb and NAb in hemophilia A patients from India were 96 % and 77.5%, respectively. There was a significant increase in anti-AAV3 NAb prevalence with age in the hemophilia A patient group from India. There was a trend in anti-AAV3 TAb positivity between the pediatric age group (94.4%) and the adult age group (97.4%). This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Hubert D-J Daniel
- Center for Stem Cell Research, Christian Medical College, Vellore, India.,Department of Clinical Virology
| | - Sanjay Kumar
- Center for Stem Cell Research, Christian Medical College, Vellore, India
| | | | - J Farzana
- Center for Stem Cell Research, Christian Medical College, Vellore, India
| | - Joseph N Joel
- Center for Stem Cell Research, Christian Medical College, Vellore, India
| | - Aby Abraham
- Department of Hematology, Christian Medical College, Vellore, India
| | | | | | | | | | - Alok Srivastava
- Center for Stem Cell Research, Christian Medical College, Vellore, India.,Department of Hematology, Christian Medical College, Vellore, India
| | - Asha Mary Abraham
- Center for Stem Cell Research, Christian Medical College, Vellore, India.,Department of Clinical Virology
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Sphingosine-1-phosphate transporter spinster homolog 2 is essential for iron-regulated metastasis of hepatocellular carcinoma. Mol Ther 2022; 30:703-713. [PMID: 34547466 PMCID: PMC8821935 DOI: 10.1016/j.ymthe.2021.09.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 07/04/2021] [Accepted: 09/14/2021] [Indexed: 02/04/2023] Open
Abstract
Iron dyshomeostasis is associated with hepatocellular carcinoma (HCC) development. However, the role of iron in HCC metastasis is unknown. This study aimed to elucidate the underlying mechanisms of iron's enhancement activity on HCC metastasis. In addition to the HCC cell lines and clinical samples in vitro, iron-deficient (ID) mouse models were generated using iron-free diet and transferrin receptor protein knockout, followed by administration of HCC tumors through either orthotopic or ectopic route. Clinical metastatic HCC samples showed significant ID status, accompanied by overexpression of sphingosine-1-phosphate transporter spinster homolog 2 (SPNS2). Mechanistically, ID increased SPNS2 expression, leading to HCC metastasis in both cell cultures and mouse models. ID not only altered the anti-tumor immunity, which was indicated by phenotypes of lymphatic subsets in the liver and lung of tumor-bearing mice, but also promoted HCC metastasis in a cancer cell autonomous manner through the SPNS2. Since germline knockout of globe SPNS2 showed significantly reduced HCC metastasis, we further developed hepatic-targeting recombinant adeno-associated virus vectors to knockdown SPNS2 expression and to inhibit iron-regulated HCC metastasis. Our observation indicates the role of iron in HCC pulmonary metastasis and suggests SPNS2 as a potential therapeutic target for the prevention of HCC pulmonary metastasis.
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Khatri A, Shelke R, Guan S, Somanathan S. Higher seroprevalence of anti-AAV NAb among racial minorities in the United States. Hum Gene Ther 2021; 33:442-450. [PMID: 34861783 PMCID: PMC9063129 DOI: 10.1089/hum.2021.243] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Anti-AAV neutralizing antibodies (NAbs) can ablate efficacy of transgene expression following intravenous vector administration. This observation in both preclinical and clinical trials has led to exclusion of NAb positive patients from receiving AAV gene therapy. AAV drug development includes selection of capsids with lower NAb seroprevalence, that also possess other favorable traits. Often a limited number of healthy volunteers are screened to gauge NAb seroprevalence. However, limited data sets can be biased leading to inaccurate estimates of NAb incidence. Here we evaluated AAV NAbs against a panel of vectors among healthy donors within the United States. While the overall seroprevalence against most AAVs was lower, we did observe increased NAb incidence among Black and Hispanic donors. These findings of increased NAb seroprevalence among the minority races were confirmed in a second set of donors that also demonstrated higher seroprevalence among these races. Interracial-and intraracial differences within genders was also observed among donors. The increased incidence of AAV NAb among racial minorities was unexpected. Our findings underscore the need for removing bias in sample data sets and evaluating seroprevalence within the patient population while selecting capsids.
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Affiliation(s)
- Arpana Khatri
- Pfizer Inc, 2253, Rare disease research unit, Cambridge, Massachusetts, United States;
| | - Rajani Shelke
- Pfizer Inc, 2253, Rare Diseases Research Unit, Cambridge, Massachusetts, United States;
| | - Shunjie Guan
- Pfizer Inc, 2253, Rare Diseases Research Unit, Cambridge, Massachusetts, United States.,Pfizer Inc, 2253, Early Clinical Development, Cambridge, Massachusetts, United States;
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Colón-Thillet R, Jerome KR, Stone D. Optimization of AAV vectors to target persistent viral reservoirs. Virol J 2021; 18:85. [PMID: 33892762 PMCID: PMC8067653 DOI: 10.1186/s12985-021-01555-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Accepted: 04/14/2021] [Indexed: 12/18/2022] Open
Abstract
Gene delivery of antiviral therapeutics to anatomical sites where viruses accumulate and persist is a promising approach for the next generation of antiviral therapies. Recombinant adeno-associated viruses (AAV) are one of the leading vectors for gene therapy applications that deliver gene-editing enzymes, antibodies, and RNA interference molecules to eliminate viral reservoirs that fuel persistent infections. As long-lived viral DNA within specific cellular reservoirs is responsible for persistent hepatitis B virus, Herpes simplex virus, and human immunodeficiency virus infections, the discovery of AAV vectors with strong tropism for hepatocytes, sensory neurons and T cells, respectively, is of particular interest. Identification of natural isolates from various tissues in humans and non-human primates has generated an extensive catalog of AAV vectors with diverse tropisms and transduction efficiencies, which has been further expanded through molecular genetic approaches. The AAV capsid protein, which forms the virions' outer shell, is the primary determinant of tissue tropism, transduction efficiency, and immunogenicity. Thus, over the past few decades, extensive efforts to optimize AAV vectors for gene therapy applications have focused on capsid engineering with approaches such as directed evolution and rational design. These approaches are being used to identify variants with improved transduction efficiencies, alternate tropisms, reduced sequestration in non-target organs, and reduced immunogenicity, and have produced AAV capsids that are currently under evaluation in pre-clinical and clinical trials. This review will summarize the most recent strategies to identify AAV vectors with enhanced tropism and transduction in cell types that harbor viral reservoirs.
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Affiliation(s)
- Rossana Colón-Thillet
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, 1100 Fairview Ave N, Seattle, WA, USA
| | - Keith R Jerome
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, 1100 Fairview Ave N, Seattle, WA, USA
- Department of Laboratory Medicine, University of Washington, Seattle, WA, USA
| | - Daniel Stone
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, 1100 Fairview Ave N, Seattle, WA, USA.
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Daniel HDJ, Kumar S, Kannangai R, Lakshmi KM, Agbandje-Mckenna M, Coleman K, Srivastava A, Srivastava A, Abraham AM. Prevalence of Adeno-Associated Virus 3 Capsid Binding and Neutralizing Antibodies in Healthy and Hemophilia B Individuals from India. Hum Gene Ther 2021; 32:451-457. [PMID: 33207962 DOI: 10.1089/hum.2020.258] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Adeno-associated virus (AAV) vector-based gene therapy offers a new treatment option for individuals with hemophilia. Pre-existing anti-AAV antibodies significantly impact the use of AAV vectors. Even relatively low titers of AAV neutralizing antibodies (NAb) from natural AAV infections against the capsid have been shown to inhibit the transduction of intravenously administered AAV in animal models and were associated with limited efficacy in human trials. This is important for determining the primary eligibility of patients for AAV vector-based gene therapy clinical trials. Current techniques to screen AAV antibodies include AAV capsid enzyme-linked immunosorbent assay (ELISA) for total antibodies and a transduction inhibition assay (TIA) for NAb. This study developed and screened total capsid binding anti-AAV3 antibodies by using ELISA and determined NAb levels by TIA using mCherry flow cytometry in healthy individuals with hemophilia B in India. One hundred and forty-three apparently healthy controls and 92 individuals with hemophilia B were screened. The prevalence of total and NAb in healthy controls was 79.7% and 65%, respectively; the prevalence of total and NAb in patients with hemophilia B for AAV3 was 92.4% and 91.3%, respectively.
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Affiliation(s)
- Hubert D-J Daniel
- Center for Stem Cell Research, Christian Medical College, Vellore, India; Departments of.,Clinical Virology
| | - Sanjay Kumar
- Center for Stem Cell Research, Christian Medical College, Vellore, India; Departments of
| | | | - Kavitha M Lakshmi
- Hematology, Christian Medical College, Vellore, India; Departments of
| | | | - Kirsten Coleman
- Powel Gene Therapy Center Toxicology Core, University of Florida, Gainesville, Florida, USA
| | - Arun Srivastava
- Pediatrics, University of Florida, Gainesville, Florida, USA
| | - Alok Srivastava
- Center for Stem Cell Research, Christian Medical College, Vellore, India; Departments of.,Hematology, Christian Medical College, Vellore, India; Departments of
| | - Asha Mary Abraham
- Center for Stem Cell Research, Christian Medical College, Vellore, India; Departments of.,Clinical Virology
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Ertl HCJ. T Cell-Mediated Immune Responses to AAV and AAV Vectors. Front Immunol 2021; 12:666666. [PMID: 33927727 PMCID: PMC8076552 DOI: 10.3389/fimmu.2021.666666] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Accepted: 03/22/2021] [Indexed: 12/18/2022] Open
Abstract
Adeno-associated virus (AAV)-mediated gene transfer has benefited patients with inherited diseases, such as hemophilia B, by achieving long-term expression of the therapeutic transgene. Nevertheless, challenges remain due to rejection of AAV-transduced cells, which in some, but not all, patients can be prevented by immunosuppression. It is assumed that CD8+ T cells induced by natural infections with AAVs are recalled by the AAV vector's capsid and upon activation eliminate cells expressing the degraded capsid antigens. Alternatively, it is feasible that AAV vectors, especially if given at high doses, induce de novo capsid- or transgene product-specific T cell responses. This chapter discusses CD8+ T cell responses to AAV infections and AAV gene transfer and avenues to prevent their activation or block their effector functions.
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12
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Qin W, Xu G, Tai PWL, Wang C, Luo L, Li C, Hu X, Xue J, Lu Y, Zhou Q, Wei Q, Wen T, Hu J, Xiao Y, Yang L, Li W, Flotte TR, Wei Y, Gao G. Large-scale molecular epidemiological analysis of AAV in a cancer patient population. Oncogene 2021; 40:3060-3071. [PMID: 33782545 PMCID: PMC8087635 DOI: 10.1038/s41388-021-01725-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Revised: 01/28/2021] [Accepted: 02/18/2021] [Indexed: 02/06/2023]
Abstract
Recombinant adeno-associated viruses (rAAVs) are well-established vectors for delivering therapeutic genes. However, previous reports have suggested that wild-type AAV is linked to hepatocellular carcinoma, raising concern with the safety of rAAVs. In addition, a recent long-term follow-up study in canines, which received rAAVs for factor VIII gene therapy, demonstrated vector integration into the genome of liver cells, reviving the uncertainty between AAV and cancer. To further explore this relationship, we performed large-scale molecular epidemiology of AAV in resected tumor samples and non-lesion tissues collected from 413 patients, reflecting nine carcinoma types: breast carcinoma, rectal cancer, pancreas carcinoma, brain tumor, hepatoid adenocarcinoma, hepatocellular carcinoma, gastric carcinoma, lung squamous, and adenocarcinoma. We found that over 80% of patients were AAV-positive among all nine types of carcinoma examined. Importantly, the AAV sequences detected in patient-matched tumor and adjacent non-lesion tissues showed no significant difference in incidence, abundance, and variation. Additionally, no specific AAV sequences predominated in tumor samples. Our data shows that AAV genomes are equally abundant in tumors and adjacent normal tissues, but lack clonality. The finding critically adds to the epidemiological profile of AAV in humans, and provides insights that may assist rAAV-based clinical studies and gene therapy strategies.
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Affiliation(s)
- Wanru Qin
- State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Guangchao Xu
- State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China.,Horae Gene Therapy Center, University of Massachusetts, Medical School, Worcester, MA, USA.,Microbiology and Physiological Systems, University of Massachusetts, Medical School, Worcester, MA, USA
| | - Phillip W L Tai
- Horae Gene Therapy Center, University of Massachusetts, Medical School, Worcester, MA, USA.,Microbiology and Physiological Systems, University of Massachusetts, Medical School, Worcester, MA, USA
| | - Chunmei Wang
- State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Li Luo
- State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China.,Horae Gene Therapy Center, University of Massachusetts, Medical School, Worcester, MA, USA
| | | | - Xun Hu
- Biobank, West China Hospital, Sichuan University, Chengdu, China
| | - Jianxin Xue
- Department of Thoracic Oncology and State Key Laboratory of Biotherapy, Cancer Center, West China Hospital, Sichuan University, Chengdu, China
| | - You Lu
- Department of Thoracic Oncology and State Key Laboratory of Biotherapy, Cancer Center, West China Hospital, Sichuan University, Chengdu, China
| | - Qiao Zhou
- Pathology Department and State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu, China
| | - Qiang Wei
- Department of Urology, Institute of Urology, West China Hospital, Sichuan University, Chengdu, China
| | - Tianfu Wen
- Department of Liver Surgery, West China Hospital, Sichuan University, Chengdu, China
| | - Jiankun Hu
- Department of Gastrointestinal Surgery and Laboratory of Gastric Cancer, West China Hospital, Sichuan University, Chengdu, China
| | - Yuanyuan Xiao
- State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Li Yang
- State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Weimin Li
- State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Terence R Flotte
- Horae Gene Therapy Center, University of Massachusetts, Medical School, Worcester, MA, USA. .,Pediatrics, University of Massachusetts, Medical School, Worcester, MA, USA.
| | - Yuquan Wei
- State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China.
| | - Guangping Gao
- Horae Gene Therapy Center, University of Massachusetts, Medical School, Worcester, MA, USA. .,Microbiology and Physiological Systems, University of Massachusetts, Medical School, Worcester, MA, USA.
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13
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Qian R, Xiao B, Li J, Xiao X. Directed Evolution of AAV Serotype 5 for Increased Hepatocyte Transduction and Retained Low Humoral Seroreactivity. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2020; 20:122-132. [PMID: 33426144 PMCID: PMC7773954 DOI: 10.1016/j.omtm.2020.10.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Accepted: 10/13/2020] [Indexed: 02/08/2023]
Abstract
Most recombinant adeno-associated virus (AAV) capsids utilized in liver gene therapy have significant levels of pre-existing neutralizing antibodies in the human population. These neutralizing factors limit the patient pools eligible for receiving AAV-mediated therapies. AAV serotype 5 (AAV5) does not face the same barrier of humoral immunity as most AAV serotypes due to its low seroprevalence. However, AAV5 can only facilitate a low level of transgene expression in the liver, constraining its application to a small number of liver diseases. To improve the liver transduction of AAV5 while retaining its low seroprevalence, we constructed a library of AAV5 mutants via random mutagenesis and screened in Huh7 cells. Two molecularly evolved AAV5 variants, MV50 and MV53, demonstrated significantly increased transduction efficiency in Huh7 cells (∼12×) and primary human hepatocytes (∼10×). All variants had retained low seroreactivity toward pooled human immunoglobulin G (IgG) when compared to AAV5, which was significantly less seroreactive than AAV9. Functional characterization of the mutants also revealed insights into the functions of various domains, especially the VR-I, in the AAV5 capsid. The result is AAV5 variant capsids with much enhanced human hepatocyte transduction, potentially useful for liver-directed gene therapy.
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Affiliation(s)
- Randolph Qian
- Division of Pharmacoengineering and Molecular Pharmaceutics, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC 27517, USA
| | - Bin Xiao
- Division of Pharmacoengineering and Molecular Pharmaceutics, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC 27517, USA
| | - Juan Li
- Division of Pharmacoengineering and Molecular Pharmaceutics, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC 27517, USA
| | - Xiao Xiao
- Division of Pharmacoengineering and Molecular Pharmaceutics, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC 27517, USA
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14
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Kruzik A, Fetahagic D, Hartlieb B, Dorn S, Koppensteiner H, Horling FM, Scheiflinger F, Reipert BM, de la Rosa M. Prevalence of Anti-Adeno-Associated Virus Immune Responses in International Cohorts of Healthy Donors. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2019; 14:126-133. [PMID: 31338384 PMCID: PMC6629972 DOI: 10.1016/j.omtm.2019.05.014] [Citation(s) in RCA: 82] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 05/20/2019] [Indexed: 11/09/2022]
Abstract
Preexisting immunity against adeno-associated virus (AAV) is a major challenge facing AAV gene therapy, resulting in the exclusion of patients from clinical trials. Accordingly, proper assessment of anti-AAV immunity is necessary for understanding clinical data and for product development. Previous studies on anti-AAV prevalence lack method standardization, rendering the assessment of prevalence difficult. Addressing this need, we used clinical assays that were validated according to guidelines for a comprehensive characterization of anti-AAV1, -AAV2, -AAV5, and -AAV8 immunity in large international cohorts of healthy donors and patients with hemophilia B. Here, we report a higher than expected average prevalence for anti-AAV8 (∼40%) and anti-AAV5 (∼30%) neutralizing antibodies (NAbs), which is supported by strongly correlating anti-AAV IgG antibody titers. A similar anti-AAV8 NAb prevalence was observed in hemophilia B patients. In addition, a high co-prevalence of NAbs against other serotypes makes switching to gene therapy using another serotype difficult. As anti-AAV T cell responses are believed to influence transduction, we characterized anti-AAV T cell responses using interleukin-2 (IL-2) and interferon-γ (IFN-γ) ELISpot assays, revealing a similar prevalence of IFN-γ responses (∼20%) against different serotypes that did not correlate with NAbs. These data, along with the long-term stability of NAbs, emphasize the need to develop strategies to circumvent anti-AAV immunity.
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Affiliation(s)
- Anita Kruzik
- Baxalta Innovations GmbH, a member of the Takeda group of companies, Vienna, Austria
| | - Damir Fetahagic
- Baxalta Innovations GmbH, a member of the Takeda group of companies, Vienna, Austria
| | - Bettina Hartlieb
- Baxalta Innovations GmbH, a member of the Takeda group of companies, Vienna, Austria
| | - Sebastian Dorn
- Baxalta Innovations GmbH, a member of the Takeda group of companies, Vienna, Austria
| | - Herwig Koppensteiner
- Baxalta Innovations GmbH, a member of the Takeda group of companies, Vienna, Austria
| | - Frank M Horling
- Baxalta Innovations GmbH, a member of the Takeda group of companies, Vienna, Austria
| | | | - Birgit M Reipert
- Baxalta Innovations GmbH, a member of the Takeda group of companies, Vienna, Austria
| | - Maurus de la Rosa
- Baxalta Innovations GmbH, a member of the Takeda group of companies, Vienna, Austria
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15
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Kruzik A, Koppensteiner H, Fetahagic D, Hartlieb B, Dorn S, Romeder-Finger S, Coulibaly S, Weber A, Hoellriegl W, Horling FM, Scheiflinger F, Reipert BM, de la Rosa M. Detection of Biologically Relevant Low-Titer Neutralizing Antibodies Against Adeno-Associated Virus Require Sensitive In Vitro Assays. Hum Gene Ther Methods 2019; 30:35-43. [DOI: 10.1089/hgtb.2018.263] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Affiliation(s)
- Anita Kruzik
- Baxalta Innovations GmbH, a member of the Takeda group of companies, Vienna, Austria
| | - Herwig Koppensteiner
- Baxalta Innovations GmbH, a member of the Takeda group of companies, Vienna, Austria
| | - Damir Fetahagic
- Baxalta Innovations GmbH, a member of the Takeda group of companies, Vienna, Austria
| | - Bettina Hartlieb
- Baxalta Innovations GmbH, a member of the Takeda group of companies, Vienna, Austria
| | - Sebastian Dorn
- Baxalta Innovations GmbH, a member of the Takeda group of companies, Vienna, Austria
| | - Stefan Romeder-Finger
- Baxalta Innovations GmbH, a member of the Takeda group of companies, Vienna, Austria
| | - Sogue Coulibaly
- Baxalta Innovations GmbH, a member of the Takeda group of companies, Vienna, Austria
| | - Alfred Weber
- Baxalta Innovations GmbH, a member of the Takeda group of companies, Vienna, Austria
| | - Werner Hoellriegl
- Baxalta Innovations GmbH, a member of the Takeda group of companies, Vienna, Austria
| | - Frank M. Horling
- Baxalta Innovations GmbH, a member of the Takeda group of companies, Vienna, Austria
| | | | - Birgit M. Reipert
- Baxalta Innovations GmbH, a member of the Takeda group of companies, Vienna, Austria
| | - Maurus de la Rosa
- Baxalta Innovations GmbH, a member of the Takeda group of companies, Vienna, Austria
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16
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Perocheau DP, Cunningham SC, Lee J, Antinao Diaz J, Waddington SN, Gilmour K, Eaglestone S, Lisowski L, Thrasher AJ, Alexander IE, Gissen P, Baruteau J. Age-Related Seroprevalence of Antibodies Against AAV-LK03 in a UK Population Cohort. Hum Gene Ther 2019; 30:79-87. [PMID: 30027761 PMCID: PMC6343184 DOI: 10.1089/hum.2018.098] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 06/28/2018] [Indexed: 12/16/2022] Open
Abstract
Recombinant adeno-associated virus (rAAV) vectors are a promising platform for in vivo gene therapy. The presence of neutralizing antibodies (Nab) against AAV capsids decreases cell transduction efficiency and is a common exclusion criterion for participation in clinical trials. Novel engineered capsids are being generated to improve gene delivery to the target cells and facilitate success of clinical trials; however, the prevalence of antibodies against such capsids remains largely unknown. We therefore assessed the seroprevalence of antibodies against a novel synthetic liver-tropic capsid AAV-LK03. We measured seroprevalence of immunoglobulin (Ig)G (i.e., neutralizing and nonneutralizing) antibodies and Nab to AAV-LK03 in a cohort of 323 UK patients (including 260 pediatric) and 52 juvenile rhesus macaques. We also performed comparative analysis of seroprevalence of Nab against wild-type AAV8 and AAV3B capsids. Overall IgG seroprevalence for AAV-LK03 was 39% in human samples. The titer increased with age. Prevalence of Nab was 23%, 35%, and 18% for AAV-LK03, AAV3B, and AAV8, respectively, with the lowest seroprevalence between 3 and 17 years of age for all serotypes. Presence of Nab against AAV-LK03 decreased from 36% in the youngest cohort (birth to 6 months) to 7% in older primary school-age children (9-11 years) and then progressively increased to 54% in late adulthood. Cross-reactivity between serotypes was >60%. Nab seroprevalence in macaques was 62%, 85%, and 40% for AAV-LK03, AAV3B, and AAV8, respectively. When planning for AAV gene therapy clinical trials, knowing the seropositivity of the target population is critical. In the population studied, AAV seroprevalence for AAV serotypes tested was low. However, high cross-reactivity between AAV serotypes remains a barrier for re-injection. Shifts in Nab seroprevalence during the first decade need to be confirmed by longitudinal studies. This possibility suggests that pediatric patients could respond differently to AAV therapy according to age. If late childhood is an ideal age window, intervention at an early age when maternal Nab levels are high may be challenging. Nab-positive children excluded from trials could be rescreened for eligibility at regular intervals because this status may change.
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Affiliation(s)
- Dany P. Perocheau
- Genetics and Genomic Medicine Programme, Great Ormond Street Institute of Child Health, University College London, London, United Kingdom
- Gene Transfer Technology Group, Institute for Women's Health, University College London, London, United Kingdom
| | - Sharon C. Cunningham
- Gene Therapy Research Unit, Children's Medical Research Institute, Faculty of Medicine and Health, University of Sydney and Sydney Children's Hospital Network, Westmead, Australia
| | - Juhee Lee
- Genetics and Genomic Medicine Programme, Great Ormond Street Institute of Child Health, University College London, London, United Kingdom
- Gene Transfer Technology Group, Institute for Women's Health, University College London, London, United Kingdom
| | - Juan Antinao Diaz
- Gene Transfer Technology Group, Institute for Women's Health, University College London, London, United Kingdom
| | - Simon N. Waddington
- Gene Transfer Technology Group, Institute for Women's Health, University College London, London, United Kingdom
- Antiviral Gene Therapy Research Unit, Faculty of Health Sciences, University of the Witswatersrand, Johannesburg, South Africa
| | - Kimberly Gilmour
- Clinical Immunology Department, Great Ormond Street Hospital for Children NHS Foundation Trust, London, United Kingdom
| | - Simon Eaglestone
- Translational Research Office, University College London, London, United Kingdom
| | - Leszek Lisowski
- Gene Therapy Research Unit, Children's Medical Research Institute, Faculty of Medicine and Health, University of Sydney and Sydney Children's Hospital Network, Westmead, Australia
- Translational Vectorology Group, Children's Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, Australia
- Military Institute of Hygiene and Epidemiology, The Biological Threats Identification and Countermeasure Centre, Puławy, Poland
| | - Adrian J. Thrasher
- Clinical Immunology Department, Great Ormond Street Hospital for Children NHS Foundation Trust, London, United Kingdom
- Infection, Immunity and Inflammation Programme, Great Ormond Street Institute of Child Health, University College London, London, United Kingdom
| | - Ian E. Alexander
- Gene Therapy Research Unit, Children's Medical Research Institute, Faculty of Medicine and Health, University of Sydney and Sydney Children's Hospital Network, Westmead, Australia
- Discipline of Child and Adolescent Health, Sydney Medical School, Faculty of Medicine and Health, University of Sydney, Westmead, Australia
| | - Paul Gissen
- Genetics and Genomic Medicine Programme, Great Ormond Street Institute of Child Health, University College London, London, United Kingdom
- MRC Laboratory for Molecular Biology, University College London, London, United Kingdom
- Metabolic Medicine Department, Great Ormond Street Hospital for Children NHS Foundation Trust, London, United Kingdom
| | - Julien Baruteau
- Genetics and Genomic Medicine Programme, Great Ormond Street Institute of Child Health, University College London, London, United Kingdom
- Gene Transfer Technology Group, Institute for Women's Health, University College London, London, United Kingdom
- Metabolic Medicine Department, Great Ormond Street Hospital for Children NHS Foundation Trust, London, United Kingdom
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17
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Paulk NK, Pekrun K, Zhu E, Nygaard S, Li B, Xu J, Chu K, Leborgne C, Dane AP, Haft A, Zhang Y, Zhang F, Morton C, Valentine MB, Davidoff AM, Nathwani AC, Mingozzi F, Grompe M, Alexander IE, Lisowski L, Kay MA. Bioengineered AAV Capsids with Combined High Human Liver Transduction In Vivo and Unique Humoral Seroreactivity. Mol Ther 2018; 26:289-303. [PMID: 29055620 PMCID: PMC5763027 DOI: 10.1016/j.ymthe.2017.09.021] [Citation(s) in RCA: 117] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Revised: 09/17/2017] [Accepted: 09/20/2017] [Indexed: 01/01/2023] Open
Abstract
Existing recombinant adeno-associated virus (rAAV) serotypes for delivering in vivo gene therapy treatments for human liver diseases have not yielded combined high-level human hepatocyte transduction and favorable humoral neutralization properties in diverse patient groups. Yet, these combined properties are important for therapeutic efficacy. To bioengineer capsids that exhibit both unique seroreactivity profiles and functionally transduce human hepatocytes at therapeutically relevant levels, we performed multiplexed sequential directed evolution screens using diverse capsid libraries in both primary human hepatocytes in vivo and with pooled human sera from thousands of patients. AAV libraries were subjected to five rounds of in vivo selection in xenografted mice with human livers to isolate an enriched human-hepatotropic library that was then used as input for a sequential on-bead screen against pooled human immunoglobulins. Evolved variants were vectorized and validated against existing hepatotropic serotypes. Two of the evolved AAV serotypes, NP40 and NP59, exhibited dramatically improved functional human hepatocyte transduction in vivo in xenografted mice with human livers, along with favorable human seroreactivity profiles, compared with existing serotypes. These novel capsids represent enhanced vector delivery systems for future human liver gene therapy applications.
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Affiliation(s)
- Nicole K Paulk
- Departments of Pediatrics and Genetics, Stanford University, Stanford, CA 94305, USA
| | - Katja Pekrun
- Departments of Pediatrics and Genetics, Stanford University, Stanford, CA 94305, USA
| | - Erhua Zhu
- Translational Vectorology Group, Children's Medical Research Institute, University of Sydney, Sydney, NSW, Australia
| | - Sean Nygaard
- Oregon Stem Cell Center, Oregon Health & Science University, Portland, OR 97239, USA
| | - Bin Li
- Oregon Stem Cell Center, Oregon Health & Science University, Portland, OR 97239, USA
| | - Jianpeng Xu
- Departments of Pediatrics and Genetics, Stanford University, Stanford, CA 94305, USA
| | - Kirk Chu
- Departments of Pediatrics and Genetics, Stanford University, Stanford, CA 94305, USA
| | | | - Allison P Dane
- Department of Haematology, UCL Cancer Institute, London, UK
| | - Annelise Haft
- Oregon Stem Cell Center, Oregon Health & Science University, Portland, OR 97239, USA
| | - Yue Zhang
- Departments of Pediatrics and Genetics, Stanford University, Stanford, CA 94305, USA
| | - Feijie Zhang
- Departments of Pediatrics and Genetics, Stanford University, Stanford, CA 94305, USA
| | - Chris Morton
- Department of Surgery, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Marcus B Valentine
- Cytogenetic Shared Resource, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Andrew M Davidoff
- Department of Surgery, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Amit C Nathwani
- Department of Haematology, UCL Cancer Institute, London, UK; Department of Haematology and Katharine Dormandy Haemophilia Centre & Thrombosis Unit, Royal Free London NHS Foundation Trust Hospital, London, UK; National Health Services Blood and Transplant, Watford, UK
| | - Federico Mingozzi
- Genethon and INSERM U951, Evry, France; University Pierre and Marie Curie, Paris, France
| | - Markus Grompe
- Oregon Stem Cell Center, Oregon Health & Science University, Portland, OR 97239, USA
| | - Ian E Alexander
- Translational Vectorology Group, Children's Medical Research Institute, University of Sydney, Sydney, NSW, Australia
| | - Leszek Lisowski
- Translational Vectorology Group, Children's Medical Research Institute, University of Sydney, Sydney, NSW, Australia; Military Institute of Hygiene and Epidemiology (MIHE), Puławy, Poland
| | - Mark A Kay
- Departments of Pediatrics and Genetics, Stanford University, Stanford, CA 94305, USA.
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18
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Calcedo R, Wilson JM. AAV Natural Infection Induces Broad Cross-Neutralizing Antibody Responses to Multiple AAV Serotypes in Chimpanzees. HUM GENE THER CL DEV 2017; 27:79-82. [PMID: 27314914 DOI: 10.1089/humc.2016.048] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Cross-sectional studies of primates have revealed that natural neutralizing antibody (NAb) responses to adeno-associated viruses (AAV) span multiple serotypes. This differs from the phenotype of the NAb response to an AAV vector delivered to seronegative nonhuman primates that is typically restricted to the administered AAV serotype. To better understand the mechanism by which natural AAV infections result in broad NAb responses, we conducted a longitudinal study spanning 10 years in which we evaluated serum-circulating AAV NAb levels in captive-housed chimpanzees. In a cohort of 25 chimpanzees we identified 3 distinct groups of animals: those that never seroconverted to AAV (naïve), those that were persistently seropositive (chronic), and those that seroconverted during the 10-year period (acute). For the chronic group we found a broad seroresponse characterized by NAbs reacting to multiple AAV serotypes. A similar cross-neutralization pattern of NAbs was observed in the acute group. These data support our hypothesis that a single natural infection with AAV induces a broadly cross-reactive NAb response to multiple AAV serotypes.
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Affiliation(s)
- Roberto Calcedo
- Gene Therapy Program, Department of Medicine, University of Pennsylvania , Philadelphia, Pennsylvania
| | - James M Wilson
- Gene Therapy Program, Department of Medicine, University of Pennsylvania , Philadelphia, Pennsylvania
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19
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Yao T, Zhou X, Zhang C, Yu X, Tian Z, Zhang L, Zhou D. Site-Specific PEGylated Adeno-Associated Viruses with Increased Serum Stability and Reduced Immunogenicity. Molecules 2017; 22:molecules22071155. [PMID: 28696391 PMCID: PMC6152081 DOI: 10.3390/molecules22071155] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Revised: 07/05/2017] [Accepted: 07/07/2017] [Indexed: 02/02/2023] Open
Abstract
Adeno-associated virus (AAV) is one of the most extensively studied and utilized viral vectors in clinical gene transfer research. However, the serum instability and immunogenicity of AAV vectors significantly limit their application. Here, we endeavored to overcome these limitations by developing a straightforward approach for site-specific PEGylation of AAV via genetic code expansion. This technique includes incorporation of the azide moiety into the AAV capsid protein followed by orthogonal and stoichiometric conjugation of a variety of polyethylene glycols (PEGs) through click chemistry. Using this approach, only the chosen site(s) was consistently PEGylated under mild conditions, preventing nonselective conjugation. Upon a series of in vitro examinations, AAVs conjugated with 20-kD PEG at sites Q325+1, S452+1, and R585+1 showed a 1.7- to 2.4-fold stability improvement in pooled human serum and a nearly twofold reduction in antibody recognition. Subsequent animal research on Sprague Dawley rats displayed a promising 20% reduction in antibody inducement and a higher virus titer in the blood. Together, our data demonstrate successful protection of an AAV vector from antibody neutralization and blood clearance, thereby increasing the efficiency of therapeutic gene delivery.
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Affiliation(s)
- Tianzhuo Yao
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, 100191 Beijing, China.
| | - Xueying Zhou
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, 100191 Beijing, China.
| | - Chuanling Zhang
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, 100191 Beijing, China.
| | - Xiaojuan Yu
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, 100191 Beijing, China.
| | - Zhenyu Tian
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, 100191 Beijing, China.
| | - Lihe Zhang
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, 100191 Beijing, China.
| | - Demin Zhou
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, 100191 Beijing, China.
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20
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Ling C, Li B, Ma W, Srivastava A. Development of Optimized AAV Serotype Vectors for High-Efficiency Transduction at Further Reduced Doses. Hum Gene Ther Methods 2017; 27:143-9. [PMID: 27431826 DOI: 10.1089/hgtb.2016.054] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
We have described the development of capsid-modified next-generation AAV vectors for both AAV2 and AAV3 serotypes, in which specific surface-exposed tyrosine (Y), serine (S), threonine (T), and lysine (K) residues on viral capsids were modified to achieve high-efficiency transduction at lower doses. We have also described the development of genome-modified AAV vectors, in which the transcriptionally inactive, single-stranded AAV genome was modified to achieve improved transgene expression. Here, we describe that combination of capsid modifications and genome modifications leads to the generation of optimized AAV serotype vectors, which transduce cells and tissues more efficiently, both in vitro and in vivo, at ∼20-30-fold reduced doses. These studies have significant implications in the potential use of the optimized AAV serotype vectors in human gene therapy.
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Affiliation(s)
- Chen Ling
- 1 Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida College of Medicine , Gainesville, Florida.,2 Powell Gene Therapy Center, University of Florida College of Medicine , Gainesville, Florida.,3 Shands Cancer Center, University of Florida College of Medicine , Gainesville, Florida
| | - Baozheng Li
- 1 Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida College of Medicine , Gainesville, Florida
| | - Wenqin Ma
- 1 Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida College of Medicine , Gainesville, Florida
| | - Arun Srivastava
- 1 Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida College of Medicine , Gainesville, Florida.,2 Powell Gene Therapy Center, University of Florida College of Medicine , Gainesville, Florida.,3 Shands Cancer Center, University of Florida College of Medicine , Gainesville, Florida.,4 Genetics Institute, University of Florida College of Medicine , Gainesville, Florida.,5 Department of Molecular Genetics and Microbiology, University of Florida College of Medicine , Gainesville, Florida
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21
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Wang Z, Zhai Z, Du X. Celastrol inhibits migration and invasion through blocking the NF-κB pathway in ovarian cancer cells. Exp Ther Med 2017; 14:819-824. [PMID: 28673005 DOI: 10.3892/etm.2017.4568] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Accepted: 03/10/2017] [Indexed: 12/16/2022] Open
Abstract
Metastatic ovarian cancer is a major clinical challenge with poor prognosis and high mortality. Celastrol is a natural compound that has exhibits antiproliferative activity; however, its effects on metastasis-related phenotypes in ovarian cancer models are unclear. In the current study, the anti-invasive activities and associated signaling pathways of celastrol were determined in ovarian cancer cells. Cell proliferation was tested by MTT assay. Cell migration was detected by wound healing and Transwell assays, while cell invasion was detected by a Matrigel-coated Transwell method. In addition, nuclear factor (NF)-κB and matrix metalloproteinase (MMP) expression was examined by western blotting, and MMP-2/-9 activities were determined by gelatin zymography. At sub-toxic concentrations (<0.5 µM), celastrol inhibited migration and invasion in a concentration-dependent manner in SKOV-3 and OVCAR-3 cells. At the molecular level, celastrol blocked the canonical NF-κB pathway by inhibiting IκBα phosphorylation, and preventing IκBα degradation and p65 accumulation. Furthermore, the expression and activity of the NF-κB target protein MMP-9, but not MMP-2, were inhibited by celastrol. Furthermore, celastrol showed no synergistic effect with MG132, an NF-κB inhibitor. In conclusion, celastrol exhibited significant anti-invasive activities in ovarian cancer cells. Such functions may be mediated via NF-κB pathway blockade. The results of this in vitro study strengthen the value of applying celastrol as a potential clinical intervention modality for delaying ovarian cancer metastasis. This, celastrol warrants further preclinical investigation.
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Affiliation(s)
- Zhongye Wang
- Department of Obstetrics and Gynecology, Weihai Central Hospital, Weihai, Shandong 264400, P.R. China
| | - Zhenyuan Zhai
- Department of Obstetrics and Gynecology, Weihai Central Hospital, Weihai, Shandong 264400, P.R. China
| | - Xiulan Du
- Department of Obstetrics and Gynecology, Weihai Central Hospital, Weihai, Shandong 264400, P.R. China
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22
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Ling C, Yin Z, Li J, Zhang D, Aslanidi G, Srivastava A. Strategies to generate high-titer, high-potency recombinant AAV3 serotype vectors. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2016; 3:16029. [PMID: 27200382 PMCID: PMC4856060 DOI: 10.1038/mtm.2016.29] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Revised: 03/17/2016] [Accepted: 03/18/2016] [Indexed: 02/08/2023]
Abstract
Although recombinant adeno-associated virus serotype 3 (AAV3) vectors were largely ignored previously, owing to their poor transduction efficiency in most cells and tissues examined, our initial observation of the selective tropism of AAV3 serotype vectors for human liver cancer cell lines and primary human hepatocytes has led to renewed interest in this serotype. AAV3 vectors and their variants have recently proven to be extremely efficient in targeting human and nonhuman primate hepatocytes in vitro as well as in vivo. In the present studies, we wished to evaluate the relative contributions of the cis-acting inverted terminal repeats (ITRs) from AAV3 (ITR3), as well as the trans-acting Rep proteins from AAV3 (Rep3) in the AAV3 vector production and transduction. To this end, we utilized two helper plasmids: pAAVr2c3, which carries rep2 and cap3 genes, and pAAVr3c3, which carries rep3 and cap3 genes. The combined use of AAV3 ITRs, AAV3 Rep proteins, and AAV3 capsids led to the production of recombinant vectors, AAV3-Rep3/ITR3, with up to approximately two to fourfold higher titers than AAV3-Rep2/ITR2 vectors produced using AAV2 ITRs, AAV2 Rep proteins, and AAV3 capsids. We also observed that the transduction efficiency of Rep3/ITR3 AAV3 vectors was approximately fourfold higher than that of Rep2/ITR2 AAV3 vectors in human hepatocellular carcinoma cell lines in vitro. The transduction efficiency of Rep3/ITR3 vectors was increased by ~10-fold, when AAV3 capsids containing mutations in two surface-exposed residues (serine 663 and threonine 492) were used to generate a S663V+T492V double-mutant AAV3 vector. The Rep3/ITR3 AAV3 vectors also transduced human liver tumors in vivo approximately twofold more efficiently than those generated with Rep2/ITR2. Our data suggest that the transduction efficiency of AAV3 vectors can be significantly improved both using homologous Rep proteins and ITRs as well as by capsid optimization. Thus, the combined use of homologous Rep proteins, ITRs, and capsids should also lead to more efficacious other AAV serotype vectors for their optimal use in human gene therapy.
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Affiliation(s)
- Chen Ling
- Division of Cellular and Molecular Therapy, Department of Pediatrics; University of Florida College of Medicine, Gainesville, Florida, USA; Powell Gene Therapy Center; University of Florida College of Medicine, Gainesville, Florida, USA; Shands Cancer Center; University of Florida College of Medicine, Gainesville, Florida, USA
| | - Zifei Yin
- Division of Cellular and Molecular Therapy, Department of Pediatrics; University of Florida College of Medicine , Gainesville, Florida, USA
| | - Jun Li
- Division of Cellular and Molecular Therapy, Department of Pediatrics; University of Florida College of Medicine , Gainesville, Florida, USA
| | - Daniel Zhang
- Division of Cellular and Molecular Therapy, Department of Pediatrics; University of Florida College of Medicine , Gainesville, Florida, USA
| | - George Aslanidi
- Division of Cellular and Molecular Therapy, Department of Pediatrics; University of Florida College of Medicine, Gainesville, Florida, USA; Powell Gene Therapy Center; University of Florida College of Medicine, Gainesville, Florida, USA
| | - Arun Srivastava
- Division of Cellular and Molecular Therapy, Department of Pediatrics; University of Florida College of Medicine, Gainesville, Florida, USA; Powell Gene Therapy Center; University of Florida College of Medicine, Gainesville, Florida, USA; Shands Cancer Center; University of Florida College of Medicine, Gainesville, Florida, USA; Genetics Institute; University of Florida College of Medicine, Gainesville, Florida, USA; Department of Molecular Genetics & Microbiology; University of Florida College of Medicine, Gainesville, Florida, USA
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23
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Li S, Ling C, Zhong L, Li M, Su Q, He R, Tang Q, Greiner DL, Shultz LD, Brehm MA, Flotte TR, Mueller C, Srivastava A, Gao G. Efficient and Targeted Transduction of Nonhuman Primate Liver With Systemically Delivered Optimized AAV3B Vectors. Mol Ther 2015; 23:1867-76. [PMID: 26403887 PMCID: PMC4700112 DOI: 10.1038/mt.2015.174] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2015] [Accepted: 09/14/2015] [Indexed: 12/19/2022] Open
Abstract
Recombinant adeno-associated virus serotype 3B (rAAV3B) can transduce cultured human liver cancer cells and primary human hepatocytes efficiently. Serine (S)- and threonine (T)-directed capsid modifications further augment its transduction efficiency. Systemically delivered capsid-optimized rAAV3B vectors can specifically target cancer cells in a human liver cancer xenograft model, suggesting their potential use for human liver-directed gene therapy. Here, we compared transduction efficiencies of AAV3B and AAV8 vectors in cultured primary human hepatocytes and cancer cells as well as in human and mouse hepatocytes in a human liver xenograft NSG-PiZ mouse model. We also examined the safety and transduction efficacy of wild-type (WT) and capsid-optimized rAAV3B in the livers of nonhuman primates (NHPs). Intravenously delivered S663V+T492V (ST)-modified self-complementary (sc) AAV3B-EGFP vectors led to liver-targeted robust enhanced green fluorescence protein (EGFP) expression in NHPs without apparent hepatotoxicity. Intravenous injections of both WT and ST-modified rAAV3B.ST-rhCG vectors also generated stable super-physiological levels of rhesus chorionic gonadotropin (rhCG) in NHPs. The vector genome predominantly targeted the liver. Clinical chemistry and histopathology examinations showed no apparent vector-related toxicity. Our studies should be important and informative for clinical development of optimized AAV3B vectors for human liver-directed gene therapy.
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Affiliation(s)
- Shaoyong Li
- Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, Massachusetts, USA
- Department of Microbiology and Physiology Systems, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Chen Ling
- Powell Gene Therapy Center, University of Florida, Gainesville, Florida, USA
- Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida, Gainesville, Florida, USA
| | - Li Zhong
- Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, Massachusetts, USA
- Viral Vector Core, University of Massachusetts Medical School, Worcester, Massachusetts, USA
- Department of Pediatrics, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Mengxin Li
- Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, Massachusetts, USA
- Department of Microbiology and Physiology Systems, University of Massachusetts Medical School, Worcester, Massachusetts, USA
- Department of Pediatrics, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Qin Su
- Viral Vector Core, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Ran He
- Viral Vector Core, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Qiushi Tang
- Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, Massachusetts, USA
- Department of Pediatrics, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Dale L Greiner
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | | | - Michael A Brehm
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Terence R Flotte
- Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, Massachusetts, USA
- Department of Pediatrics, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Christian Mueller
- Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, Massachusetts, USA
- Department of Pediatrics, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Arun Srivastava
- Powell Gene Therapy Center, University of Florida, Gainesville, Florida, USA
- Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida, Gainesville, Florida, USA
| | - Guangping Gao
- Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, Massachusetts, USA
- Department of Microbiology and Physiology Systems, University of Massachusetts Medical School, Worcester, Massachusetts, USA
- Viral Vector Core, University of Massachusetts Medical School, Worcester, Massachusetts, USA
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