1
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Kumar SRP, Biswas M, Cao D, Arisa S, Muñoz-Melero M, Lam AK, Piñeros AR, Kapur R, Kaisho T, Kaufman RJ, Xiao W, Shayakhmetov DM, Terhorst C, de Jong YP, Herzog RW. TLR9-independent CD8 + T cell responses in hepatic AAV gene transfer through IL-1R1-MyD88 signaling. Mol Ther 2024; 32:325-339. [PMID: 38053332 PMCID: PMC10861967 DOI: 10.1016/j.ymthe.2023.11.029] [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: 10/27/2023] [Revised: 11/14/2023] [Accepted: 11/30/2023] [Indexed: 12/07/2023] Open
Abstract
Upon viral infection of the liver, CD8+ T cell responses may be triggered despite the immune suppressive properties that manifest in this organ. We sought to identify pathways that activate responses to a neoantigen expressed in hepatocytes, using adeno-associated viral (AAV) gene transfer. It was previously established that cooperation between plasmacytoid dendritic cells (pDCs), which sense AAV genomes by Toll-like receptor 9 (TLR9), and conventional DCs promotes cross-priming of capsid-specific CD8+ T cells. Surprisingly, we find local initiation of a CD8+ T cell response against antigen expressed in ∼20% of murine hepatocytes, independent of TLR9 or type I interferons and instead relying on IL-1 receptor 1-MyD88 signaling. Both IL-1α and IL-1β contribute to this response, which can be blunted by IL-1 blockade. Upon AAV administration, IL-1-producing pDCs infiltrate the liver and co-cluster with XCR1+ DCs, CD8+ T cells, and Kupffer cells. Analogous events were observed following coagulation factor VIII gene transfer in hemophilia A mice. Therefore, pDCs have alternative means of promoting anti-viral T cell responses and participate in intrahepatic immune cell networks similar to those that form in lymphoid organs. Combined TLR9 and IL-1 blockade may broadly prevent CD8+ T responses against AAV capsid and transgene product.
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Affiliation(s)
- Sandeep R P Kumar
- Department of Pediatrics, Herman B Wells Center for Pediatric Research, Indiana University, Indianapolis, IN, USA
| | - Moanaro Biswas
- Department of Pediatrics, Herman B Wells Center for Pediatric Research, Indiana University, Indianapolis, IN, USA
| | - Di Cao
- Department of Pediatrics, Herman B Wells Center for Pediatric Research, Indiana University, Indianapolis, IN, USA
| | - Sreevani Arisa
- Department of Pediatrics, Herman B Wells Center for Pediatric Research, Indiana University, Indianapolis, IN, USA
| | - Maite Muñoz-Melero
- Department of Pediatrics, Herman B Wells Center for Pediatric Research, Indiana University, Indianapolis, IN, USA
| | - Anh K Lam
- Department of Pediatrics, Herman B Wells Center for Pediatric Research, Indiana University, Indianapolis, IN, USA
| | - Annie R Piñeros
- Department of Pediatrics, Herman B Wells Center for Pediatric Research, Indiana University, Indianapolis, IN, USA
| | - Reuben Kapur
- Department of Pediatrics, Herman B Wells Center for Pediatric Research, Indiana University, Indianapolis, IN, USA
| | - Tsuneyasu Kaisho
- Department of Immunology, Institute of Advanced Medicine, Wakayama Medical University, Wakayama, Japan
| | - Randal J Kaufman
- Center for Genetic Disorders and Aging Research, Samford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Weidong Xiao
- Department of Pediatrics, Herman B Wells Center for Pediatric Research, Indiana University, Indianapolis, IN, USA
| | - Dmitry M Shayakhmetov
- Lowance Center for Human Immunology, Emory Vaccine Center, Departments of Pediatrics and Medicine, Emory University School of Medicine, Atlanta, GA, USA
| | - Cox Terhorst
- Division of Immunology, Beth Israel Deaconess Medical Center (BIDMC), Boston, MA, USA
| | - Ype P de Jong
- Division of Gastroenterology & Hepatology, Weill Cornell Medicine, New York, NY, USA
| | - Roland W Herzog
- Department of Pediatrics, Herman B Wells Center for Pediatric Research, Indiana University, Indianapolis, IN, USA.
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2
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Yang P, Mustafi D, Pepple KL. Immunology of Retinitis Pigmentosa and Gene Therapy-Associated Uveitis. Cold Spring Harb Perspect Med 2024; 14:a041305. [PMID: 37037600 PMCID: PMC10562523 DOI: 10.1101/cshperspect.a041305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
Abstract
The underlying immune state of inherited retinal degenerations (IRDs) and retinitis pigmentosa (RP) has been an emerging area of interest, wherein the consequences have never been greater given the widespread recognition of gene therapy-associated uveitis (GTU) in gene therapy clinical trials. Whereas some evidence suggests that the adaptive immune system may play a role, the majority of studies indicate that the innate immune system is likely the primary driver of neuroinflammation in RP. During retinal degeneration, discrete mechanisms activate resident microglia and promote infiltrating macrophages that can either be protective or detrimental to photoreceptor cell death. This persistent stimulation of innate immunity, overlaid by the introduction of viral antigens as part of gene therapy, has the potential to trigger a complex microglia/macrophage-driven proinflammatory state. A better understanding of the immune pathophysiology in IRD and GTU will be necessary to improve the success of developing novel treatments for IRDs.
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Affiliation(s)
- Paul Yang
- Casey Eye Institute, Oregon Health & Science University, Portland, Oregan 97239, USA
| | - Debarshi Mustafi
- Department of Ophthalmology, Roger and Karalis Johnson Retina Center, University of Washington, Seattle, Washington 98109, USA
- Brotman Baty Institute for Precision Medicine, Seattle, Washington 98109, USA
- Department of Ophthalmology, Seattle Children's Hospital, Seattle, Washington 98109, USA
| | - Kathryn L Pepple
- Department of Ophthalmology, Roger and Karalis Johnson Retina Center, University of Washington, Seattle, Washington 98109, USA
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3
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Rghei AD, Cao W, He S, Lopes JA, Zielinska N, Pei Y, Thompson B, Banadyga L, Wootton SK. AAV-Vectored Expression of Marburg Virus-Neutralizing Antibody MR191 Provides Complete Protection From Challenge in a Guinea Pig Model. J Infect Dis 2023; 228:S682-S690. [PMID: 37638865 PMCID: PMC10651196 DOI: 10.1093/infdis/jiad345] [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: 03/30/2023] [Revised: 08/11/2023] [Accepted: 08/11/2023] [Indexed: 08/29/2023] Open
Abstract
Although there are no approved countermeasures available to prevent or treat disease caused by Marburg virus (MARV), potently neutralizing monoclonal antibodies (mAbs) derived from B cells of human survivors have been identified. One such mAb, MR191, has been shown to provide complete protection against MARV in nonhuman primates. We previously demonstrated that prophylactic administration of an adeno-associated virus (AAV) expressing MR191 protected mice from MARV. Here, we modified the AAV-MR191 coding sequence to enhance efficacy and reevaluated protection in a guinea pig model. Remarkably, 4 different variants of AAV-MR191 provided complete protection against MARV, despite administration 90 days prior to challenge. Based on superior expression kinetics, AAV-MR191-io2, was selected for evaluation in a dose-reduction experiment. The highest dose provided 100% protection, while a lower dose provided ∼88% protection. These data confirm the efficacy of AAV-mediated expression of MR191 and support the further development of this promising MARV countermeasure.
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Affiliation(s)
- Amira D Rghei
- Department of Pathobiology, University of Guelph, Guelph, Ontario, Canada
| | - Wenguang Cao
- Special Pathogens Program, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada
| | - Shihua He
- Special Pathogens Program, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada
| | - Jordyn A Lopes
- Department of Pathobiology, University of Guelph, Guelph, Ontario, Canada
| | - Nicole Zielinska
- Department of Pathobiology, University of Guelph, Guelph, Ontario, Canada
| | - Yanlong Pei
- Department of Pathobiology, University of Guelph, Guelph, Ontario, Canada
| | | | - Logan Banadyga
- Special Pathogens Program, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada
- Department of Medical Microbiology and Infectious Diseases, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Sarah K Wootton
- Department of Pathobiology, University of Guelph, Guelph, Ontario, Canada
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4
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Bentler M, Hardet R, Ertelt M, Rudolf D, Kaniowska D, Schneider A, Vondran FW, Schoeder CT, Delphin M, Lucifora J, Ott M, Hacker UT, Adriouch S, Büning H. Modifying immune responses to adeno-associated virus vectors by capsid engineering. Mol Ther Methods Clin Dev 2023; 30:576-592. [PMID: 37693943 PMCID: PMC10485635 DOI: 10.1016/j.omtm.2023.08.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Accepted: 08/18/2023] [Indexed: 09/12/2023]
Abstract
De novo immune responses are considered major challenges in gene therapy. With the aim to lower innate immune responses directly in cells targeted by adeno-associated virus (AAV) vectors, we equipped the vector capsid with a peptide known to interfere with Toll-like receptor signaling. Specifically, we genetically inserted in each of the 60 AAV2 capsid subunits the myeloid differentiation primary response 88 (MyD88)-derived peptide RDVLPGT, known to block MyD88 dimerization. Inserting the peptide neither interfered with capsid assembly nor with vector production yield. The novel capsid variant, AAV2.MB453, showed superior transduction efficiency compared to AAV2 in human monocyte-derived dendritic cells and in primary human hepatocyte cultures. In line with our hypothesis, AAV2.MB453 and AAV2 differed regarding innate immune response activation in primary human cells, particularly for type I interferons. Furthermore, mice treated with AAV2.MB453 showed significantly reduced CD8+ T cell responses against the transgene product for different administration routes and against the capsid following intramuscular administration. Moreover, humoral responses against the capsid were mitigated as indicated by delayed IgG2a antibody formation and an increased NAb50. To conclude, insertion of the MyD88-derived peptide into the AAV2 capsid improved early steps of host-vector interaction and reduced innate and adaptive immune responses.
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Affiliation(s)
- Martin Bentler
- Institute of Experimental Hematology, Hannover Medical School, 30625 Hannover, Germany
| | - Romain Hardet
- University of Rouen, INSERM, U1234, Pathophysiology Autoimmunity and Immunotherapy (PANTHER), Normandie University, 76000 Rouen, France
| | - Moritz Ertelt
- Institute for Drug Discovery, University of Leipzig Medical Center, 04103 Leipzig, Germany
- Center for Scalable Data Analytics and Artificial Intelligence (ScaDS.AI), Dresden/Leipzig, Germany
| | - Daniela Rudolf
- Laboratory for Vector Based Immunotherapy, Fraunhofer Institute for Cell Therapy and Immunology (IZI), 04103 Leipzig, Germany
| | - Dorota Kaniowska
- Laboratory for Vector Based Immunotherapy, Fraunhofer Institute for Cell Therapy and Immunology (IZI), 04103 Leipzig, Germany
- Department of Medicine II, University Cancer Center Leipzig (UCCL), University of Leipzig Medical Center, 04103 Leipzig, Germany
| | - Andreas Schneider
- Institute of Experimental Hematology, Hannover Medical School, 30625 Hannover, Germany
| | - Florian W.R. Vondran
- ReMediES, Department of General, Visceral and Transplant Surgery, Hannover Medical School, 30625 Hannover, Germany
- German Center for Infection Research (DZIF), Partner Site Hannover-Braunschweig, 38124 Braunschweig, Germany
| | - Clara T. Schoeder
- Institute for Drug Discovery, University of Leipzig Medical Center, 04103 Leipzig, Germany
| | - Marion Delphin
- CIRI, Centre International de Recherche en Infectiologie, Université de Lyon, Inserm U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, ENS de Lyon, 69007 Lyon, France
| | - Julie Lucifora
- CIRI, Centre International de Recherche en Infectiologie, Université de Lyon, Inserm U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, ENS de Lyon, 69007 Lyon, France
| | - Michael Ott
- Department of Gastroenterology, Hepatology, and Endocrinology, Hannover Medical School, 30625 Hannover, Germany
| | - Ulrich T. Hacker
- Institute of Experimental Hematology, Hannover Medical School, 30625 Hannover, Germany
- Laboratory for Vector Based Immunotherapy, Fraunhofer Institute for Cell Therapy and Immunology (IZI), 04103 Leipzig, Germany
- Department of Medicine II, University Cancer Center Leipzig (UCCL), University of Leipzig Medical Center, 04103 Leipzig, Germany
| | - Sahil Adriouch
- University of Rouen, INSERM, U1234, Pathophysiology Autoimmunity and Immunotherapy (PANTHER), Normandie University, 76000 Rouen, France
| | - Hildegard Büning
- Institute of Experimental Hematology, Hannover Medical School, 30625 Hannover, Germany
- German Center for Infection Research (DZIF), Partner Site Hannover-Braunschweig, 38124 Braunschweig, Germany
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5
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Costa-Verdera H, Unzu C, Valeri E, Adriouch S, González Aseguinolaza G, Mingozzi F, Kajaste-Rudnitski A. Understanding and Tackling Immune Responses to Adeno-Associated Viral Vectors. Hum Gene Ther 2023; 34:836-852. [PMID: 37672519 DOI: 10.1089/hum.2023.119] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/08/2023] Open
Abstract
As the clinical experience in adeno-associated viral (AAV) vector-based gene therapies is expanding, the necessity to better understand and control the host immune responses is also increasing. Immunogenicity of AAV vectors in humans has been linked to several limitations of the platform, including lack of efficacy due to antibody-mediated neutralization, tissue inflammation, loss of transgene expression, and in some cases, complement activation and acute toxicities. Nevertheless, significant knowledge gaps remain in our understanding of the mechanisms of immune responses to AAV gene therapies, further hampered by the failure of preclinical animal models to recapitulate clinical findings. In this review, we focus on the current knowledge regarding immune responses, spanning from innate immunity to humoral and adaptive responses, triggered by AAV vectors and how they can be mitigated for safer, durable, and more effective gene therapies.
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Affiliation(s)
- Helena Costa-Verdera
- San Raffaele Telethon Institute for Gene Therapy (SR-TIGET), IRCSS Ospedale San Raffaele, Milan, Italy
| | - Carmen Unzu
- DNA and RNA Medicine Division, CIMA, Universidad de Navarra, IdisNA, Pamplona, Spain
| | - Erika Valeri
- San Raffaele Telethon Institute for Gene Therapy (SR-TIGET), IRCSS Ospedale San Raffaele, Milan, Italy
| | - Sahil Adriouch
- University of Rouen, INSERM, U1234, Pathophysiology Autoimmunity and Immunotherapy (PANTHER), Normandie University, Rouen, France
| | - Gloria González Aseguinolaza
- DNA and RNA Medicine Division, CIMA, Universidad de Navarra, IdisNA, Pamplona, Spain
- Vivet Therapeutics S.L., Pamplona, Spain; and
| | | | - Anna Kajaste-Rudnitski
- San Raffaele Telethon Institute for Gene Therapy (SR-TIGET), IRCSS Ospedale San Raffaele, Milan, Italy
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6
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Kaczmarek R, Piñeros AR, Patterson PE, Bertolini TB, Perrin GQ, Sherman A, Born J, Arisa S, Arvin MC, Kamocka MM, Martinez MM, Dunn KW, Quinn SM, Morris JJ, Wilhelm AR, Kaisho T, Munoz-Melero M, Biswas M, Kaplan MH, Linnemann AK, George LA, Camire RM, Herzog RW. Factor VIII trafficking to CD4+ T cells shapes its immunogenicity and requires several types of antigen-presenting cells. Blood 2023; 142:290-305. [PMID: 37192286 PMCID: PMC10375270 DOI: 10.1182/blood.2022018937] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 04/20/2023] [Accepted: 04/27/2023] [Indexed: 05/18/2023] Open
Abstract
Despite >80 years of clinical experience with coagulation factor VIII (FVIII) inhibitors, surprisingly little is known about the in vivo mechanism of this most serious complication of replacement therapy for hemophilia A. These neutralizing antidrug alloantibodies arise in ∼30% of patients. Inhibitor formation is T-cell dependent, but events leading up to helper T-cell activation have been elusive because of, in part, the complex anatomy and cellular makeup of the spleen. Here, we show that FVIII antigen presentation to CD4+ T cells critically depends on a select set of several anatomically distinct antigen-presenting cells, whereby marginal zone B cells and marginal zone and marginal metallophilic macrophages but not red pulp macrophages (RPMFs) participate in shuttling FVIII to the white pulp in which conventional dendritic cells (DCs) prime helper T cells, which then differentiate into follicular helper T (Tfh) cells. Toll-like receptor 9 stimulation accelerated Tfh cell responses and germinal center and inhibitor formation, whereas systemic administration of FVIII alone in hemophilia A mice increased frequencies of monocyte-derived and plasmacytoid DCs. Moreover, FVIII enhanced T-cell proliferation to another protein antigen (ovalbumin), and inflammatory signaling-deficient mice were less likely to develop inhibitors, indicating that FVIII may have intrinsic immunostimulatory properties. Ovalbumin, which, unlike FVIII, is absorbed into the RPMF compartment, fails to elicit T-cell proliferative and antibody responses when administered at the same dose as FVIII. Altogether, we propose that an antigen trafficking pattern that results in efficient in vivo delivery to DCs and inflammatory signaling, shape the immunogenicity of FVIII.
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Affiliation(s)
- Radoslaw Kaczmarek
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN
| | - Annie R. Piñeros
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN
| | - Paige E. Patterson
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN
| | - Thais B. Bertolini
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN
| | - George Q. Perrin
- Department of Pediatrics, University of Florida, Gainesville, FL
| | | | - Jameson Born
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN
| | - Sreevani Arisa
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN
| | - Matthew C. Arvin
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN
| | - Malgorzata M. Kamocka
- Division of Nephrology, Department of Medicine, Indiana University School of Medicine, Indianapolis, IN
| | - Michelle M. Martinez
- Division of Nephrology, Department of Medicine, Indiana University School of Medicine, Indianapolis, IN
| | - Kenneth W. Dunn
- Division of Nephrology, Department of Medicine, Indiana University School of Medicine, Indianapolis, IN
| | - Sean M. Quinn
- Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA
- Division of Hematology and Raymond G. Perelman Center for Cellular and Molecular Therapeutics, Children's Hospital of Philadelphia, Philadelphia, PA
| | - Johnathan J. Morris
- Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA
- Division of Hematology and Raymond G. Perelman Center for Cellular and Molecular Therapeutics, Children's Hospital of Philadelphia, Philadelphia, PA
| | - Amelia R. Wilhelm
- Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA
- Division of Hematology and Raymond G. Perelman Center for Cellular and Molecular Therapeutics, Children's Hospital of Philadelphia, Philadelphia, PA
| | - Tsuneyasu Kaisho
- Department of Immunology, Institute of Advanced Medicine, Wakayama Medical University, Wakayama, Japan
- Laboratory for Inflammatory Regulation, RIKEN Center for Integrative Medical Sciences, Yokohama, Japan
| | - Maite Munoz-Melero
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN
| | - Moanaro Biswas
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN
| | - Mark H. Kaplan
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, IN
| | - Amelia K. Linnemann
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN
- Indiana Center for Diabetes and Metabolic Diseases, Indiana University School of Medicine, Indianapolis, IN
| | - Lindsey A. George
- Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA
- Division of Hematology and Raymond G. Perelman Center for Cellular and Molecular Therapeutics, Children's Hospital of Philadelphia, Philadelphia, PA
| | - Rodney M. Camire
- Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA
- Division of Hematology and Raymond G. Perelman Center for Cellular and Molecular Therapeutics, Children's Hospital of Philadelphia, Philadelphia, PA
| | - Roland W. Herzog
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN
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7
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Rogers GL, Huang C, Mathur A, Huang X, Chen HY, Stanten K, Morales H, Chang CH, Kezirian EJ, Cannon PM. Reprogramming human B cells with custom heavy chain antibodies. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.28.546944. [PMID: 37425794 PMCID: PMC10327003 DOI: 10.1101/2023.06.28.546944] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/11/2023]
Abstract
We describe a genome editing strategy to reprogram the immunoglobulin heavy chain (IgH) locus of human B cells to express custom molecules that respond to immunization. These heavy chain antibodies (HCAbs) comprise a custom antigen-recognition domain linked to an Fc domain derived from the IgH locus and can be differentially spliced to express either B cell receptor (BCR) or secreted antibody isoforms. The HCAb editing platform is highly flexible, supporting antigen-binding domains based on both antibody and non-antibody components, and also allowing alterations in the Fc domain. Using HIV Env protein as a model antigen, we show that B cells edited to express anti-Env HCAbs support the regulated expression of both BCRs and antibodies, and respond to Env antigen in a tonsil organoid model of immunization. In this way, human B cells can be reprogrammed to produce customized therapeutic molecules with the potential for in vivo amplification.
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Affiliation(s)
- Geoffrey L. Rogers
- Department of Molecular Microbiology and Immunology, Keck School of Medicine of the University of Southern California, Los Angeles, California, USA
| | - Chun Huang
- Department of Molecular Microbiology and Immunology, Keck School of Medicine of the University of Southern California, Los Angeles, California, USA
| | - Atishay Mathur
- Department of Molecular Microbiology and Immunology, Keck School of Medicine of the University of Southern California, Los Angeles, California, USA
| | - Xiaoli Huang
- Department of Molecular Microbiology and Immunology, Keck School of Medicine of the University of Southern California, Los Angeles, California, USA
| | - Hsu-Yu Chen
- Department of Molecular Microbiology and Immunology, Keck School of Medicine of the University of Southern California, Los Angeles, California, USA
| | - Kalya Stanten
- Department of Molecular Microbiology and Immunology, Keck School of Medicine of the University of Southern California, Los Angeles, California, USA
| | - Heidy Morales
- Department of Molecular Microbiology and Immunology, Keck School of Medicine of the University of Southern California, Los Angeles, California, USA
| | - Chan-Hua Chang
- Department of Molecular Microbiology and Immunology, Keck School of Medicine of the University of Southern California, Los Angeles, California, USA
| | - Eric J. Kezirian
- Department of Otolaryngology, Keck School of Medicine of the University of Southern California, Los Angeles, California, USA
| | - Paula M. Cannon
- Department of Molecular Microbiology and Immunology, Keck School of Medicine of the University of Southern California, Los Angeles, California, USA
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8
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Kumar SR, Duan D, Herzog RW. Immune Responses to Muscle-Directed Adeno-Associated Viral Gene Transfer in Clinical Studies. Hum Gene Ther 2023; 34:365-371. [PMID: 37154743 PMCID: PMC10210217 DOI: 10.1089/hum.2023.056] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Accepted: 05/05/2023] [Indexed: 05/10/2023] Open
Abstract
Muscle-directed gene therapy with adeno-associated viral (AAV) vectors is undergoing clinical development for treating neuromuscular disorders and for systemic delivery of therapeutic proteins. Although these approaches show considerable therapeutic benefits, they are also prone to induce potent immune responses against vector or transgene products owing to the immunogenic nature of the intramuscular delivery route, or the high doses required for systemic delivery to muscle. Major immunological concerns include antibody formation against viral capsid, complement activation, and cytotoxic T cell responses against capsid or transgene products. They can negate therapy and even lead to life-threatening immunotoxicities. Herein we review clinical observations and provide an outlook for how the field addresses these problems through a combination of vector engineering and immune modulation.
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Affiliation(s)
- Sandeep R.P. Kumar
- Department of Pediatrics, Herman B Wells Center for Pediatric Research, Indiana University, Indianapolis, Indiana, USA
| | - Dongsheng Duan
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, Missouri, USA
| | - Roland W. Herzog
- Department of Pediatrics, Herman B Wells Center for Pediatric Research, Indiana University, Indianapolis, Indiana, USA
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9
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Arjomandnejad M, Dasgupta I, Flotte TR, Keeler AM. Immunogenicity of Recombinant Adeno-Associated Virus (AAV) Vectors for Gene Transfer. BioDrugs 2023; 37:311-329. [PMID: 36862289 PMCID: PMC9979149 DOI: 10.1007/s40259-023-00585-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/07/2023] [Indexed: 03/03/2023]
Abstract
Recombinant adeno-associated viruses (AAVs) have emerged as promising gene delivery vehicles resulting in three US Food and Drug Administration (FDA) and one European Medicines Agency (EMA)-approved AAV-based gene therapies. Despite being a leading platform for therapeutic gene transfer in several clinical trials, host immune responses against the AAV vector and transgene have hampered their widespread application. Multiple factors, including vector design, dose, and route of administration, contribute to the overall immunogenicity of AAVs. The immune responses against the AAV capsid and transgene involve an initial innate sensing. The innate immune response subsequently triggers an adaptive immune response to elicit a robust and specific response against the AAV vector. AAV gene therapy clinical trials and preclinical studies provide important information about the immune-mediated toxicities associated with AAV, yet studies suggest preclinical models fail to precisely predict the outcome of gene delivery in humans. This review discusses the contribution of the innate and adaptive immune response against AAVs, highlighting the challenges and potential strategies to mitigate these responses, thereby enhancing the therapeutic potential of AAV gene therapy.
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Affiliation(s)
- Motahareh Arjomandnejad
- Horae Gene Therapy Center, University of Massachusetts Chan Medical School, 386 Plantation Street, Worcester, MA, 01605, USA
| | - Ishani Dasgupta
- Horae Gene Therapy Center, University of Massachusetts Chan Medical School, 386 Plantation Street, Worcester, MA, 01605, USA
| | - Terence R Flotte
- Horae Gene Therapy Center, University of Massachusetts Chan Medical School, 386 Plantation Street, Worcester, MA, 01605, USA
- Department of Pediatrics, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Allison M Keeler
- Horae Gene Therapy Center, University of Massachusetts Chan Medical School, 386 Plantation Street, Worcester, MA, 01605, USA.
- Department of Pediatrics, University of Massachusetts Chan Medical School, Worcester, MA, USA.
- NeuroNexus Institute, University of Massachusetts Chan Medical School, Worcester, MA, USA.
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10
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Ishibashi Y, Sung CYW, Grati M, Chien W. Immune responses in the mammalian inner ear and their implications for AAV-mediated inner ear gene therapy. Hear Res 2023; 432:108735. [PMID: 36965335 DOI: 10.1016/j.heares.2023.108735] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2022] [Revised: 02/17/2023] [Accepted: 03/04/2023] [Indexed: 03/13/2023]
Abstract
Adeno-associated virus (AAV)-mediated inner ear gene therapy is a promising treatment option for hearing loss and dizziness. Several studies have shown that AAV-mediated inner ear gene therapy can be applied to various mouse models of hereditary hearing loss to improve their auditory function. Despite the increase in AAV-based animal and clinical studies aiming to rescue auditory and vestibular functions, little is currently known about the host immune responses to AAV in the mammalian inner ear. It has been reported that the host immune response plays an important role in the safety and efficacy of viral-mediated gene therapy. Therefore, in order for AAV-mediated gene therapy to be successfully and safely translated into patients with hearing loss and dizziness, a better understanding of the host immune responses to AAV in the inner ear is critical. In this review, we summarize the current knowledge on host immune responses to AAV-mediated gene therapy in the mammalian inner ear and other organ systems. We also outline the areas of research that are critical for ensuring the safety and efficacy of AAV-mediated inner ear gene therapy in future clinical and translational studies.
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Affiliation(s)
- Yasuko Ishibashi
- Inner Ear Gene Therapy Program, National Institute on Deafness and Other Communication Disorders (NIDCD), National Institutes of Health, 35A 1F220, 35A Covent Dr., Bethesda, MD 20892, USA; Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders (NIDCD), National Institutes of Health, Bethesda, MD, USA
| | - Cathy Yea Won Sung
- Laboratory of Hearing Biology and Therapeutics, National Institute on Deafness and Other Communication Disorders (NIDCD), National Institutes of Health, Bethesda, MD, USA
| | - Mhamed Grati
- Inner Ear Gene Therapy Program, National Institute on Deafness and Other Communication Disorders (NIDCD), National Institutes of Health, 35A 1F220, 35A Covent Dr., Bethesda, MD 20892, USA
| | - Wade Chien
- Inner Ear Gene Therapy Program, National Institute on Deafness and Other Communication Disorders (NIDCD), National Institutes of Health, 35A 1F220, 35A Covent Dr., Bethesda, MD 20892, USA; Department of Otolaryngology-Head & Neck Surgery, Johns Hopkins School of Medicine, Baltimore, MD, USA.
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11
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Ertl HCJ. Mitigating Serious Adverse Events in Gene Therapy with AAV Vectors: Vector Dose and Immunosuppression. Drugs 2023; 83:287-298. [PMID: 36715794 DOI: 10.1007/s40265-023-01836-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/12/2023] [Indexed: 01/31/2023]
Abstract
Gene transfer with high doses of adeno-associated viral (AAV) vectors has resulted in serious adverse events and even death of the recipients. Toxicity could most likely be circumvented by repeated injections of lower and less toxic doses of vectors. This has not been pursued as AAV vectors induce potent neutralizing antibodies, which prevent cell transduction upon reinjection of the same vector. This review discusses different types of immune responses against AAV vectors and how they offer targets for the elimination or inhibition of vector-specific neutralizing antibodies. Such antibodies can be circumvented by using different virus serotypes for sequential injections, they can be removed by plasmapheresis, or they can be destroyed by enzymatic degradation. Antibody producing cells can be eliminated by proteasome inhibitors. Drugs that inhibit T-cell responses, B-cell signaling, or presentation of the vector's antigens to B cells can prevent or reduce induction of AAV-specific antibodies. Combinations of different approaches and drugs are likely needed to suppress or eliminate neutralizing antibodies, which would then allow for repeated dosing. Alternatively, novel AAV vectors with higher transduction efficacy are being developed and may allow for a dose reduction, although it remains unknown if this will completely address the problem of high-dose adverse events.
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12
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Abstract
Gene therapy is poised to revolutionize modern medicine, with seemingly unlimited potential for treating and curing genetic disorders. For otherwise incurable indications, including most inherited metabolic liver disorders, gene therapy provides a realistic therapeutic option. In this Review, we discuss gene supplementation and gene editing involving the use of recombinant adeno-associated virus (rAAV) vectors for the treatment of inherited liver diseases, including updates on several ongoing clinical trials that are producing promising results. Clinical testing has been essential in highlighting many key translational challenges associated with this transformative therapy. In particular, the interaction of a patient's immune system with the vector raises issues of safety and the duration of treatment efficacy. Furthermore, several serious adverse events after the administration of high doses of rAAVs suggest greater involvement of innate immune responses and pre-existing hepatic conditions than initially anticipated. Finally, permanent modification of the host genome associated with rAAV genome integration and gene editing raises concerns about the risk of oncogenicity that require careful evaluation. We summarize the main progress, challenges and pathways forward for gene therapy for liver diseases.
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13
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Handyside B, Ismail AM, Zhang L, Yates B, Xie L, Sihn CR, Murphy R, Bouwman T, Kim CK, De Angelis R, Karim OA, McIntosh NL, Doss MX, Shroff S, Pungor E, Bhat VS, Bullens S, Bunting S, Fong S. Vector genome loss and epigenetic modifications mediate decline in transgene expression of AAV5 vectors produced in mammalian and insect cells. Mol Ther 2022; 30:3570-3586. [PMID: 36348622 PMCID: PMC9734079 DOI: 10.1016/j.ymthe.2022.11.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 11/03/2022] [Accepted: 11/03/2022] [Indexed: 11/09/2022] Open
Abstract
Recombinant adeno-associated virus (rAAV) vectors are often produced in HEK293 or Spodoptera frugiperda (Sf)-based cell lines. We compared expression profiles of "oversized" (∼5,000 bp) and "standard-sized" (4,600 bp) rAAV5-human α1-antitrypsin (rAAV5-hA1AT) vectors manufactured in HEK293 or Sf cells and investigated molecular mechanisms mediating expression decline. C57BL/6 mice received 6 × 1013 vg/kg of vector, and blood and liver samples were collected through week 57. For all vectors, peak expression (weeks 12-24) declined by 50% to week 57. For Sf- and HEK293-produced oversized vectors, serum hA1AT was initially comparable, but in weeks 12-57, Sf vectors provided significantly higher expression. For HEK293 oversized vectors, liver genomes decreased continuously through week 57 and significantly correlated with A1AT protein. In RNA-sequencing analysis, HEK293 vector-treated mice had significantly higher inflammatory responses in liver at 12 weeks compared with Sf vector- and vehicle-treated mice. Thus, HEK293 vector genome loss led to decreased transgene protein. For Sf-produced vectors, genomes did not decrease from peak expression. Instead, vector genome accessibility significantly decreased from peak to week 57 and correlated with transgene RNA. Vector DNA interactions with active histone marks (H3K27ac/H3K4me3) were significantly reduced from peak to week 57, suggesting that epigenetic regulation impacts transgene expression of Sf-produced vectors.
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Affiliation(s)
- Britta Handyside
- BioMarin Pharmaceutical Inc., 105 Digital Drive, Novato, CA 94949, USA
| | | | - Lening Zhang
- BioMarin Pharmaceutical Inc., 105 Digital Drive, Novato, CA 94949, USA
| | - Bridget Yates
- BioMarin Pharmaceutical Inc., 105 Digital Drive, Novato, CA 94949, USA
| | - Lin Xie
- BioMarin Pharmaceutical Inc., 105 Digital Drive, Novato, CA 94949, USA
| | - Choong-Ryoul Sihn
- BioMarin Pharmaceutical Inc., 105 Digital Drive, Novato, CA 94949, USA
| | - Ryan Murphy
- BioMarin Pharmaceutical Inc., 105 Digital Drive, Novato, CA 94949, USA
| | - Taren Bouwman
- BioMarin Pharmaceutical Inc., 105 Digital Drive, Novato, CA 94949, USA
| | - Chan Kyu Kim
- BioMarin Pharmaceutical Inc., 105 Digital Drive, Novato, CA 94949, USA
| | | | - Omair A. Karim
- BioMarin Pharmaceutical Inc., 105 Digital Drive, Novato, CA 94949, USA
| | | | | | - Shilpa Shroff
- BioMarin Pharmaceutical Inc., 105 Digital Drive, Novato, CA 94949, USA
| | - Erno Pungor
- BioMarin Pharmaceutical Inc., 105 Digital Drive, Novato, CA 94949, USA
| | - Vikas S. Bhat
- BioMarin Pharmaceutical Inc., 105 Digital Drive, Novato, CA 94949, USA
| | - Sherry Bullens
- BioMarin Pharmaceutical Inc., 105 Digital Drive, Novato, CA 94949, USA
| | - Stuart Bunting
- BioMarin Pharmaceutical Inc., 105 Digital Drive, Novato, CA 94949, USA
| | - Sylvia Fong
- BioMarin Pharmaceutical Inc., 105 Digital Drive, Novato, CA 94949, USA,Corresponding author: Sylvia Fong, BioMarin Pharmaceutical Inc., 105 Digital Drive, Novato, CA 94949, USA.
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14
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Prasad S, Dimmock DP, Greenberg B, Walia JS, Sadhu C, Tavakkoli F, Lipshutz GS. Immune Responses and Immunosuppressive Strategies for Adeno-Associated Virus-Based Gene Therapy for Treatment of Central Nervous System Disorders: Current Knowledge and Approaches. Hum Gene Ther 2022; 33:1228-1245. [PMID: 35994385 PMCID: PMC9808800 DOI: 10.1089/hum.2022.138] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Adeno-associated viruses (AAVs) are being increasingly used as gene therapy vectors in clinical studies especially targeting central nervous system (CNS) disorders. Correspondingly, host immune responses to the AAV capsid or the transgene-encoded protein have been observed in various clinical and preclinical studies. Such immune responses may adversely impact patients' health, prevent viral transduction, prevent repeated dosing strategies, eliminate transduced cells, and pose a significant barrier to the potential effectiveness of AAV gene therapy. Consequently, multiple immunomodulatory strategies have been used in attempts to limit immune-mediated responses to the vector, enable readministration of AAV gene therapy, prevent end-organ toxicity, and increase the duration of transgene-encoded protein expression. Herein we review the innate and adaptive immune responses that may occur during CNS-targeted AAV gene therapy as well as host- and treatment-specific factors that could impact the immune response. We also summarize the available preclinical and clinical data on immune responses specifically to CNS-targeted AAV gene therapy and discuss potential strategies for incorporating prophylactic immunosuppression regimens to circumvent adverse immune responses.
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Affiliation(s)
| | - David P. Dimmock
- Rady Children's Institute for Genomic Medicine, Rady Children's Hospital, San Diego, California, USA
| | - Benjamin Greenberg
- Department of Neurology, O'Donnell Brain Institute, University of Texas Southwestern, Dallas, Texas, USA
| | - Jagdeep S. Walia
- Division of Medical Genetics, Department of Pediatrics, Queen's University, Kingston, Canada
| | | | | | - Gerald S. Lipshutz
- Departments of Molecular and Medical Pharmacology and Surgery, Intellectual and Developmental Disabilities Research Center at UCLA, David Geffen School of Medicine at UCLA, Los Angeles, California, USA.,Correspondence: Prof. Gerald S. Lipshutz, Departments of Molecular and Medical Pharmacology and Surgery, Intellectual and Developmental Disabilities Research Center at UCLA, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA.
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15
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Immune profiling of adeno-associated virus response identifies B cell-specific targets that enable vector re-administration in mice. Gene Ther 2022; 30:429-442. [PMID: 36372846 PMCID: PMC10183056 DOI: 10.1038/s41434-022-00371-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Revised: 09/11/2022] [Accepted: 10/04/2022] [Indexed: 11/15/2022]
Abstract
Adeno-associated virus (AAV) vector-based gene therapies can be applied to a wide range of diseases. AAV expression can last for months to years, but vector re-administration may be necessary to achieve life-long treatment. Unfortunately, immune responses against these vectors are potentiated after the first administration, preventing the clinical use of repeated administration of AAVs. Reducing the immune response against AAVs while minimizing broad immunosuppression would improve gene delivery efficiency and long-term safety. In this study, we quantified the contributions of multiple immune system components of the anti-AAV response in mice. We identified B-cell-mediated immunity as a critical component preventing vector re-administration. Additionally, we found that IgG depletion alone was insufficient to enable re-administration, suggesting IgM antibodies play an important role in the immune response against AAV. Further, we found that AAV-mediated transduction is improved in µMT mice that lack functional IgM heavy chains and cannot form mature B-cells relative to wild-type mice. Combined, our results suggest that B-cells, including non-class switched B-cells, are a potential target for therapeutics enabling AAV re-administration. Our results also suggest that the µMT mice are a potentially useful experimental model for gene delivery studies since they allow repeated dosing for more efficient gene delivery from AAVs.
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16
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Shen W, Liu S, Ou L. rAAV immunogenicity, toxicity, and durability in 255 clinical trials: A meta-analysis. Front Immunol 2022; 13:1001263. [PMID: 36389770 PMCID: PMC9647052 DOI: 10.3389/fimmu.2022.1001263] [Citation(s) in RCA: 41] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2022] [Accepted: 10/18/2022] [Indexed: 11/23/2022] Open
Abstract
Recombinant Adeno-associated virus (rAAV) is one of the main delivery vectors for gene therapy. To assess immunogenicity, toxicity, and features of AAV gene therapy in clinical settings, a meta-analysis of 255 clinical trials was performed. A total of 7,289 patients are planned to be dosed. AAV2 was the most dominantly used serotype (29.8%, n=72), and 8.3% (n=20) of trials used engineered capsids. 38.7% (n=91) of trials employed neutralizing antibody assays for patient enrollment, while 15.3% (n=36) used ELISA-based total antibody assays. However, there was high variability in the eligibility criteria with cut-off tiers ranging from 1:1 to 1:1,600. To address potential immunogenicity, 46.3% (n=118) of trials applied immunosuppressants (prophylactic or reactive), while 32.7% (n=18) of CNS and 37.5% (n=24) of ocular-directed trials employed immunosuppressants, possibly due to the immune-privileged status of CNS and retina. There were a total of 11 patient deaths across 8 trials, and 18 out of 30 clinical holds were due to toxicity findings in clinical studies. 30.6% (n=78) of trials had treatment-emergent serious adverse events (TESAEs), with hepatotoxicity and thrombotic microangiopathy (systemic delivery) and neurotoxicity (CNS delivery) being the most prominent. Additionally, the durability of gene therapy may be impacted by two distinct decline mechanisms: 1) rapid decline presumably due to immune responses; or 2) gradual decline due to vector dilution. The durability varied significantly depending on disease indication, dose, serotypes, and patient individuals. Most CNS (90.0%) and muscle trials (73.3%) achieved durable transgene expression, while only 43.6% of ocular trials had sustained clinical outcomes. The rAAV production system can affect rAAV quality and thus immunogenicity and toxicity. Out of 186 trials that have disclosed production system information, 63.0% (n=126) of trials used the transient transfection of the HEK293/HEK293T system, while 18.0% (n=36) applied the baculovirus/Sf9 (rBac/Sf9) system. There were no significant differences in TESAEs and durability between AAV generated by rBac/Sf9 and HEK293/HEK293T systems. In summary, rAAV immunogenicity and toxicity poses significant challenges for clinical development of rAAV gene therapies, and it warrants collaborative efforts to standardize monitoring/measurement methods, design novel strategies to overcome immune responses, and openly share relevant information.
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Affiliation(s)
| | | | - Li Ou
- 3Genemagic Biosciences, Wallingford, PA, United States,4Department of Pediatrics, University of Minnesota, Minneapolis, MN, United States,*Correspondence: Li Ou,
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17
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Yang TY, Braun M, Lembke W, McBlane F, Kamerud J, DeWall S, Tarcsa E, Fang X, Hofer L, Kavita U, Upreti VV, Gupta S, Loo L, Johnson AJ, Chandode RK, Stubenrauch KG, Vinzing M, Xia CQ, Jawa V. Immunogenicity assessment of AAV-based gene therapies: An IQ consortium industry white paper. Mol Ther Methods Clin Dev 2022; 26:471-494. [PMID: 36092368 PMCID: PMC9418752 DOI: 10.1016/j.omtm.2022.07.018] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Immunogenicity has imposed a challenge to efficacy and safety evaluation of adeno-associated virus (AAV) vector-based gene therapies. Mild to severe adverse events observed in clinical development have been implicated with host immune responses against AAV gene therapies, resulting in comprehensive evaluation of immunogenicity during nonclinical and clinical studies mandated by health authorities. Immunogenicity of AAV gene therapies is complex due to the number of risk factors associated with product components and pre-existing immunity in human subjects. Different clinical mitigation strategies have been employed to alleviate treatment-induced or -boosted immunogenicity in order to achieve desired efficacy, reduce toxicity, or treat more patients who are seropositive to AAV vectors. In this review, the immunogenicity risk assessment, manifestation of immunogenicity and its impact in nonclinical and clinical studies, and various clinical mitigation strategies are summarized. Last, we present bioanalytical strategies, methodologies, and assay validation applied to appropriately monitor immunogenicity in AAV gene therapy-treated subjects.
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18
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Gross DA, Tedesco N, Leborgne C, Ronzitti G. Overcoming the Challenges Imposed by Humoral Immunity to AAV Vectors to Achieve Safe and Efficient Gene Transfer in Seropositive Patients. Front Immunol 2022; 13:857276. [PMID: 35464422 PMCID: PMC9022790 DOI: 10.3389/fimmu.2022.857276] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Accepted: 03/16/2022] [Indexed: 11/23/2022] Open
Abstract
One of the major goals of in vivo gene transfer is to achieve long-term expression of therapeutic transgenes in terminally differentiated cells. The extensive clinical experience and the recent approval of Luxturna® (Spark Therapeutics, now Roche) and Zolgensma® (AveXis, now Novartis) place vectors derived from adeno-associated viruses (AAV) among the best options for gene transfer in multiple tissues. Despite these successes, limitations remain to the application of this therapeutic modality in a wider population. AAV was originally identified as a promising virus to derive gene therapy vectors because, despite infecting humans, it was not associated with any evident disease. Thee large proportion of AAV infections in the human population is now revealing as a limitation because after exposure to wild-type AAV, anti-AAV antibodies develops and may neutralize the vectors derived from the virus. Injection of AAV in humans is generally well-tolerated although the immune system can activate after the recognition of AAV vectors capsid and genome. The formation of high-titer neutralizing antibodies to AAV after the first injection precludes vector re-administration. Thus, both pre-existing and post-treatment humoral responses to AAV vectors greatly limit a wider application of this gene transfer modality. Different methods were suggested to overcome this limitation. The extensive preclinical data available and the large clinical experience in the control of AAV vectors immunogenicity are key to clinical translation and to demonstrate the safety and efficacy of these methods and ultimately bring a curative treatment to patients.
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Affiliation(s)
- David-Alexandre Gross
- Genethon, Evry, France.,Université Paris-Saclay, Univ Evry, Inserm, Genethon, Integrare research unit UMR_S951, Evry, France
| | - Novella Tedesco
- Genethon, Evry, France.,Université Paris-Saclay, Univ Evry, Inserm, Genethon, Integrare research unit UMR_S951, Evry, France
| | - Christian Leborgne
- Genethon, Evry, France.,Université Paris-Saclay, Univ Evry, Inserm, Genethon, Integrare research unit UMR_S951, Evry, France
| | - Giuseppe Ronzitti
- Genethon, Evry, France.,Université Paris-Saclay, Univ Evry, Inserm, Genethon, Integrare research unit UMR_S951, Evry, France
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19
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Varin J, Morival C, Maillard N, Adjali O, Cronin T. Risk Mitigation of Immunogenicity: A Key to Personalized Retinal Gene Therapy. Int J Mol Sci 2021; 22:12818. [PMID: 34884622 PMCID: PMC8658027 DOI: 10.3390/ijms222312818] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Revised: 11/17/2021] [Accepted: 11/23/2021] [Indexed: 12/27/2022] Open
Abstract
Gene therapy (GT) for ocular disorders has advanced the most among adeno-associated virus (AAV)-mediated therapies, with one product already approved in the market. The bank of retinal gene mutations carefully compiled over 30 years, the small retinal surface that does not require high clinical vector stocks, and the relatively immune-privileged environment of the eye explain such success. However, adverse effects due to AAV-delivery, though rare in the retina have led to the interruption of clinical trials. Risk mitigation, as the key to safe and efficient GT, has become the focus of 'bedside-back-to-bench' studies. Herein, we overview the inflammatory adverse events described in retinal GT trials and analyze which components of the retinal immunological environment might be the most involved in these immune responses, with a focus on the innate immune system composed of microglial surveillance. We consider the factors that can influence inflammation in the retina after GT such as viral sensors in the retinal tissue and CpG content in promoters or transgene sequences. Finally, we consider options to reduce the immunological risk, including dose, modified capsids or exclusion criteria for clinical trials. A better understanding and mitigation of immune risk factors inducing host immunity in AAV-mediated retinal GT is the key to achieving safe and efficient GT.
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Affiliation(s)
| | | | | | - Oumeya Adjali
- CHU de Nantes, INSERM UMR1089, Translational Gene Therapy for Genetic Diseases, Université de Nantes, F-44200 Nantes, France; (J.V.); (C.M.); (N.M.)
| | - Therese Cronin
- CHU de Nantes, INSERM UMR1089, Translational Gene Therapy for Genetic Diseases, Université de Nantes, F-44200 Nantes, France; (J.V.); (C.M.); (N.M.)
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20
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Rapti K, Grimm D. Adeno-Associated Viruses (AAV) and Host Immunity - A Race Between the Hare and the Hedgehog. Front Immunol 2021; 12:753467. [PMID: 34777364 PMCID: PMC8586419 DOI: 10.3389/fimmu.2021.753467] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Accepted: 09/28/2021] [Indexed: 12/12/2022] Open
Abstract
Adeno-associated viruses (AAV) have emerged as the lead vector in clinical trials and form the basis for several approved gene therapies for human diseases, mainly owing to their ability to sustain robust and long-term in vivo transgene expression, their amenability to genetic engineering of cargo and capsid, as well as their moderate toxicity and immunogenicity. Still, recent reports of fatalities in a clinical trial for a neuromuscular disease, although linked to an exceptionally high vector dose, have raised new caution about the safety of recombinant AAVs. Moreover, concerns linger about the presence of pre-existing anti-AAV antibodies in the human population, which precludes a significant percentage of patients from receiving, and benefitting from, AAV gene therapies. These concerns are exacerbated by observations of cellular immune responses and other adverse events, including detrimental off-target transgene expression in dorsal root ganglia. Here, we provide an update on our knowledge of the immunological and molecular race between AAV (the “hedgehog”) and its human host (the “hare”), together with a compendium of state-of-the-art technologies which provide an advantage to AAV and which, thus, promise safer and more broadly applicable AAV gene therapies in the future.
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Affiliation(s)
- Kleopatra Rapti
- Department of Infectious Diseases/Virology, Medical Faculty, University of Heidelberg, Heidelberg, Germany.,BioQuant Center, BQ0030, University of Heidelberg, Heidelberg, Germany
| | - Dirk Grimm
- Department of Infectious Diseases/Virology, Medical Faculty, University of Heidelberg, Heidelberg, Germany.,BioQuant Center, BQ0030, University of Heidelberg, Heidelberg, Germany.,German Center for Infection Research Deutsches Zentrum für Infektionsforschung (DZIF) and German Center for Cardiovascular Research Deutsches Zentrum für Herz-Kreislauf-Erkrankungen (DZHK), Partner Site Heidelberg, Heidelberg, Germany
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21
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Muhuri M, Maeda Y, Ma H, Ram S, Fitzgerald KA, Tai PW, Gao G. Overcoming innate immune barriers that impede AAV gene therapy vectors. J Clin Invest 2021; 131:143780. [PMID: 33393506 DOI: 10.1172/jci143780] [Citation(s) in RCA: 65] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The field of gene therapy has made considerable progress over the past several years. Adeno-associated virus (AAV) vectors have emerged as promising and attractive tools for in vivo gene therapy. Despite the recent clinical successes achieved with recombinant AAVs (rAAVs) for therapeutics, host immune responses against the vector and transgene product have been observed in numerous preclinical and clinical studies. These outcomes have hampered the advancement of AAV gene therapies, preventing them from becoming fully viable and safe medicines. The human immune system is multidimensional and complex. Both the innate and adaptive arms of the immune system seem to play a concerted role in the response against rAAVs. While most efforts have been focused on the role of adaptive immunity and developing ways to overcome it, the innate immune system has also been found to have a critical function. Innate immunity not only mediates the initial response to the vector, but also primes the adaptive immune system to launch a more deleterious attack against the foreign vector. This Review highlights what is known about innate immune responses against rAAVs and discusses potential strategies to circumvent these pathways.
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Affiliation(s)
- Manish Muhuri
- Horae Gene Therapy Center.,Department of Microbiology and Physiological Systems.,VIDE Program
| | - Yukiko Maeda
- Horae Gene Therapy Center.,VIDE Program.,Department of Medicine
| | | | - Sanjay Ram
- Division of Infectious Diseases and Immunology
| | | | - Phillip Wl Tai
- Horae Gene Therapy Center.,Department of Microbiology and Physiological Systems.,VIDE Program
| | - Guangping Gao
- Horae Gene Therapy Center.,Department of Microbiology and Physiological Systems.,Li Weibo Institute for Rare Diseases Research, University of Massachusetts Medical School, Worcester, Massachusetts, USA
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22
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Emerging Immunogenicity and Genotoxicity Considerations of Adeno-Associated Virus Vector Gene Therapy for Hemophilia. J Clin Med 2021; 10:jcm10112471. [PMID: 34199563 PMCID: PMC8199697 DOI: 10.3390/jcm10112471] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 05/20/2021] [Accepted: 05/24/2021] [Indexed: 12/11/2022] Open
Abstract
Adeno-associated viral (AAV) vector gene therapy has shown promise as a possible cure for hemophilia. However, immune responses directed against AAV vectors remain a hurdle to the broader use of this gene transfer platform. Both innate and adaptive immune responses can affect the safety and efficacy of AAV vector-mediated gene transfer in humans. These immune responses may be triggered by the viral capsid, the vector's nucleic acid payload, or other vector contaminants or excipients, or by the transgene product encoded by the vector itself. Various preclinical and clinical strategies have been explored to overcome the issues of AAV vector immunogenicity and transgene-related immune responses. Although results of these strategies are encouraging, more efficient approaches are needed to deliver safe, predictable, and durable outcomes for people with hemophilia. In addition to durability, long-term follow-up of gene therapy trial participants will allow us to address potential safety concerns related to vector integration. Herein, we describe the challenges with current methodologies to deliver optimal outcomes for people with hemophilia who choose to undergo AAV vector gene therapy and the potential opportunities to improve on the results.
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23
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Bertolini TB, Shirley JL, Zolotukhin I, Li X, Kaisho T, Xiao W, Kumar SRP, Herzog RW. Effect of CpG Depletion of Vector Genome on CD8 + T Cell Responses in AAV Gene Therapy. Front Immunol 2021; 12:672449. [PMID: 34135899 PMCID: PMC8200677 DOI: 10.3389/fimmu.2021.672449] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Accepted: 04/20/2021] [Indexed: 12/12/2022] Open
Abstract
Adeno associated viral (AAV) vectors have emerged as a preferred platform for in vivo gene replacement therapy and represent one of the most promising strategies to treat monogenetic disorders such as hemophilia. However, immune responses to gene transfer have hampered human gene therapy in clinical trials. Over the past decade, it has become clear that innate immune recognition provides signals for the induction of antigen-specific responses against vector or transgene product. In particular, TLR9 recognition of the vector's DNA genome in plasmacytoid dendritic cells (pDCs) has been identified as a key factor. Data from clinical trials and pre-clinical studies implement CpG motifs in the vector genome as drivers of immune responses, especially of CD8+ T cell activation. Here, we demonstrate that cross-priming of AAV capsid-specific CD8+ T cells depends on XCR1+ dendritic cells (which are likely the main cross-presenting cell that cooperates with pDCs to activate CD8+ T cells) and can be minimized by the elimination of CpG motifs in the vector genome. Further, a CpG-depleted vector expressing human coagulation factor IX showed markedly reduced (albeit not entirely eliminated) CD8+ T cell infiltration upon intramuscular gene transfer in hemophilia B mice when compared to conventional CpG+ vector (comprised of native sequences), resulting in better preservation of transduced muscle fibers. Therefore, this deimmunization strategy is helpful in reducing the potential for CD8+ T cell responses to capsid or transgene product. However, CpG depletion had minimal effects on antibody responses against capsid or transgene product, which appear to be largely independent of CpG motifs.
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Affiliation(s)
- Thais B. Bertolini
- Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN, United States
| | - Jamie L. Shirley
- Department Pediatrics, University of Florida, Gainesville, FL, United States
| | - Irene Zolotukhin
- Department Pediatrics, University of Florida, Gainesville, FL, United States
| | - Xin Li
- Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN, United States
| | - Tsuneyasu Kaisho
- Department of Immunology, Institute of Advanced Medicine, Wakayama Medical University, Wakayama, Japan
- Laboratory for Inflammatory Regulation, RIKEN Center for Integrative Medical Sciences, Yokohama, Japan
| | - Weidong Xiao
- Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN, United States
| | - Sandeep R. P. Kumar
- Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN, United States
| | - Roland W. Herzog
- Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN, United States
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24
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Dudek AM, Porteus MH. Answered and Unanswered Questions in Early-Stage Viral Vector Transduction Biology and Innate Primary Cell Toxicity for Ex-Vivo Gene Editing. Front Immunol 2021; 12:660302. [PMID: 34122418 PMCID: PMC8195279 DOI: 10.3389/fimmu.2021.660302] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 05/04/2021] [Indexed: 01/07/2023] Open
Abstract
Adeno-associated virus is a highly efficient DNA delivery vehicle for genome editing strategies that employ CRISPR/Cas9 and a DNA donor for homology-directed repair. Many groups have used this strategy in development of therapies for blood and immune disorders such as sickle-cell anemia and severe-combined immunodeficiency. However, recent events have called into question the immunogenicity of AAV as a gene therapy vector and the safety profile dictated by the immune response to this vector. The target cells dictating this response and the molecular mechanisms dictating cellular response to AAV are poorly understood. Here, we will investigate the current known AAV capsid and genome interactions with cellular proteins during early stage vector transduction and how these interactions may influence innate cellular responses. We will discuss the current understanding of innate immune activation and DNA damage response to AAV, and the limitations of what is currently known. In particular, we will focus on pathway differences in cell line verses primary cells, with a focus on hematopoietic stem and progenitor cells (HSPCs) in the context of ex-vivo gene editing, and what we can learn from HSPC infection by other parvoviruses. Finally, we will discuss how innate immune and DNA damage response pathway activation in these highly sensitive stem cell populations may impact long-term engraftment and clinical outcomes as these gene-editing strategies move towards the clinic, with the aim to propose pathways relevant for improved hematopoietic stem cell survival and long-term engraftment after AAV-mediated genome editing.
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Affiliation(s)
- Amanda Mary Dudek
- Department of Pediatrics, Stanford University, Stanford, CA, United States.,Department of Pediatrics, School of Medicine, Stanford University, Palo Alto, CA, United States
| | - Matthew Hebden Porteus
- Department of Pediatrics, Stanford University, Stanford, CA, United States.,Department of Pediatrics, School of Medicine, Stanford University, Palo Alto, CA, United States
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25
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Chowdhury EA, Meno-Tetang G, Chang HY, Wu S, Huang HW, Jamier T, Chandran J, Shah DK. Current progress and limitations of AAV mediated delivery of protein therapeutic genes and the importance of developing quantitative pharmacokinetic/pharmacodynamic (PK/PD) models. Adv Drug Deliv Rev 2021; 170:214-237. [PMID: 33486008 DOI: 10.1016/j.addr.2021.01.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Revised: 01/13/2021] [Accepted: 01/14/2021] [Indexed: 12/17/2022]
Abstract
While protein therapeutics are one of the most successful class of drug molecules, they are expensive and not suited for treating chronic disorders that require long-term dosing. Adeno-associated virus (AAV) mediated in vivo gene therapy represents a viable alternative, which can deliver the genes of protein therapeutics to produce long-term expression of proteins in target tissues. Ongoing clinical trials and recent regulatory approvals demonstrate great interest in these therapeutics, however, there is a lack of understanding regarding their cellular disposition, whole-body disposition, dose-exposure relationship, exposure-response relationship, and how product quality and immunogenicity affects these important properties. In addition, there is a lack of quantitative studies to support the development of pharmacokinetic-pharmacodynamic models, which can support the discovery, development, and clinical translation of this delivery system. In this review, we have provided a state-of-the-art overview of current progress and limitations related to AAV mediated delivery of protein therapeutic genes, along with our perspective on the steps that need to be taken to improve clinical translation of this therapeutic modality.
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26
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Bulcha JT, Wang Y, Ma H, Tai PWL, Gao G. Viral vector platforms within the gene therapy landscape. Signal Transduct Target Ther 2021; 6:53. [PMID: 33558455 PMCID: PMC7868676 DOI: 10.1038/s41392-021-00487-6] [Citation(s) in RCA: 453] [Impact Index Per Article: 151.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 10/05/2020] [Accepted: 10/23/2020] [Indexed: 01/30/2023] Open
Abstract
Throughout its 40-year history, the field of gene therapy has been marked by many transitions. It has seen great strides in combating human disease, has given hope to patients and families with limited treatment options, but has also been subject to many setbacks. Treatment of patients with this class of investigational drugs has resulted in severe adverse effects and, even in rare cases, death. At the heart of this dichotomous field are the viral-based vectors, the delivery vehicles that have allowed researchers and clinicians to develop powerful drug platforms, and have radically changed the face of medicine. Within the past 5 years, the gene therapy field has seen a wave of drugs based on viral vectors that have gained regulatory approval that come in a variety of designs and purposes. These modalities range from vector-based cancer therapies, to treating monogenic diseases with life-altering outcomes. At present, the three key vector strategies are based on adenoviruses, adeno-associated viruses, and lentiviruses. They have led the way in preclinical and clinical successes in the past two decades. However, despite these successes, many challenges still limit these approaches from attaining their full potential. To review the viral vector-based gene therapy landscape, we focus on these three highly regarded vector platforms and describe mechanisms of action and their roles in treating human disease.
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Affiliation(s)
- Jote T Bulcha
- Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA, USA
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, MA, USA
| | - Yi Wang
- Department of Pathophysiology, West China College of Basic medical sciences & Forensic Medicine, Sichuan University, Chengdu, China
| | - Hong Ma
- Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA, USA
| | - Phillip W L Tai
- Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA, USA.
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, MA, USA.
- VIDE Program, University of Massachusetts Medical School, Worcester, MA, USA.
| | - Guangping Gao
- Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA, USA.
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, MA, USA.
- Li Weibo Institute for Rare Diseases Research, University of Massachusetts Medical School, Worcester, MA, USA.
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27
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Huang L, Wan J, Wu Y, Tian Y, Yao Y, Yao S, Ji X, Wang S, Su Z, Xu H. Challenges in adeno-associated virus-based treatment of central nervous system diseases through systemic injection. Life Sci 2021; 270:119142. [PMID: 33524419 DOI: 10.1016/j.lfs.2021.119142] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 01/22/2021] [Accepted: 01/23/2021] [Indexed: 12/19/2022]
Abstract
Adeno-associated virus (AAV) vector, an excellent gene therapy vector, has been widely used in the treatment of various central nervous system (CNS) diseases. Due to the presence of the blood-brain barrier (BBB), early attempts at AAV-based CNS diseases treatment were mainly performed through intracranial injections. Subsequently, systemic injections of AAV9, the first AAV that was shown to have BBB-crossing ability in newborn and adult mice, were assessed in clinical trials for multiple CNS diseases. However, the development of systemic AAV injections to treat CNS diseases is still associated with many challenges, such as the efficiency of AAV in crossing the BBB, the peripheral toxicity caused by the expression of AAV-delivered genes, and the immune barrier against AAV in the blood. In this review, we will introduce the biology of the AAV vector and the advantages of systemic AAV injections to treat CNS diseases. Most importantly, we will introduce the challenges associated with systemic injection of therapeutic AAV in treating CNS diseases and suggest feasible solutions.
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Affiliation(s)
- Lan Huang
- Department of Immunology, Jiangsu University, Zhenjiang 212013, China
| | - Jie Wan
- Department of Immunology, Jiangsu University, Zhenjiang 212013, China; Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
| | - Yinqiu Wu
- Department of Immunology, Jiangsu University, Zhenjiang 212013, China
| | - Yu Tian
- Department of Immunology, Jiangsu University, Zhenjiang 212013, China
| | - Yizheng Yao
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Shun Yao
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Xiaoyun Ji
- Department of Immunology, Jiangsu University, Zhenjiang 212013, China
| | - Shengjun Wang
- Department of Immunology, Jiangsu University, Zhenjiang 212013, China
| | - Zhaoliang Su
- Department of Immunology, Jiangsu University, Zhenjiang 212013, China
| | - Huaxi Xu
- Department of Immunology, Jiangsu University, Zhenjiang 212013, China.
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28
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Rghei AD, van Lieshout LP, Santry LA, Guilleman MM, Thomas SP, Susta L, Karimi K, Bridle BW, Wootton SK. AAV Vectored Immunoprophylaxis for Filovirus Infections. Trop Med Infect Dis 2020; 5:tropicalmed5040169. [PMID: 33182447 PMCID: PMC7709665 DOI: 10.3390/tropicalmed5040169] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 11/05/2020] [Accepted: 11/06/2020] [Indexed: 01/07/2023] Open
Abstract
Filoviruses are among the deadliest infectious agents known to man, causing severe hemorrhagic fever, with up to 90% fatality rates. The 2014 Ebola outbreak in West Africa resulted in over 28,000 infections, demonstrating the large-scale human health and economic impact generated by filoviruses. Zaire ebolavirus is responsible for the greatest number of deaths to date and consequently there is now an approved vaccine, Ervebo, while other filovirus species have similar epidemic potential and remain without effective vaccines. Recent clinical success of REGN-EB3 and mAb-114 monoclonal antibody (mAb)-based therapies supports further investigation of this treatment approach for other filoviruses. While efficacious, protection from passive mAb therapies is short-lived, requiring repeat dosing to maintain therapeutic concentrations. An alternative strategy is vectored immunoprophylaxis (VIP), which utilizes an adeno-associated virus (AAV) vector to generate sustained expression of selected mAbs directly in vivo. This approach takes advantage of validated mAb development and enables vectorization of the top candidates to provide long-term immunity. In this review, we summarize the history of filovirus outbreaks, mAb-based therapeutics, and highlight promising AAV vectorized approaches to providing immunity against filoviruses where vaccines are not yet available.
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29
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Pierce GF. Uncertainty in an era of transformative therapy for haemophilia: Addressing the unknowns. Haemophilia 2020; 27 Suppl 3:103-113. [PMID: 32484283 DOI: 10.1111/hae.14023] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 03/24/2020] [Indexed: 12/12/2022]
Abstract
Haemophilia is at the dawn of a new era in therapeutic management, one that can generate greater protection from bleeding and a functional cure in some individuals. Prior advances in protein engineering and monoclonal antibody technology have facilitated therapeutic options to maintain decreased risk of bleeding and less burdensome treatment. The use of gene transfer, first proposed in 1971 for monogenic diseases, is emerging as an effective long-term treatment for a variety of diseases. Transfer of functional factor VIII (FVIII) and factor IX (FIX) genes has witnessed a series of advances and setbacks since the first non-clinical experiments in animals were initiated nearly 30 years ago. More recently, multiyear therapeutic levels of FVIII and FIX activity have been achieved in human clinical trials, translated into meaningful clinical benefit and a functional cure. While clinical progress has been definitive, many questions remain unanswered as prelicensure phase 3 clinical trials are underway. These unanswered questions translate into a state of uncertainty about the known unknowns and unknown unknowns intrinsic to any new therapeutic platform. Accepting this modality as a means to functionally cure haemophilia also means accepting the uncertainty regarding the biology of viral vector-mediated gene transfer, which remains inadequately understood. Gene therapy is a far more complex biological 'drug' than small molecule and protein drugs, where manufacturing processes and the drugs themselves are now well characterized. Extent of community acceptance of uncertainty and acknowledgement of the need for an uncompromising drive for answers to the unknowns will characterize the introduction of this first generation of gene therapy for haemophilia to the wider patient population in both resource-rich and resource-poor countries.
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30
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Ronzitti G, Gross DA, Mingozzi F. Human Immune Responses to Adeno-Associated Virus (AAV) Vectors. Front Immunol 2020; 11:670. [PMID: 32362898 PMCID: PMC7181373 DOI: 10.3389/fimmu.2020.00670] [Citation(s) in RCA: 158] [Impact Index Per Article: 39.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Accepted: 03/24/2020] [Indexed: 12/24/2022] Open
Abstract
Recombinant adeno-associated virus (rAAV) vectors are one of the most promising in vivo gene delivery tools. Several features make rAAV vectors an ideal platform for gene transfer. However, the high homology with the parental wild-type virus, which often infects humans, poses limitations in terms of immune responses associated with this vector platform. Both humoral and cell-mediated immunity to wild-type AAV have been documented in healthy donors, and, at least in the case of anti-AAV antibodies, have been shown to have a potentially high impact on the outcome of gene transfer. While several factors can contribute to the overall immunogenicity of rAAV vectors, vector design and the total vector dose appear to be responsible of immune-mediated toxicities. While preclinical models have been less than ideal in predicting the outcome of gene transfer in humans, the current preclinical body of evidence clearly demonstrates that rAAV vectors can trigger both innate and adaptive immune responses. Data gathered from clinical trials offers key learnings on the immunogenicity of AAV vectors, highlighting challenges as well as the potential strategies that could help unlock the full therapeutic potential of in vivo gene transfer.
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Affiliation(s)
- Giuseppe Ronzitti
- INTEGRARE, Genethon, Inserm, Univ Evry, Université Paris-Saclay, Evry, France
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31
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Verdera HC, Kuranda K, Mingozzi F. AAV Vector Immunogenicity in Humans: A Long Journey to Successful Gene Transfer. Mol Ther 2020; 28:723-746. [PMID: 31972133 PMCID: PMC7054726 DOI: 10.1016/j.ymthe.2019.12.010] [Citation(s) in RCA: 326] [Impact Index Per Article: 81.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Accepted: 12/27/2019] [Indexed: 12/15/2022] Open
Abstract
Gene therapy with adeno-associated virus (AAV) vectors has demonstrated safety and long-term efficacy in a number of trials across target organs, including eye, liver, skeletal muscle, and the central nervous system. Since the initial evidence that AAV vectors can elicit capsid T cell responses in humans, which can affect the duration of transgene expression, much progress has been made in understanding and modulating AAV vector immunogenicity. It is now well established that exposure to wild-type AAV results in priming of the immune system against the virus, with development of both humoral and T cell immunity. Aside from the neutralizing effect of antibodies, the impact of pre-existing immunity to AAV on gene transfer is still poorly understood. Herein, we review data emerging from clinical trials across a broad range of gene therapy applications. Common features of immune responses to AAV can be found, suggesting, for example, that vector immunogenicity is dose-dependent, and that innate immunity plays an important role in the outcome of gene transfer. A range of host-specific factors are also likely to be important, and a comprehensive understanding of the mechanisms driving AAV vector immunogenicity in humans will be key to unlocking the full potential of in vivo gene therapy.
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Affiliation(s)
- Helena Costa Verdera
- Genethon and INSERM U951, 91000 Evry, France; Sorbonne Université and INSERM U974, 75013 Paris, France
| | | | - Federico Mingozzi
- Genethon and INSERM U951, 91000 Evry, France; Spark Therapeutics, Philadelphia, PA 19104, USA.
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32
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Abstract
Several viral vector-based gene therapy drugs have now received marketing approval. A much larger number of additional viral vectors are in various stages of clinical trials for the treatment of genetic and acquired diseases, with many more in pre-clinical testing. Efficiency of gene transfer and ability to provide long-term therapy make these vector systems very attractive. In fact, viral vector gene therapy has been able to treat or even cure diseases for which there had been no or only suboptimal treatments. However, innate and adaptive immune responses to these vectors and their transgene products constitute substantial hurdles to clinical development and wider use in patients. This review provides an overview of the type of immune responses that have been documented in animal models and in humans who received gene transfer with one of three widely tested vector systems, namely adenoviral, lentiviral, or adeno-associated viral vectors. Particular emphasis is given to mechanisms leading to immune responses, efforts to reduce vector immunogenicity, and potential solutions to the problems. At the same time, we point out gaps in our knowledge that should to be filled and problems that need to be addressed going forward.
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Affiliation(s)
- Jamie L Shirley
- Gene Therapy Center, University of Massachusetts, Worchester, MA, USA
| | - Ype P de Jong
- Division of Gastroenterology and Hepatology, Weill Cornell Medicine, New York, NY, USA
| | - Cox Terhorst
- Division of Immunology, Beth Israel Deaconess Medical Center (BIDMC), Harvard Medical School, Boston, MA, USA
| | - Roland W Herzog
- Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN, USA.
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Immune Response Mechanisms against AAV Vectors in Animal Models. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2019; 17:198-208. [PMID: 31970198 PMCID: PMC6965504 DOI: 10.1016/j.omtm.2019.12.008] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Early preclinical studies in rodents and other species did not reveal that vector or transgene immunity would present a significant hurdle for sustained gene expression. While there was early evidence of mild immune responses to adeno-associated virus (AAV) in preclinical studies, it was generally believed that these responses were too weak and transient to negatively impact sustained transduction. However, translation of the cumulative success in treating hemophilia B in rodents and dogs with an AAV2-F9 vector to human studies was not as successful. Despite significant progress in recent clinical trials for hemophilia, new immunotoxicities to AAV and transgene are emerging in humans that require better animal models to assess and overcome these responses. The animal models designed to address these immune complications have provided critical information to assess how vector dose, vector capsid processing, vector genome, difference in serotypes, and variations in vector delivery route can impact immunity and to develop approaches for overcoming pre-existing immunity. Additionally, a comprehensive dissection of innate, adaptive, and regulatory responses to AAV vectors in preclinical studies has provided a framework that can be utilized for development of immunomodulatory therapies to overcome or bypass immune responses and for developing strategic approaches toward engineering stealth AAV vectors that can circumvent immunity.
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34
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Nidetz NF, McGee MC, Tse LV, Li C, Cong L, Li Y, Huang W. Adeno-associated viral vector-mediated immune responses: Understanding barriers to gene delivery. Pharmacol Ther 2019; 207:107453. [PMID: 31836454 DOI: 10.1016/j.pharmthera.2019.107453] [Citation(s) in RCA: 92] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Accepted: 11/26/2019] [Indexed: 02/06/2023]
Abstract
Adeno-associated viral (AAV) vectors have emerged as the leading gene delivery platform for gene therapy and vaccination. Three AAV-based gene therapy drugs, Glybera, LUXTURNA, and ZOLGENSMA were approved between 2012 and 2019 by the European Medicines Agency and the United States Food and Drug Administration as treatments for genetic diseases hereditary lipoprotein lipase deficiency (LPLD), inherited retinal disease (IRD), and spinal muscular atrophy (SMA), respectively. Despite these therapeutic successes, clinical trials have demonstrated that host anti-viral immune responses can prevent the long-term gene expression of AAV vector-encoded genes. Therefore, it is critical that we understand the complex relationship between AAV vectors and the host immune response. This knowledge could allow for the rational design of optimized gene transfer vectors capable of either subverting host immune responses in the context of gene therapy applications, or stimulating desirable immune responses that generate protective immunity in vaccine applications to AAV vector-encoded antigens. This review provides an overview of our current understanding of the AAV-induced immune response and discusses potential strategies by which these responses can be manipulated to improve AAV vector-mediated gene transfer.
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Affiliation(s)
- Natalie F Nidetz
- Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Michael C McGee
- Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Longping V Tse
- Department of Epidemiology, School of Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Chengwen Li
- Gene Therapy Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Le Cong
- Department of Pathology and Department of Genetics, School of Medicine, Stanford University, Stanford, CA 94305, USA
| | - Yunxing Li
- Department of Molecular Medicine, Cornell University, Ithaca, NY 14853, USA
| | - Weishan Huang
- Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803, USA; Department of Microbiology and Immunology, Cornell University, Ithaca, NY 14853, USA.
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35
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Xiang Z, Kurupati RK, Li Y, Kuranda K, Zhou X, Mingozzi F, High KA, Ertl HCJ. The Effect of CpG Sequences on Capsid-Specific CD8 + T Cell Responses to AAV Vector Gene Transfer. Mol Ther 2019; 28:771-783. [PMID: 31839483 DOI: 10.1016/j.ymthe.2019.11.014] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Revised: 11/06/2019] [Accepted: 11/11/2019] [Indexed: 12/21/2022] Open
Abstract
Transfer of genes by adeno-associated virus (AAV) vectors is benefiting patients with particular genetic defects. Challenges remain by rejection of AAV-transduced cells, which may be caused by CD8+ T lymphocytes directed to AAV capsid antigens. Reducing the number of CpG motifs from the genome of AAV vectors reduces expansion of naive T cells directed against an epitope within the capsid. In contrast, AAV capsid-specific memory CD8+ T cells respond more vigorously to AAV vectors lacking CpG motifs than to those with CpG motifs presumably reflecting dampening of T cell expansion by cytokines from the innate immune system. Depending on the purification method, AAV vector preparations can contain substantial amounts of empty AAV particles that failed to package the genome. Others have used empty particles as decoys to AAV-neutralizing antibodies. We tested if empty AAV vectors given alone or mixed with genome-containing AAV vectors induce proliferation of naive or memory CD8+ T cells directed to an antigen within an AAV capsid. Naive CD8+ T cells failed to respond to empty AAV vectors, which in contrast induced expansion of AAV-specific memory CD8+ T cells.
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Affiliation(s)
| | | | - Yan Li
- Wistar Institute, Philadelphia, PA 19104, USA
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36
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Shirley JL, Keeler GD, Sherman A, Zolotukhin I, Markusic DM, Hoffman BE, Morel LM, Wallet MA, Terhorst C, Herzog RW. Type I IFN Sensing by cDCs and CD4 + T Cell Help Are Both Requisite for Cross-Priming of AAV Capsid-Specific CD8 + T Cells. Mol Ther 2019; 28:758-770. [PMID: 31780366 DOI: 10.1016/j.ymthe.2019.11.011] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 11/06/2019] [Accepted: 11/07/2019] [Indexed: 12/23/2022] Open
Abstract
Adeno-associated virus (AAV) vectors are widely used in clinical gene therapy to correct genetic disease by in vivo gene transfer. Although the vectors are useful, in part because of their limited immunogenicity, immune responses directed at vector components have complicated applications in humans. These include, for instance, innate immune sensing of vector components by plasmacytoid dendritic cells (pDCs), which sense the vector DNA genome via Toll-like receptor 9. Adaptive immune responses employ antigen presentation by conventional dendritic cells (cDCs), which leads to cross-priming of capsid-specific CD8+ T cells. In this study, we sought to determine the mechanisms that promote licensing of cDCs, which is requisite for CD8+ T cell activation. Blockage of type 1 interferon (T1 IFN) signaling by monoclonal antibody therapy prevented cross-priming. Furthermore, experiments in cell-type-restricted knockout mice showed a specific requirement for the receptor for T1 IFN (IFNaR) in cDCs. In contrast, natural killer (NK) cells are not needed, indicating a direct rather than indirect effect of T1 IFN on cDCs. In addition, co-stimulation by CD4+ T cells via CD40-CD40L was required for cross-priming, and blockage of co-stimulation but not of T1 IFN additionally reduced antibody formation against capsid. These mechanistic insights inform the development of targeted immune interventions.
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Affiliation(s)
- Jamie L Shirley
- Department Pediatrics, University of Florida, Gainesville, FL, USA
| | | | | | - Irene Zolotukhin
- Department Pediatrics, University of Florida, Gainesville, FL, USA
| | - David M Markusic
- Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Brad E Hoffman
- Department Pediatrics, University of Florida, Gainesville, FL, USA
| | - Laurence M Morel
- Department of Pathology, Immunology and Laboratory Medicine, University of Florida, Gainesville, FL, USA
| | - Mark A Wallet
- Department of Pathology, Immunology and Laboratory Medicine, University of Florida, Gainesville, FL, USA
| | - Cox Terhorst
- Division of Immunology, Beth Israel Deaconess Medical Center (BIDMC), Harvard Medical School, Boston, MA, USA
| | - Roland W Herzog
- Department Pediatrics, University of Florida, Gainesville, FL, USA; Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN, USA.
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Khatib TZ, Martin KR. Neuroprotection in Glaucoma: Towards Clinical Trials and Precision Medicine. Curr Eye Res 2019; 45:327-338. [PMID: 31475591 DOI: 10.1080/02713683.2019.1663385] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Purpose: The eye is currently at the forefront of translational medicine and therapeutics. However, despite advances in technology, primary open-angle glaucoma remains the leading cause of irreversible blindness worldwide. Traditional intraocular pressure (IOP)-lowering therapies are often not sufficient to prevent progression to blindness, even in patients with access to high-quality healthcare. Neuroprotection strategies, which aim to boost the ability of target cells to withstand a pathological insult, have shown significant promise in animal models but none have shown clinically relevant efficacy in human clinical trials to date. We sought to evaluate the current status of neuroprotection clinical trials for glaucoma and identify limitations which have prevented translation of new glaucoma therapies to date.Methods: Literature searches identified English language references. Sources included MEDLINE, EMBASE, the Cochrane Library and Web of Science databases; reference lists of retrieved studies; and internet pages of relevant organisations, meetings and conference proceedings, and clinical trial registries.Results: We discuss six key neuroprotective strategies for glaucoma that have reached the clinical trial stage. Delivery of neurotrophic factors through gene therapy is also progressing towards glaucoma clinical trials. Refinements in trial design and the use of new modalities to define structural and functional endpoints may improve our assessment of disease activity and treatment efficacy. Advances in our understanding of compartmentalised glaucomatous degeneration and continued progress in the molecular profiling of glaucoma patients will enable us to predict individual risk and tailor treatment.Conclusion: New approaches to future glaucoma neuroprotection trials could improve the prospects for new glaucoma therapies. Glaucoma treatment tailored according to an individual's unique risk profile may become increasingly common in the future.
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Affiliation(s)
- Tasneem Z Khatib
- John Van Geest Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK.,Eye Department, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK.,Medical Sciences Division, University of Oxford, Oxford, UK
| | - Keith R Martin
- John Van Geest Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK.,Eye Department, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK.,Cambridge NIHR Biomedical Research Centre, Cambridge, UK.,Wellcome Trust - 5 MRC Cambridge Stem Cell Institute, University of Cambridge, Cambridge, UK.,Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, Australia.,Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Australia
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38
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Da Rocha S, Bigot J, Onodi F, Cosette J, Corre G, Poupiot J, Fenard D, Gjata B, Galy A, Neildez-Nguyen TMA. Temporary Reduction of Membrane CD4 with the Antioxidant MnTBAP Is Sufficient to Prevent Immune Responses Induced by Gene Transfer. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2019; 14:285-299. [PMID: 31497619 PMCID: PMC6718808 DOI: 10.1016/j.omtm.2019.06.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Accepted: 06/29/2019] [Indexed: 12/14/2022]
Abstract
Unexpectedly, the synthetic antioxidant MnTBAP was found to cause a rapid and reversible downregulation of CD4 on T cells in vitro and in vivo. This effect resulted from the internalization of membrane CD4 T cell molecules into clathrin-coated pits and involved disruption of the CD4/p56Lck complex. The CD4 deprivation induced by MnTBAP had functional consequences on CD4-dependent infectious processes or immunological responses as shown in various models, including gene therapy. In cultured human T cells, MnTBAP-induced downregulation of CD4 functionally suppressed gp120- mediated lentiviral transduction in a model relevant for HIV infection. The injection of MnTBAP in mice reduced membrane CD4 on lymphocytes in vivo within 5 days of treatment, preventing OVA peptide T cell immunization while allowing subsequent immunization once treatment was stopped. In a mouse gene therapy model, MnTBAP treatment at the time of adenovirus-associated virus (AAV) vector administration, successfully controlled the induction of anti-transgene and anti-capsid immune responses mediated by CD4+ T cells, enabling the redosing mice with the same vector. These functional data provide new avenues to develop alternative therapeutic immunomodulatory strategies based on temporary regulation of CD4. These could be particularly useful for AAV gene therapy in which novel strategies for redosing are needed.
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Affiliation(s)
- Sylvie Da Rocha
- Ecole Pratique des Hautes Etudes, PSL Research University, INTEGRARE UMR_S951, INSERM, Généthon, Univ-Evry, 91002 Evry, France
| | - Jérémy Bigot
- Ecole Pratique des Hautes Etudes, PSL Research University, INTEGRARE UMR_S951, INSERM, Généthon, Univ-Evry, 91002 Evry, France
| | - Fanny Onodi
- Ecole Pratique des Hautes Etudes, PSL Research University, INTEGRARE UMR_S951, INSERM, Généthon, Univ-Evry, 91002 Evry, France
| | | | - Guillaume Corre
- Ecole Pratique des Hautes Etudes, PSL Research University, INTEGRARE UMR_S951, INSERM, Généthon, Univ-Evry, 91002 Evry, France
| | - Jérôme Poupiot
- Ecole Pratique des Hautes Etudes, PSL Research University, INTEGRARE UMR_S951, INSERM, Généthon, Univ-Evry, 91002 Evry, France
| | - David Fenard
- Ecole Pratique des Hautes Etudes, PSL Research University, INTEGRARE UMR_S951, INSERM, Généthon, Univ-Evry, 91002 Evry, France
| | | | - Anne Galy
- Ecole Pratique des Hautes Etudes, PSL Research University, INTEGRARE UMR_S951, INSERM, Généthon, Univ-Evry, 91002 Evry, France
| | - Thi My Anh Neildez-Nguyen
- Ecole Pratique des Hautes Etudes, PSL Research University, INTEGRARE UMR_S951, INSERM, Généthon, Univ-Evry, 91002 Evry, France
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39
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Butterfield JS, Biswas M, Shirley JL, Kumar SR, Sherman A, Terhorst C, Ling C, Herzog RW. TLR9-Activating CpG-B ODN but Not TLR7 Agonists Triggers Antibody Formation to Factor IX in Muscle Gene Transfer. Hum Gene Ther Methods 2019; 30:81-92. [PMID: 31140323 PMCID: PMC6590725 DOI: 10.1089/hgtb.2019.013] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Accepted: 05/20/2019] [Indexed: 02/07/2023] Open
Abstract
Innate immune signals that promote B cell responses in gene transfer are generally ill-defined. In this study, we evaluate the effect of activating endosomal Toll-like receptors 7, 8, and 9 (TLR7, TLR7/8, and TLR9) on antibody formation during muscle-directed gene therapy with adeno-associated virus (AAV) vectors. We examined whether activation of endosomal TLRs, by adenine analog CL264 (TLR7 agonist), imidazolquinolone compound R848 (TLR7/8 agonist), or class B CpG oligodeoxynucleotides ODN1826 (TLR9 agonist), could augment antibody formation upon intramuscular administration of AAV1 expressing human clotting factor IX (AAV1-hFIX) in mice. The TLR9 agonist robustly enhanced antibody formation by the 1st week, thus initially eliminating systemic hFIX expression. By contrast, the TLR7 and TLR7/8 agonists did not markedly promote antibody formation, or significantly reduce circulating hFIX. We concurrently investigated the effects of these TLR agonists during muscle gene transfer on mature B cells and dendritic cells (DCs) in the draining lymph nodes including conventional DCs (CD11b+ or CD8α+ cDCs), monocyte-derived dendritic cells (moDCs), and plasmacytoid dendritic cells (pDCs). Only TLR9 stimulation caused a striking increase in the frequency of moDCs within 24 h. The TLR7/8 and TLR9 agonists activated pDCs, both subsets of cDCs, and mature B cells, whereas the TLR7 agonist had only mild effects on these cells. Thus, these TLR ligands have distinct effects on DCs and mature B cells, yet only the TLR9 agonist enhanced the humoral immune response against AAV-expressed hFIX. These new findings indicate a unique ability of certain TLR9 agonists to stimulate B cell responses in muscle gene transfer through enrichment of moDCs.
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Affiliation(s)
| | - Moanaro Biswas
- Department of Pediatrics, University of Florida, Gainesville, Florida
- Department of Pediatrics, Indiana University, Indianapolis, Indiana
| | - Jamie L. Shirley
- Department of Pediatrics, University of Florida, Gainesville, Florida
| | - Sandeep R.P. Kumar
- Department of Pediatrics, Indiana University, Indianapolis, Indiana
- Herman B Wells Center for Pediatric Research, IAPUI, Indianapolis, Indiana
| | - Alexandra Sherman
- Department of Pediatrics, Indiana University, Indianapolis, Indiana
- Herman B Wells Center for Pediatric Research, IAPUI, Indianapolis, Indiana
| | - Cox Terhorst
- Division of Immunology, Beth Israel Deaconess Medical Center (BIDMC), Harvard Medical School, Boston, Massachusetts
| | - Chen Ling
- Department of Pediatrics, University of Florida, Gainesville, Florida
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Roland W. Herzog
- Department of Pediatrics, University of Florida, Gainesville, Florida
- Department of Pediatrics, Indiana University, Indianapolis, Indiana
- Herman B Wells Center for Pediatric Research, IAPUI, Indianapolis, Indiana
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40
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Sauter IP, Madrid KG, de Assis JB, Sá-Nunes A, Torrecilhas AC, Staquicini DI, Pasqualini R, Arap W, Cortez M. TLR9/MyD88/TRIF signaling activates host immune inhibitory CD200 in Leishmania infection. JCI Insight 2019; 4:126207. [PMID: 31092731 DOI: 10.1172/jci.insight.126207] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Accepted: 04/11/2019] [Indexed: 02/06/2023] Open
Abstract
Virulent protozoans named Leishmania in tropical and subtropical areas produce devastating diseases by exploiting host immune responses. Amastigotes of Leishmania amazonensis stimulate macrophages to express CD200, an immunomodulatory ligand, which binds to its cognate receptor (CD200R) and inhibits the inducible nitric oxide synthase and nitric oxide (iNOS/NO) signaling pathways, thereby promoting intracellular survival. However, the mechanisms underlying CD200 induction in macrophages remain largely unknown. Here, we show that phagocytosis-mediated internalization of L. amazonensis amastigotes following activation of endosomal TLR9/MyD88/TRIF signaling is critical for inducing CD200 in infected macrophages. We also demonstrate that Leishmania microvesicles containing DNA fragments activate TLR9-dependent CD200 expression, which inhibits the iNOS/NO pathway and modulates the course of L. amazonensis infection in vivo. These findings demonstrate that Leishmania exploits TLR-signaling pathways not only to inhibit macrophage microbicidal function, but also to evade host systemic immune responses, which has many implications in the severity of the disease.
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Affiliation(s)
| | | | - Josiane B de Assis
- Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Anderson Sá-Nunes
- Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Ana C Torrecilhas
- Department of Pharmaceutical Sciences, Federal University of São Paulo, São Paulo, Brazil
| | - Daniela I Staquicini
- Rutgers Cancer Institute of New Jersey and Division of Cancer Biology, Department of Radiation Oncology, Rutgers New Jersey Medical School, Newark, New Jersey, USA
| | - Renata Pasqualini
- Rutgers Cancer Institute of New Jersey and Division of Cancer Biology, Department of Radiation Oncology, Rutgers New Jersey Medical School, Newark, New Jersey, USA
| | - Wadih Arap
- Rutgers Cancer Institute of New Jersey and Division of Hematology/Oncology, Department of Medicine, Rutgers New Jersey Medical School, Newark, New Jersey, USA
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41
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Kuranda K, Jean-Alphonse P, Leborgne C, Hardet R, Collaud F, Marmier S, Costa Verdera H, Ronzitti G, Veron P, Mingozzi F. Exposure to wild-type AAV drives distinct capsid immunity profiles in humans. J Clin Invest 2018; 128:5267-5279. [PMID: 30352429 DOI: 10.1172/jci122372] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Accepted: 09/11/2018] [Indexed: 01/10/2023] Open
Abstract
Recombinant adeno-associated virus (AAV) vectors have been broadly adopted as a gene delivery tool in clinical trials, owing to their high efficiency of transduction of several host tissues and their low immunogenicity. However, a considerable proportion of the population is naturally exposed to the WT virus from which AAV vectors are derived, which leads to the acquisition of immunological memory that can directly determine the outcome of gene transfer. Here, we show that prior exposure to AAV drives distinct capsid immunity profiles in healthy subjects. In peripheral blood mononuclear cells (PBMCs) isolated from AAV-seropositive donors, recombinant AAV triggered TNF-α secretion in memory CD8+ T cells, B cell differentiation into antibody-secreting cells, and anti-capsid antibody production. Conversely, PBMCs isolated from AAV-seronegative individuals appeared to carry a population of NK cells reactive to AAV. Further, we demonstrated that the AAV capsid activates IL-1β and IL-6 cytokine secretion in monocyte-related dendritic cells (moDCs). IL-1β and IL-6 blockade inhibited the anti-capsid humoral response in vitro and in vivo. These results provide insights into immune responses to AAV in humans, define a possible role for moDCs and NK cells in capsid immunity, and open new avenues for the modulation of vector immunogenicity.
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Affiliation(s)
| | | | | | | | | | | | | | - Giuseppe Ronzitti
- Genethon, Evry, France.,INSERM S951, Université Evry, Université Paris Saclay, EPHE, Evry, France
| | | | - Federico Mingozzi
- INSERM U974, Sorbonne Université, Paris, France.,Genethon, Evry, France.,INSERM S951, Université Evry, Université Paris Saclay, EPHE, Evry, France
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42
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Naso MF, Tomkowicz B, Perry WL, Strohl WR. Adeno-Associated Virus (AAV) as a Vector for Gene Therapy. BioDrugs 2018; 31:317-334. [PMID: 28669112 PMCID: PMC5548848 DOI: 10.1007/s40259-017-0234-5] [Citation(s) in RCA: 683] [Impact Index Per Article: 113.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
There has been a resurgence in gene therapy efforts that is partly fueled by the identification and understanding of new gene delivery vectors. Adeno-associated virus (AAV) is a non-enveloped virus that can be engineered to deliver DNA to target cells, and has attracted a significant amount of attention in the field, especially in clinical-stage experimental therapeutic strategies. The ability to generate recombinant AAV particles lacking any viral genes and containing DNA sequences of interest for various therapeutic applications has thus far proven to be one of the safest strategies for gene therapies. This review will provide an overview of some important factors to consider in the use of AAV as a vector for gene therapy.
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Affiliation(s)
- Michael F Naso
- Janssen Research and Development, 200 McKean Road, Spring House, PA, 19477, USA.
| | - Brian Tomkowicz
- Janssen Research and Development, 200 McKean Road, Spring House, PA, 19477, USA
| | - William L Perry
- Janssen Research and Development, 200 McKean Road, Spring House, PA, 19477, USA
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43
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Abstract
In recent years, the number of clinical trials in which adeno-associated virus (AAV) vectors have been used for in vivo gene transfer has steadily increased. The excellent safety profile, together with the high efficiency of transduction of a broad range of target tissues, has established AAV vectors as the platform of choice for in vivo gene therapy. Successful application of the AAV technology has also been achieved in the clinic for a variety of conditions, including coagulation disorders, inherited blindness, and neurodegenerative diseases, among others. Clinical translation of novel and effective "therapeutic products" is, however, a long process that involves several cycles of iterations from bench to bedside that are required to address issues encountered during drug development. For the AAV vector gene transfer technology, several hurdles have emerged in both preclinical studies and clinical trials; addressing these issues will allow in the future to expand the scope of AAV gene transfer as a therapeutic modality for a variety of human diseases. In this review, we will give an overview on the biology of AAV vector, discuss the design of AAV-based gene therapy strategies for in vivo applications, and present key achievements and emerging issues in the field. We will use the liver as a model target tissue for gene transfer based on the large amount of data available from preclinical and clinical studies.
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Affiliation(s)
- Pasqualina Colella
- Genethon, INSERM U951 INTEGRARE, University of Evry, University Paris-Saclay, 91001 Evry, France
| | - Giuseppe Ronzitti
- Genethon, INSERM U951 INTEGRARE, University of Evry, University Paris-Saclay, 91001 Evry, France
| | - Federico Mingozzi
- Genethon, INSERM U951 INTEGRARE, University of Evry, University Paris-Saclay, 91001 Evry, France
- University Pierre and Marie Curie-Paris 6 and INSERM U974, 75651 Paris, France
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44
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Anchim A, Raddi N, Zig L, Perrieau P, Le Goffic R, Ryffel B, Benihoud K. Humoral Responses Elicited by Adenovirus Displaying Epitopes Are Induced Independently of the Infection Process and Shaped by the Toll-Like Receptor/MyD88 Pathway. Front Immunol 2018; 9:124. [PMID: 29459860 PMCID: PMC5807684 DOI: 10.3389/fimmu.2018.00124] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 01/16/2018] [Indexed: 01/07/2023] Open
Abstract
The use of serotype 5 adenovirus (Ad)-derived vectors in vaccination is confronted to preexisting anti-Ad immunity. Epitope display on Ad capsid is currently being investigated as an alternative approach of vaccination. The present study seeks to better understand virus- and host-related factors controlling the efficacy of this new vaccination approach. In contrast to an Ad vector expressing ovalbumin as a transgene, Ad displaying an ovalbumin-derived B-cell epitope inserted into the fiber protein was able to elicit antibody responses in both Ad-naive and Ad-immune mice. Moreover, introduction of a set of mutations abrogating Ad interaction with its receptors did not modify the virus capacity to elicit a humoral response against the inserted epitope while reducing its capacity to mount antibody responses against the transgene product. Taken as a whole these data indicate that the efficacy of Ad displaying epitopes requires neither Ad binding to its receptors nor the infection process. In addition, the use of genetically deficient mice demonstrated that both toll-like receptor (TLR)/MyD88 and RIG-I/mitochondrial antiviral-signaling (MAVS) innate immunity pathways were dispensable to mount anti-epitope antibody responses. However, they also revealed that TLR/MyD88 pathway but not RIG-I/MAVS pathway controls the nature of antibodies directed against the displayed epitope.
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Affiliation(s)
- Aleksandra Anchim
- Vectorologie et thérapeutiques anticancéreuses, UMR 8203, CNRS, Univ. Paris-Sud, Gustave Roussy, Université Paris-Saclay, Villejuif, France
| | - Najat Raddi
- Vectorologie et thérapeutiques anticancéreuses, UMR 8203, CNRS, Univ. Paris-Sud, Gustave Roussy, Université Paris-Saclay, Villejuif, France
| | - Lena Zig
- Vectorologie et thérapeutiques anticancéreuses, UMR 8203, CNRS, Univ. Paris-Sud, Gustave Roussy, Université Paris-Saclay, Villejuif, France
| | - Patrick Perrieau
- Vectorologie et thérapeutiques anticancéreuses, UMR 8203, CNRS, Univ. Paris-Sud, Gustave Roussy, Université Paris-Saclay, Villejuif, France
| | | | - Bernhard Ryffel
- Experimental and Molecular Immunology and Neurogenetics, UMR 7355, CNRS-University of Orléans, Orléans, France.,Institute of Infectious Diseases and Molecular Medicine (IDM), Cape Town, South Africa
| | - Karim Benihoud
- Vectorologie et thérapeutiques anticancéreuses, UMR 8203, CNRS, Univ. Paris-Sud, Gustave Roussy, Université Paris-Saclay, Villejuif, France
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45
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Ertl HCJ. Preclinical models to assess the immunogenicity of AAV vectors. Cell Immunol 2017; 342:103722. [PMID: 29195742 DOI: 10.1016/j.cellimm.2017.11.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Revised: 11/08/2017] [Accepted: 11/19/2017] [Indexed: 02/07/2023]
Abstract
Although gene transfer using adeno-associated virus (AAV) vectors has made tremendous progress in recent years, challenges remain due to vector-specific adaptive immune responses. Specifically, AAV-neutralizing antibodies reduce AAV-transduction rates, while CD8+ T cells directed to AAV capsid antigens cause rejection of AAV-transduced cells. This has been addressed clinically by excluding humans with pre-existing AAV-neutralizing antibodies from gene transfer trials or by using immunosuppression or reduced doses of vectors expressing improved transgene products to blunt or circumvent destructive T cell responses. Although these approaches have met with success for treatment of some diseases, most notably hemophilia B, they may not be suitable for others. Pre-clinical models are thus needed to test alternative options to sidestep pre-existing AAV-neutralizing antibodies, to prevent their induction following gene transfer and to block the detrimental effects of CD8+ T cells directed to AAV capsid antigens. This chapter describes some of the available, although not yet perfect, models that can assess immune responses to AAV gene transfer.
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46
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Herzog RW, Cooper M, Perrin GQ, Biswas M, Martino AT, Morel L, Terhorst C, Hoffman BE. Regulatory T cells and TLR9 activation shape antibody formation to a secreted transgene product in AAV muscle gene transfer. Cell Immunol 2017; 342:103682. [PMID: 28888664 DOI: 10.1016/j.cellimm.2017.07.012] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 06/15/2017] [Accepted: 07/31/2017] [Indexed: 12/21/2022]
Abstract
Adeno-associated viral (AAV) gene delivery to skeletal muscle is being explored for systemic delivery of therapeutic proteins. To better understand the signals that govern antibody formation against secreted transgene products in this approach, we administered an intramuscular dose of AAV1 vector expressing human coagulation factor IX (hFIX), which does not cause antibody formation against hFIX in C57BL/6 mice. Interestingly, co-administration of a TLR9 agonist (CpG-deoxyoligonucleotide, ODN) but not of lipopolysaccharide, caused a transient anti-hFIX response. ODN activated monocyte-derived dendritic cells and enhanced T follicular helper cell responses. While depletion of regulatory T cells (Tregs) also caused an antibody response, TLR9 activation combined with Treg depletion instead resulted in prolonged CD8+ T cell infiltration of transduced muscle. Thus, Tregs modulate the response to the TLR9 agonist. Further, Treg re-population eventually resolved humoral and cellular immune responses. Therefore, specific modes of TLR9 activation and Tregs orchestrate antibody formation in muscle gene transfer.
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Affiliation(s)
- Roland W Herzog
- Department of Pediatrics, Division of Cellular and Molecular Therapy, University of Florida, Gainesville, FL, United States.
| | - Mario Cooper
- Department of Pediatrics, Division of Cellular and Molecular Therapy, University of Florida, Gainesville, FL, United States
| | - George Q Perrin
- Department of Pediatrics, Division of Cellular and Molecular Therapy, University of Florida, Gainesville, FL, United States
| | - Moanaro Biswas
- Department of Pediatrics, Division of Cellular and Molecular Therapy, University of Florida, Gainesville, FL, United States
| | - Ashley T Martino
- Department of Pediatrics, Division of Cellular and Molecular Therapy, University of Florida, Gainesville, FL, United States
| | - Laurence Morel
- Department of Pathology, Immunology, and Laboratory Investigation, University of Florida, Gainesville, FL, United States
| | - Cox Terhorst
- Division of Immunology, BIDMC, Harvard Medical School, Boston, MA, United States
| | - Brad E Hoffman
- Department of Pediatrics, Division of Cellular and Molecular Therapy, University of Florida, Gainesville, FL, United States.
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47
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Abstract
After two decades of research, in vivo gene transfer with adeno-associated viral (AAV) vectors has now resulted in successful treatments and even cures for several human diseases. However, the potential for immune responses against the therapeutic gene products remains one of the concerns as this approach is broadened to more patients, diverse diseases, and target organs. Immune responses following gene transfer of coagulation factor IX (FIX) for the treatment of the bleeding disorder hemophilia B has been extensively investigated in multiple animal models. Findings from these studies have not only influenced clinical trial design but have broader implications for other diseases. The impact of vector design and dose, as well as target organ/route of administration on humoral and cellular immune responses are reviewed. Furthermore, the potential for tolerance induction by hepatic gene transfer or combination with immune modulation is discussed.
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Affiliation(s)
- Roland W Herzog
- Dept. Pediatrics, University of Florida, Gainesville, FL, USA.
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48
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Plasmacytoid and conventional dendritic cells cooperate in crosspriming AAV capsid-specific CD8 + T cells. Blood 2017; 129:3184-3195. [PMID: 28468798 DOI: 10.1182/blood-2016-11-751040] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Accepted: 05/01/2017] [Indexed: 02/06/2023] Open
Abstract
Adeno-associated virus (AAV) is a replication-deficient parvovirus that is extensively used as a gene therapy vector. CD8+ T-cell responses against the AAV capsid protein can, however, affect therapeutic efficacy. Little is known about the in vivo mechanism that leads to the crosspriming of CD8+ T cells against the input viral capsid antigen. In this study, we report that the Toll-like receptor 9 (TLR9)-MyD88 pattern-recognition receptor pathway is uniquely capable of initiating this response. By contrast, the absence of TLR2, STING, or the addition of TLR4 agonist has no effect. Surprisingly, both conventional dendritic cells (cDCs) and plasmacytoid DCs (pDCs) are required for the crosspriming of capsid-specific CD8+ T cells, whereas other antigen-presenting cells are not involved. TLR9 signaling is specifically essential in pDCs but not in cDCs, indicating that sensing of the viral genome by pDCs activates cDCs in trans to cross-present capsid antigen during CD8+ T-cell activation. Cross-presentation and crosspriming depend not only on TLR9, but also on interferon type I signaling, and both mechanisms can be inhibited by administering specific molecules to prevent induction of capsid-specific CD8+ T cells. Thus, these outcomes directly point to therapeutic interventions and demonstrate that innate immune blockade can eliminate unwanted immune responses in gene therapy.
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49
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Ertl HCJ, High KA. Impact of AAV Capsid-Specific T-Cell Responses on Design and Outcome of Clinical Gene Transfer Trials with Recombinant Adeno-Associated Viral Vectors: An Evolving Controversy. Hum Gene Ther 2016; 28:328-337. [PMID: 28042943 DOI: 10.1089/hum.2016.172] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Recombinant adenovirus-associated (rAAV) vectors due to their ease of construction, wide tissue tropism, and lack of pathogenicity remain at the forefront for long-term gene replacement therapy. In spite of very encouraging preclinical results, clinical trials were initially unsuccessful; expression of the rAAV vector-delivered therapeutic protein was transient. Loss of expression was linked to an expansion of AAV capsid-specific T-cell responses, leading to the hypothesis that rAAV vectors recall pre-existing memory T cells that had been induced by natural infections with AAV together with a helper virus. Although this was hotly debated at first, AAV capsid-specific T-cell responses were observed in several gene transfer trials that used high doses of rAAV vectors. Subsequent trials designed to circumvent these T-cell responses through the use of immunosuppressive drugs, rAAV vectors based on rare serotypes, or modified to allow for therapeutic levels of the transgene product at low, non-immunogenic vector doses are now successful in correcting debilitating diseases.
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50
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Superior In vivo Transduction of Human Hepatocytes Using Engineered AAV3 Capsid. Mol Ther 2016; 24:1042-1049. [PMID: 27019999 DOI: 10.1038/mt.2016.61] [Citation(s) in RCA: 82] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 03/11/2016] [Indexed: 12/13/2022] Open
Abstract
Adeno-associated viral (AAV) vectors are currently being tested in multiple clinical trials for liver-directed gene transfer to treat the bleeding disorders hemophilia A and B and metabolic disorders. The optimal viral capsid for transduction of human hepatocytes has been under active investigation, but results across various models are inconsistent. We tested in vivo transduction in "humanized" mice. Methods to quantitate percent AAV transduced human and murine hepatocytes in chimeric livers were optimized using flow cytometry and confocal microscopy with image analysis. Distinct transduction efficiencies were noted following peripheral vein administration of a self-complementary vector expressing a gfp reporter gene. An engineered AAV3 capsid with two amino acid changes, S663V+T492V (AAV3-ST), showed best efficiency for human hepatocytes (~3-times, ~8-times, and ~80-times higher than for AAV9, AAV8, and AAV5, respectively). AAV5, 8, and 9 were more efficient in transducing murine than human hepatocytes. AAV8 yielded the highest transduction rate of murine hepatocytes, which was 19-times higher than that for human hepatocytes. In summary, our data show substantial differences among AAV serotypes in transduction of human and mouse hepatocytes, are the first to report on AAV5 in humanized mice, and support the use of AAV3-based vectors for human liver gene transfer.
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