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Viruses Feb 2021Lentiviral vectors (LVs) are potent tools for the delivery of genes of interest into mammalian cells and are now commonly utilised within the growing field of cell and... (Review)
Review
Lentiviral vectors (LVs) are potent tools for the delivery of genes of interest into mammalian cells and are now commonly utilised within the growing field of cell and gene therapy for the treatment of monogenic diseases and adoptive therapies such as chimeric antigen T-cell (CAR-T) therapy. This is a comprehensive review of the individual bioprocess operations employed in LV production. We highlight the role of envelope proteins in vector design as well as their impact on the bioprocessing of lentiviral vectors. An overview of the current state of these operations provides opportunities for bioprocess discovery and improvement with emphasis on the considerations for optimal and scalable processing of LV during development and clinical production. Upstream culture for LV generation is described with comparisons on the different transfection methods and various bioreactors for suspension and adherent producer cell cultivation. The purification of LV is examined, evaluating different sequences of downstream process operations for both small- and large-scale production requirements. For scalable operations, a key focus is the development in chromatographic purification in addition to an in-depth examination of the application of tangential flow filtration. A summary of vector quantification and characterisation assays is also presented. Finally, the assessment of the whole bioprocess for LV production is discussed to benefit from the broader understanding of potential interactions of the different process options. This review is aimed to assist in the achievement of high quality, high concentration lentiviral vectors from robust and scalable processes.
Topics: Animals; Bioreactors; Cell Culture Techniques; Cell Line; Genetic Vectors; Humans; Lentivirus; Transduction, Genetic; Viral Envelope Proteins; Virus Cultivation
PubMed: 33572347
DOI: 10.3390/v13020268 -
Signal Transduction and Targeted Therapy Feb 2021Throughout 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... (Review)
Review
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.
Topics: Dependovirus; Gene Transfer Techniques; Genetic Therapy; Genetic Vectors; Humans; Lentivirus
PubMed: 33558455
DOI: 10.1038/s41392-021-00487-6 -
International Journal of Molecular... Apr 2023Gene therapy is a technique involving the modification of an individual's genes for treating a particular disease. The key to effective gene therapy is an efficient... (Review)
Review
Gene therapy is a technique involving the modification of an individual's genes for treating a particular disease. The key to effective gene therapy is an efficient carrier delivery system. Viral vectors that have been artificially modified to lose their pathogenicity are used widely as a delivery system, with the key advantages of their natural high transduction efficiency and stable expression. With decades of development, viral vector-based gene therapies have achieved promising clinical outcomes. Currently, the three key vector strategies are based on adeno-associated viruses, adenoviruses, and lentiviruses. However, certain challenges, such as immunotoxicity and "off-target", continue to exist. In the present review, the above three viral vectors are discussed along with their respective therapeutic applications. In addition, the major translational challenges encountered in viral vector-based gene therapies are summarized, and the possible strategies to address these challenges are also discussed.
Topics: Genetic Therapy; Genetic Vectors; Lentivirus; Adenoviridae; Gene Transfer Techniques; Dependovirus
PubMed: 37175441
DOI: 10.3390/ijms24097736 -
Briefings in Functional Genomics May 2020Tools based on RNA interference (RNAi) and the recently developed clustered regularly short palindromic repeats (CRISPR) system enable the selective modification of gene...
Tools based on RNA interference (RNAi) and the recently developed clustered regularly short palindromic repeats (CRISPR) system enable the selective modification of gene expression, which also makes them attractive therapeutic reagents for combating HIV infection and other infectious diseases. Several parallels can be drawn between the RNAi and CRISPR-Cas9 platforms. An ideal RNAi or CRISPR-Cas9 therapeutic strategy for treating infectious or genetic diseases should exhibit potency, high specificity and safety. However, therapeutic applications of RNAi and CRISPR-Cas9 have been challenged by several major limitations, some of which can be overcome by optimal design of the therapy or the design of improved reagents. In this review, we will discuss some advantages and limitations of anti-HIV strategies based on RNAi and CRISPR-Cas9 with a focus on the efficiency, specificity, off-target effects and delivery methods.
Topics: Clustered Regularly Interspaced Short Palindromic Repeats; Gene Editing; Genetic Therapy; HIV Infections; Humans; Lentivirus
PubMed: 31711197
DOI: 10.1093/bfgp/elz021 -
Neuroscience Letters Aug 2019Microglia have emerged as a critical component of neurodegenerative diseases. Genetic manipulation of microglia can elucidate their functional impact in disease. In... (Review)
Review
Microglia have emerged as a critical component of neurodegenerative diseases. Genetic manipulation of microglia can elucidate their functional impact in disease. In neuroscience, recombinant viruses such as lentiviruses and adeno-associated viruses (AAVs) have been successfully used to target various cell types in the brain, although effective transduction of microglia is rare. In this review, we provide a short background of lentiviruses and AAVs, and strategies for designing recombinant viral vectors. Then, we will summarize recent literature on successful microglial transductions in vitro and in vivo, and discuss the current challenges. Finally, we provide guidelines for reporting the efficiency and specificity of viral targeting in microglia, which will enable the microglial research community to assess and improve methodologies for future studies.
Topics: Animals; Dependovirus; Gene Targeting; Genetic Vectors; HIV-1; Humans; Lentivirus; Microglia; Transduction, Genetic
PubMed: 31158432
DOI: 10.1016/j.neulet.2019.134310 -
Nature Protocols Apr 2022Human intestinal tissue-derived enteroids (HIEs; also called organoids) are a powerful ex vivo model for gastrointestinal research. Genetic modification of these... (Review)
Review
Human intestinal tissue-derived enteroids (HIEs; also called organoids) are a powerful ex vivo model for gastrointestinal research. Genetic modification of these nontransformed cultures allows new insights into gene function and biological processes involved in intestinal diseases as well as gastrointestinal and donor segment-specific function. Here we provide a detailed technical pipeline and protocol for using the CRISPR-Cas9 genome editing system to knock out a gene of interest specifically in HIEs by lentiviral transduction and single-cell cloning. This protocol differs from a previously published alternative using electroporation of human colonoids to deliver piggyback transposons or CRISPR-Cas9 constructs, as this protocol uses a modified, fused LentiCRISPRv2-small-guiding RNA to express Cas9 and small-guiding RNA in a lentivirus. The protocol also includes the steps of gene delivery and subsequent single-cell cloning of the knockout cells as well as verification of clones and sequence identification of the mutation sites to establish knockout clones. An overview flowchart, step-by-step guidelines and troubleshooting suggestions are provided to aid the researcher in obtaining the genetic knockout HIE line within 2-3 months. In this protocol, we further describe how to use HIEs as an ex vivo model to assess host restriction factors for viral replication (using human norovirus replication as an example) by knocking out host attachment factors or innate immunity genes. Other applications are discussed to broaden the utility of this system, for example, to generate knockin or conditional knockout HIE lines to investigate the function of essential genes in many biological processes including other types of organoids.
Topics: CRISPR-Cas Systems; Clone Cells; Cloning, Molecular; Gene Editing; Gene Knockout Techniques; Humans; Lentivirus; RNA, Guide, CRISPR-Cas Systems
PubMed: 35197604
DOI: 10.1038/s41596-021-00669-0 -
Cell May 2023Entry of enveloped viruses into cells is mediated by viral fusogenic proteins that drive membrane rearrangements needed for fusion between viral and target membranes....
Entry of enveloped viruses into cells is mediated by viral fusogenic proteins that drive membrane rearrangements needed for fusion between viral and target membranes. Skeletal muscle development also requires membrane fusion events between progenitor cells to form multinucleated myofibers. Myomaker and Myomerger are muscle-specific cell fusogens but do not structurally or functionally resemble classical viral fusogens. We asked whether the muscle fusogens could functionally substitute for viral fusogens, despite their structural distinctiveness, and fuse viruses to cells. We report that engineering of Myomaker and Myomerger on the membrane of enveloped viruses leads to specific transduction of skeletal muscle. We also demonstrate that locally and systemically injected virions pseudotyped with the muscle fusogens can deliver μDystrophin to skeletal muscle of a mouse model of Duchenne muscular dystrophy and alleviate pathology. Through harnessing the intrinsic properties of myogenic membranes, we establish a platform for delivery of therapeutic material to skeletal muscle.
Topics: Animals; Mice; Cell Fusion; Membrane Fusion; Membrane Proteins; Muscle Development; Muscle, Skeletal; Bioengineering; Muscular Dystrophy, Duchenne; Disease Models, Animal; Viral Tropism; Lentivirus
PubMed: 37075755
DOI: 10.1016/j.cell.2023.03.033 -
Viruses Aug 2021Lentiviral vectors have played a critical role in the emergence of gene-modified cell therapies, specifically T cell therapies. Tisagenlecleucel (Kymriah), axicabtagene... (Review)
Review
Lentiviral vectors have played a critical role in the emergence of gene-modified cell therapies, specifically T cell therapies. Tisagenlecleucel (Kymriah), axicabtagene ciloleucel (Yescarta) and most recently brexucabtagene autoleucel (Tecartus) are examples of T cell therapies which are now commercially available for distribution after successfully obtaining EMA and FDA approval for the treatment of blood cancers. All three therapies rely on retroviral vectors to transduce the therapeutic chimeric antigen receptor (CAR) into T lymphocytes. Although these innovations represent promising new therapeutic avenues, major obstacles remain in making them readily available tools for medical care. This article reviews the biological principles as well as the bioprocessing of lentiviral (LV) vectors and adoptive T cell therapy. Clinical and engineering successes, shortcomings and future opportunities are also discussed. The development of Good Manufacturing Practice (GMP)-compliant instruments, technologies and protocols will play an essential role in the development of LV-engineered T cell therapies.
Topics: Cell Engineering; Clinical Trials as Topic; Genetic Vectors; Humans; Immunotherapy, Adoptive; Lentivirus; Neoplasms; Receptors, Chimeric Antigen; T-Lymphocytes
PubMed: 34452392
DOI: 10.3390/v13081528 -
The New England Journal of Medicine May 2021Severe combined immunodeficiency due to adenosine deaminase (ADA) deficiency (ADA-SCID) is a rare and life-threatening primary immunodeficiency.
BACKGROUND
Severe combined immunodeficiency due to adenosine deaminase (ADA) deficiency (ADA-SCID) is a rare and life-threatening primary immunodeficiency.
METHODS
We treated 50 patients with ADA-SCID (30 in the United States and 20 in the United Kingdom) with an investigational gene therapy composed of autologous CD34+ hematopoietic stem and progenitor cells (HSPCs) transduced ex vivo with a self-inactivating lentiviral vector encoding human . Data from the two U.S. studies (in which fresh and cryopreserved formulations were used) at 24 months of follow-up were analyzed alongside data from the U.K. study (in which a fresh formulation was used) at 36 months of follow-up.
RESULTS
Overall survival was 100% in all studies up to 24 and 36 months. Event-free survival (in the absence of reinitiation of enzyme-replacement therapy or rescue allogeneic hematopoietic stem-cell transplantation) was 97% (U.S. studies) and 100% (U.K. study) at 12 months; 97% and 95%, respectively, at 24 months; and 95% (U.K. study) at 36 months. Engraftment of genetically modified HSPCs persisted in 29 of 30 patients in the U.S. studies and in 19 of 20 patients in the U.K. study. Patients had sustained metabolic detoxification and normalization of ADA activity levels. Immune reconstitution was robust, with 90% of the patients in the U.S. studies and 100% of those in the U.K. study discontinuing immunoglobulin-replacement therapy by 24 months and 36 months, respectively. No evidence of monoclonal expansion, leukoproliferative complications, or emergence of replication-competent lentivirus was noted, and no events of autoimmunity or graft-versus-host disease occurred. Most adverse events were of low grade.
CONCLUSIONS
Treatment of ADA-SCID with ex vivo lentiviral HSPC gene therapy resulted in high overall and event-free survival with sustained expression, metabolic correction, and functional immune reconstitution. (Funded by the National Institutes of Health and others; ClinicalTrials.gov numbers, NCT01852071, NCT02999984, and NCT01380990.).
Topics: Adenosine Deaminase; Adolescent; Agammaglobulinemia; Child; Child, Preschool; Genetic Therapy; Genetic Vectors; Hematopoietic Stem Cell Transplantation; Humans; Infant; Lentivirus; Lymphocyte Count; Progression-Free Survival; Prospective Studies; Severe Combined Immunodeficiency; Transplantation, Autologous
PubMed: 33974366
DOI: 10.1056/NEJMoa2027675 -
Nature Methods Apr 2022Deciphering immune recognition is critical for understanding a broad range of diseases and for the development of effective vaccines and immunotherapies. Efforts to do...
Deciphering immune recognition is critical for understanding a broad range of diseases and for the development of effective vaccines and immunotherapies. Efforts to do so are limited by a lack of technologies capable of simultaneously capturing the complexity of adaptive immunoreceptor repertoires and the landscape of potential antigens. To address this, we present receptor-antigen pairing by targeted retroviruses, which combines viral pseudotyping and molecular engineering approaches to enable one-pot library-on-library interaction screens by displaying antigens on the surface of lentiviruses and encoding their identity in the viral genome. Antigen-specific viral infection of cell lines expressing human T or B cell receptors allows readout of both antigen and receptor identities via single-cell sequencing. The resulting system is modular, scalable and compatible with any cell type. These techniques provide a suite of tools for targeted viral entry, molecular engineering and interaction screens with broad potential applications.
Topics: Antigens; Antigens, Viral; Humans; Immunotherapy; Lentivirus; Receptors, Antigen, B-Cell; Receptors, Antigen, T-Cell; Virus Internalization
PubMed: 35396484
DOI: 10.1038/s41592-022-01436-z