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Aso M, Yamamoto TT, Kuroda M, Wada J, Kubota Y, Ishikawa K, Maezawa Y, Teramoto N, Tawada A, Asada S, Aoyagi Y, Kirinashizawa M, Onitake A, Matsuura Y, Yasunaga K, Konno SI, Nishino K, Yamamoto M, Miyoshi J, Kobayashi N, Tanio M, Ikeuchi T, Igari H, Mitsukawa N, Hanaoka H, Yokote K, Saito Y. First-in-human autologous implantation of genetically modified adipocytes expressing LCAT for the treatment of familial LCAT deficiency. Heliyon 2022; 8:e11271. [PMID: 36387451 PMCID: PMC9663876 DOI: 10.1016/j.heliyon.2022.e11271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 02/21/2022] [Accepted: 10/20/2022] [Indexed: 11/13/2022] Open
Abstract
Background Familial lecithin: cholesterol acyltransferase (LCAT) deficiency (FLD) is a severe inherited disease without effective treatment. Patients with FLD develop severe low HDL, corneal opacity, hemolytic anemia, and renal injury. Objective We developed genetically modified adipocytes (GMAC) secreting LCAT (LCAT-GMAC) for ex vivo gene therapy. GMACs were prepared from the patient’s adipocytes to express LCAT by retroviral gene transduction to secrete functional enzymes. This study aimed to evaluate the safety and efficacy of LCAT-GMAC implantation in an FLD patient. Methods Proliferative preadipocytes were obtained from a patient using a ceiling culture and retrovirally transduced with LCAT. After obtaining enough cells by expansion culture of the transduced cells, the resulting LCAT-GMACs were implanted into a patient with FLD. To evaluate the safety and efficacy, we analyzed the outcome of the autologous implantation for 24 weeks of observation and subsequent 240 weeks of the follow-up periods. Results This first-in-human autologous implantation of LCAT-GMACs was shown to be safe by evaluating adverse events. The LCAT-GMAC implantation increased serum LCAT activity by approximately 50% of the baseline and sustained over three years. Consistent with increased LCAT activity, intermediate-density lipoprotein (IDL) and free cholesterol levels of the small and very small HDL fractions decreased. We found the hemoglobin/haptoglobin complex in the hemolyzed pre-implantation sera of the patient. After one week of the implantation, the hemoglobin/haptoglobin complex almost disappeared. Immediately after the implantation, the patient's proteinuria decreased temporarily to mild levels and gradually increased to the baseline. At 48 weeks after implantation, the patient's proteinuria deteriorated with the development of mild hypertension. By the treatment with antihypertensives, the patient's blood pressure normalized. With the normalization of blood pressure, the proteinuria rapidly decreased to mild proteinuria levels. Conclusions LCAT-GMAC implantation in a patient with FLD is shown to be safe and appears to be effective, in part, for treating anemia and proteinuria in FLD.
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Affiliation(s)
| | | | - Masayuki Kuroda
- Center for Advanced Medicine, Chiba University Hospital, 2608677 Chiba, Japan
| | - Jun Wada
- Department of Nephrology, Rheumatology, Endocrinology and Metabolism, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 7008530 Okayama, Japan
| | - Yoshitaka Kubota
- Department of Plastic and Reconstructive Surgery, Chiba University, Faculty of Medicine, 2608670 Chiba, Japan
| | - Ko Ishikawa
- Department of Endocrinology, Hematology, and Gerontology, Chiba University, Graduates School of Medicine and Department of Diabetes, Metabolism, and Endocrinology, Chiba University Hospital, 2608670 Chiba, Japan
| | - Yoshiro Maezawa
- Department of Endocrinology, Hematology, and Gerontology, Chiba University, Graduates School of Medicine and Department of Diabetes, Metabolism, and Endocrinology, Chiba University Hospital, 2608670 Chiba, Japan
| | - Naoya Teramoto
- Department of Endocrinology, Hematology, and Gerontology, Chiba University, Graduates School of Medicine and Department of Diabetes, Metabolism, and Endocrinology, Chiba University Hospital, 2608670 Chiba, Japan
| | - Ayako Tawada
- Department of Ophthalmology and Visual Science, Chiba University Graduate School of Medicine, 2608670 Chiba, Japan
| | | | | | | | | | | | | | | | | | | | | | | | | | - Takayuki Ikeuchi
- Chiba University Hospital Clinical Research Center, 2608677 Chiba, Japan
| | - Hidetoshi Igari
- Division of Infection Control, Chiba University Hospital, 2608677 Chiba, Japan
| | - Nobuyuki Mitsukawa
- Department of Plastic and Reconstructive Surgery, Chiba University, Faculty of Medicine, 2608670 Chiba, Japan
| | - Hideki Hanaoka
- Chiba University Hospital Clinical Research Center, 2608677 Chiba, Japan
| | - Koutaro Yokote
- Department of Endocrinology, Hematology, and Gerontology, Chiba University, Graduates School of Medicine and Department of Diabetes, Metabolism, and Endocrinology, Chiba University Hospital, 2608670 Chiba, Japan
- Corresponding author.
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Toon K, Bentley EM, Mattiuzzo G. More Than Just Gene Therapy Vectors: Lentiviral Vector Pseudotypes for Serological Investigation. Viruses 2021; 13:217. [PMID: 33572589 PMCID: PMC7911487 DOI: 10.3390/v13020217] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 01/22/2021] [Accepted: 01/26/2021] [Indexed: 12/13/2022] Open
Abstract
Serological assays detecting neutralising antibodies are important for determining the immune responses following infection or vaccination and are also often considered a correlate of protection. The target of neutralising antibodies is usually located in the Envelope protein on the viral surface, which mediates cell entry. As such, presentation of the Envelope protein on a lentiviral particle represents a convenient alternative to handling of a potentially high containment virus or for those viruses with no established cell culture system. The flexibility, relative safety and, in most cases, ease of production of lentiviral pseudotypes, have led to their use in serological assays for many applications such as the evaluation of candidate vaccines, screening and characterization of anti-viral therapeutics, and sero-surveillance. Above all, the speed of production of the lentiviral pseudotypes, once the envelope sequence is published, makes them important tools in the response to viral outbreaks, as shown during the COVID-19 pandemic in 2020. In this review, we provide an overview of the landscape of the serological applications of pseudotyped lentiviral vectors, with a brief discussion on their production and batch quality analysis. Finally, we evaluate their role as surrogates for the real virus and possible alternatives.
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Affiliation(s)
- Kamilla Toon
- Division of Virology, National Institute for Biological Standards and Control-MHRA, Blanche Lane, South Mimms EN6 3QG, UK;
- Division of Infection and Immunity, University College London, London WC1E 6BT, UK
| | - Emma M. Bentley
- Division of Virology, National Institute for Biological Standards and Control-MHRA, Blanche Lane, South Mimms EN6 3QG, UK;
| | - Giada Mattiuzzo
- Division of Virology, National Institute for Biological Standards and Control-MHRA, Blanche Lane, South Mimms EN6 3QG, UK;
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Soni S, Kohn DB. Chemistry, manufacturing and controls for gene modified hematopoietic stem cells. Cytotherapy 2019; 21:358-366. [PMID: 30745225 DOI: 10.1016/j.jcyt.2018.12.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Revised: 12/05/2018] [Accepted: 12/06/2018] [Indexed: 12/17/2022]
Abstract
Gene modification of hematopoietic stem cells is increasingly becoming popular as a therapeutic approach, given the recent approvals and the number of new applications for clinical trials targeting monogenetic and immunodeficiency disorders. Technological advances in stem cell selection, culture, transduction and gene editing now allow for efficient ex vivo genetic manipulation of stem cells. Gene-addition techniques using viral vectors (mainly retrovirus- and lentivirus-based) and gene editing using various targeted nuclease platforms (e.g., Zinc finger, TALEN and Crispr/Cas9) are being applied to the treatment of multiple genetic and immunodeficiency disorders. Herein, the current state of the art in manufacturing and critical assays that are required for ex vivo manipulation of stem cells are addressed. Important quality control and safety assays that need to be planned early in the process development phase of these products for regulatory approval are also highlighted.
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Affiliation(s)
- Sandeep Soni
- Division of Stem Cell Transplant and Regenerative Medicine, Lucile Packard Children's Hospital, Stanford University, Palo Alto, California, USA.
| | - Donald B Kohn
- Department of Microbiology, Immunology and Molecular Genetics, University of California Los Angeles, Los Angeles, California, USA
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Retroviral and Lentiviral Safety Analysis of Gene-Modified T Cell Products and Infused HIV and Oncology Patients. Mol Ther 2017; 26:269-279. [PMID: 29203150 DOI: 10.1016/j.ymthe.2017.10.012] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Revised: 10/16/2017] [Accepted: 10/17/2017] [Indexed: 01/14/2023] Open
Abstract
Replication-competent retrovirus/lentivirus (RCR/L) and insertional oncogenesis are potential safety risks with integrating viruses in gene-modified cell therapies. As such, the Food and Drug Administration guidances outline RCR/L-monitoring methods throughout the entire gene therapy treatment cycle. We present data for 17 vector lots, 375 manufactured T cell products, and 308 patients post-infusion across both HIV and oncology indications, showing no evidence of RCR/L. Given our data, a Poisson probability model estimates that a single patient, or a group of patients, would need to be followed for at least 52.8 years to observe one positive RCR/L event, highlighting the unlikelihood of RCR/L development. Additionally, we estimate the median time for lentivirus-modified T cell products to fall below the 1% vector sequence threshold in peripheral or whole blood that would trigger vector integration site analysis. These estimated times are 1.4 months in hematologic malignancies, 0.66 month in solid tumors, and 0.92 month in HIV. Based on these considerable safety data in HIV and oncology and recent Biologics License Applications filed for lentiviral-modified T cell products for hematologic malignancies, this may be an opportune time to re-evaluate the current guidelines for T cell gene therapy product testing and long-term patient monitoring.
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Negri D, Blasi M, LaBranche C, Parks R, Balachandran H, Lifton M, Shen X, Denny T, Ferrari G, Vescio MF, Andersen H, Montefiori DC, Tomaras GD, Liao HX, Santra S, Haynes BF, Klotman ME, Cara A. Immunization with an SIV-based IDLV Expressing HIV-1 Env 1086 Clade C Elicits Durable Humoral and Cellular Responses in Rhesus Macaques. Mol Ther 2016; 24:2021-2032. [PMID: 27455880 PMCID: PMC5154473 DOI: 10.1038/mt.2016.123] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 06/11/2016] [Indexed: 02/05/2023] Open
Abstract
The design of an effective HIV-1 vaccine remains a major challenge. Several vaccine strategies based on viral vectors have been evaluated in preclinical and clinical trials, with largely disappointing results. Integrase defective lentiviral vectors (IDLV) represent a promising vaccine candidate given their ability to induce durable and protective immune responses in mice after a single immunization. Here, we evaluated the immunogenicity of a SIV-based IDLV in nonhuman primates. Six rhesus monkeys were primed intramuscularly with IDLV-Env and boosted with the same vector after 1 year. A single immunization with IDLV-Env induced broad humoral and cellular immune responses that waned over time but were still detectable at 1 year postprime. The boost with IDLV-Env performed at 1 year from the prime induced a remarkable increase in both antibodies and T-cell responses. Antibody binding specificity showed a predominant cross-clade gp120-directed response. Monkeys' sera efficiently blocked anti-V2 and anti-CD4 binding site antibodies, neutralized the tier 1 MW965.26 pseudovirus and mediated antibody-dependent cellular cytotoxicity (ADCC). Durable polyfunctional Env-specific T-cell responses were also elicited. Our study demonstrates that an IDLV-Env-based vaccine induces functional, comprehensive, and durable immune responses in Rhesus macaques. These results support further evaluation of IDLV as a new HIV-1 vaccine delivery platform.
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Affiliation(s)
- Donatella Negri
- Department of Medicine, Duke University Medical Center, Durham, North Carolina, USA; Department of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy
| | - Maria Blasi
- Department of Medicine, Duke University Medical Center, Durham, North Carolina, USA
| | - Celia LaBranche
- Department of Surgery, Duke University Medical Center, Durham, North Carolina, USA
| | - Robert Parks
- Department of Medicine, Duke University Medical Center, Durham, North Carolina, USA; Duke Human Vaccine Institute, Duke University Medical Center, Durham, North Carolina, USA
| | | | - Michelle Lifton
- Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA
| | - Xiaoying Shen
- Department of Medicine, Duke University Medical Center, Durham, North Carolina, USA; Duke Human Vaccine Institute, Duke University Medical Center, Durham, North Carolina, USA
| | - Thomas Denny
- Department of Medicine, Duke University Medical Center, Durham, North Carolina, USA; Duke Human Vaccine Institute, Duke University Medical Center, Durham, North Carolina, USA
| | - Guido Ferrari
- Department of Surgery, Duke University Medical Center, Durham, North Carolina, USA
| | | | | | - David C Montefiori
- Department of Surgery, Duke University Medical Center, Durham, North Carolina, USA
| | - Georgia D Tomaras
- Department of Surgery, Duke University Medical Center, Durham, North Carolina, USA; Duke Human Vaccine Institute, Duke University Medical Center, Durham, North Carolina, USA
| | - Hua-Xin Liao
- Department of Medicine, Duke University Medical Center, Durham, North Carolina, USA; Duke Human Vaccine Institute, Duke University Medical Center, Durham, North Carolina, USA
| | - Sampa Santra
- Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA
| | - Barton F Haynes
- Department of Medicine, Duke University Medical Center, Durham, North Carolina, USA; Duke Human Vaccine Institute, Duke University Medical Center, Durham, North Carolina, USA
| | - Mary E Klotman
- Department of Medicine, Duke University Medical Center, Durham, North Carolina, USA.
| | - Andrea Cara
- Department of Medicine, Duke University Medical Center, Durham, North Carolina, USA; Department of Therapeutic Research and Medicines Evaluation, Istituto Superiore di Sanità, Rome, Italy.
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Hu Y, O'Boyle K, Palmer D, Ng P, Sutton RE. High-level production of replication-defective human immunodeficiency type 1 virus vector particles using helper-dependent adenovirus vectors. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2015; 2:15004. [PMID: 26029715 PMCID: PMC4444993 DOI: 10.1038/mtm.2015.4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Revised: 01/08/2015] [Accepted: 01/09/2015] [Indexed: 11/09/2022]
Abstract
Gene transfer vectors based upon human immunodeficiency virus type 1 (HIV) are widely used in bench research applications and increasingly in clinical investigations, both to introduce novel genes but also to reduce expression of unwanted genes of the host and pathogen. At present, the vast majority of HIV-based vector supernatants are produced in 293T cells by cotransfection of up to five DNA plasmids, which is subject to variability and difficult to scale. Here we report the development of a HIV-based vector production system that utilizes helper-dependent adenovirus (HDAd). All necessary HIV vector components were inserted into one or more HDAds, which were then amplified to very high titers of ~1013 vp/ml. These were then used to transduce 293-based cells to produce HIV-based vector supernatants, and resultant VSV G-pseudotyped lentiviral vector (LV) titers and total IU were 10- to 30-fold higher, compared to plasmid transfection. Optimization of HIV-based vector production depended upon maximizing expression of all HIV vector components from HDAd. Supernatants contained trace amounts of HDAd but were free of replication-competent lentivirus. This production method should be applicable to other retroviral vector systems. Scalable production of HIV-based vectors using this two-step procedure should facilitate their clinical advancement.
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Affiliation(s)
- Yani Hu
- Division of Infectious Diseases, Department of Internal Medicine, Yale University School of Medicine , New Haven, Connecticut, USA
| | - Kaitlin O'Boyle
- Division of Infectious Diseases, Department of Internal Medicine, Yale University School of Medicine , New Haven, Connecticut, USA
| | - Donna Palmer
- Department of Molecular and Human Genetics, Baylor College of Medicine , Houston, Texas, USA
| | - Philip Ng
- Department of Molecular and Human Genetics, Baylor College of Medicine , Houston, Texas, USA
| | - Richard E Sutton
- Division of Infectious Diseases, Department of Internal Medicine, Yale University School of Medicine , New Haven, Connecticut, USA
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Manufacturing of viral vectors: part II. Downstream processing and safety aspects. ACTA ACUST UNITED AC 2014. [DOI: 10.4155/pbp.14.15] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Kuate S, Marino MP, Reiser J. Analysis of partial recombinants in lentiviral vector preparations. Hum Gene Ther Methods 2014; 25:126-35. [PMID: 24367910 DOI: 10.1089/hgtb.2013.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The presence of replication-competent lentivirus (RCL) in lentiviral vector preparations is a major safety concern for clinical applications of such vectors. RCL are believed to emerge from rare recombinant vector genomes that are referred to as partial recombinants or Psi-Gag recombinants. To quantitatively determine the fraction of partial recombinants in lentiviral vector preparations and to analyze them at the DNA sequence level, we established a drug selection assay involving a lentiviral packaging construct containing a drug-resistance gene encoding blasticidin (BSD) resistance. Upon transduction of target cells, the BSD resistance gene confers BSD resistance to the transduced cells. The results obtained indicate that there were up to 156 BSD-resistant colonies in a total of 10(6) transducing vector particles. The predicted recombination events were verified by polymerase chain reaction using genomic DNA obtained from BSD-resistant cell clones and by DNA sequence analysis. In an attempt to reduce the emergence of partial recombinants, sequence overlaps between the packaging and the vector constructs were reduced by substituting the Rev response element (RRE) present in the vector construct using a heterologous RRE element derived from simian immunodeficiency virus (SIVmac239). The results obtained showed that a reduction of sequence overlaps resulted in an up to sevenfold reduction of the frequency of BSD-resistant colonies, indicating that the capacity to form partial recombinants was diminished.
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Affiliation(s)
- Seraphin Kuate
- Division of Cellular and Gene Therapies, Center for Biologics Evaluation and Research , U.S. Food and Drug Administration, Bethesda, MD 20892
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Tareen SU, Nicolai CJ, Campbell DJ, Flynn PA, Slough MM, Vin CD, Kelley-Clarke B, Odegard JM, Robbins SH. A Rev-Independent gag/pol Eliminates Detectable psi-gag Recombination in Lentiviral Vectors. Biores Open Access 2013; 2:421-30. [PMID: 24380052 PMCID: PMC3869434 DOI: 10.1089/biores.2013.0037] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Lentiviral vectors (LVs) are being developed for clinical use in humans for applications including gene therapy and immunotherapy. A safety concern for use of LVs in humans is the generation of replication-competent lentivirus (RCL), which may arise due to recombination between the split genomes of third-generation LVs. Although no RCL has been detected to date, design optimizations that minimize recombination events between split genome vectors would provide an added safety benefit that may further reduce the risk of RCL formation. Here we describe design elements introduced to the gag/pol plasmid with the intention of eliminating psi-gag recombination between the vector genome and gag/pol. These design changes, consisting of codon optimization of the gag/pol sequence and the deletion of the Rev-responsive element, abrogate the requirement for Rev in expression of Gag protein, thus the resulting gag/pol construct being Rev independent (RI gag/pol). We show that generating vector using the RI gag/pol construct has no effect on particle production or transduction titers. The RI and wild-type gag/pol vectors function equivalently as antigen-specific immunotherapy, potently inducing antigen-specific CD8 T cells that protect against challenge with vaccinia virus. Most importantly, the designed RI gag/pol eliminated detectable psi-gag recombination. Interestingly, we detected recombination between the vector genome and gag/pol from regions without sequence homology. Our findings imply that although unpredictable recombination events may still occur, the RI gag/pol design is sufficient to prevent psi-gag recombination.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Scott H Robbins
- Immune Design Corporation , Seattle, Washington. ; TRIA Bioscience Corporation , Seattle, Washington
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Farley DC, Bannister R, Leroux-Carlucci MA, Evans NE, Miskin JE, Mitrophanous KA. Development of an equine-tropic replication-competent lentivirus assay for equine infectious anemia virus-based lentiviral vectors. Hum Gene Ther Methods 2012; 23:309-23. [PMID: 23121195 DOI: 10.1089/hgtb.2012.102] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The release of lentiviral vectors for clinical use requires the testing of vector material, production cells, and, if applicable, ex vivo-transduced cells for the presence of replication-competent lentivirus (RCL). Vectors derived from the nonprimate lentivirus equine infectious anemia virus (EIAV) have been directly administered to patients in several clinical trials, with no toxicity observed to date. Because EIAV does not replicate in human cells, and because putative RCLs derived from vector components within human vector production cells would most likely be human cell-tropic, we previously developed an RCL assay using amphotropic murine leukemia virus (MLV) as a surrogate positive control and human cells as RCL amplification/indicator cells. Here we report an additional RCL assay that tests for the presence of theoretical "equine-tropic" RCLs. This approach provides further assurance of safety by detecting putative RCLs with an equine cell-specific tropism that might not be efficiently amplified by the human cell-based RCL assay. We tested the ability of accessory gene-deficient EIAV mutant viruses to replicate in a highly permissive equine cell line to direct our choice of a suitable EIAV-derived positive control. In addition, we report for the first time the mathematical rationale for use of the Poisson distribution to calculate minimal infectious dose of positive control virus and for use in monitoring assay positive/spike control failures in accumulating data sets. No RCLs have been detected in Good Manufacturing Practice (GMP)-compliant RCL assays to date, further demonstrating that RCL formation is highly unlikely in contemporary minimal lentiviral vector systems.
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Abstract
While novel retroviral vectors for use in gene-therapy products are reducing the potential for formation of replication-competent retrovirus (RCR), it remains crucial to screen products for RCR for both research and clinical purposes. For clinical grade gammaretrovirus-based vectors, RCR screening is achieved by an extended S+L− or marker rescue assay, while standard methods for replication-competent lentivirus detection are still in development. In this report, we describe a rapid and sensitive method for replication-competent gammaretrovirus detection. We used this assay to detect three members of the gammaretrovirus family and compared the sensitivity of our assay with well-established methods for retrovirus detection, including the extended S+L− assay. Results presented here demonstrate that this assay should be useful for gene-therapy product testing.
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