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Improved Manufacturing Methods of Extracellular Vesicles Pseudotyped with the Vesicular Stomatitis Virus Glycoprotein. Mol Biotechnol 2024; 66:1116-1131. [PMID: 38182864 DOI: 10.1007/s12033-023-01007-3] [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: 07/12/2023] [Accepted: 11/27/2023] [Indexed: 01/07/2024]
Abstract
Extracellular vesicles (EV), which expose the vesicular stomatitis virus glycoprotein (VSVG) on their surface, are used for delivery of nucleic acids and proteins in human cell lines. These particles are biomanufactured using methods that are difficult to scale up. Here, we describe the development of the first EV-VSVG production process in serum-free media using polyethylenimine (PEI)-based transient transfection of HEK293 suspension cells, as well as the first EV-VSVG purification process to utilize both ultracentrifugation and chromatography. Three parameters were investigated for EV-VSVG production: cell density, DNA concentration, and DNA:PEI ratio. The best production titer was obtained with 3 × 106 cells/mL, a plasmid concentration of 2 µg/mL, and a DNA:PEI ratio of 1:4. The production kinetics of VSVG was performed and showed that the highest amount of VSVG was obtained 3 days after transfection. Addition of cell culture supplements during the transfection resulted in an increase in VSVG production, with a maximum yield obtained with 2 mM of sodium butyrate added 18 h after transfection. Moreover, the absence of EV-VSVG during cell transfection with a GFP-coding plasmid revealed to be ineffective, with no fluorescent cells. An efficient EV-VSVG purification procedure consisting of a two-step concentration by low-speed centrifugation and sucrose cushion ultracentrifugation followed by a heparin affinity chromatography purification was also developed. Purified bioactive EV-VSVG preparations were characterized and revealed that EV-VSVG are spherical particles of 176.4 ± 88.32 nm with 91.4% of protein similarity to exosomes.
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Impact of Recombinant VSV-HIV Prime, DNA-Boost Vaccine Candidates on Immunogenicity and Viremia on SHIV-Infected Rhesus Macaques. Vaccines (Basel) 2024; 12:369. [PMID: 38675751 PMCID: PMC11053682 DOI: 10.3390/vaccines12040369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Revised: 03/25/2024] [Accepted: 03/26/2024] [Indexed: 04/28/2024] Open
Abstract
Currently, no effective vaccine to prevent human immunodeficiency virus (HIV) infection is available, and various platforms are being examined. The vesicular stomatitis virus (VSV) vaccine vehicle can induce robust humoral and cell-mediated immune responses, making it a suitable candidate for the development of an HIV vaccine. Here, we analyze the protective immunological impacts of recombinant VSV vaccine vectors that express chimeric HIV Envelope proteins (Env) in rhesus macaques. To improve the immunogenicity of these VSV-HIV Env vaccine candidates, we generated chimeric Envs containing the transmembrane and cytoplasmic tail of the simian immunodeficiency virus (SIV), which increases surface Env on the particle. Additionally, the Ebola virus glycoprotein was added to the VSV-HIV vaccine particles to divert tropism from CD4 T cells and enhance their replications both in vitro and in vivo. Animals were boosted with DNA constructs that encoded matching antigens. Vaccinated animals developed non-neutralizing antibody responses against both the HIV Env and the Ebola virus glycoprotein (EBOV GP) as well as systemic memory T-cell activation. However, these responses were not associated with observable protection against simian-HIV (SHIV) infection following repeated high-dose intra-rectal SHIV SF162p3 challenges.
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Discovery and preclinical development of a therapeutically active nanobody-based chimeric antigen receptor targeting human CD22. MOLECULAR THERAPY. ONCOLOGY 2024; 32:200775. [PMID: 38596311 PMCID: PMC10914482 DOI: 10.1016/j.omton.2024.200775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 01/22/2024] [Accepted: 02/09/2024] [Indexed: 04/11/2024]
Abstract
Chimeric antigen receptor (CAR) T cell therapies targeting B cell-restricted antigens CD19, CD20, or CD22 can produce potent clinical responses for some B cell malignancies, but relapse remains common. Camelid single-domain antibodies (sdAbs or nanobodies) are smaller, simpler, and easier to recombine than single-chain variable fragments (scFvs) used in most CARs, but fewer sdAb-CARs have been reported. Thus, we sought to identify a therapeutically active sdAb-CAR targeting human CD22. Immunization of an adult Llama glama with CD22 protein, sdAb-cDNA library construction, and phage panning yielded >20 sdAbs with diverse epitope and binding properties. Expressing CD22-sdAb-CAR in Jurkat cells drove varying CD22-specific reactivity not correlated with antibody affinity. Changing CD28- to CD8-transmembrane design increased CAR persistence and expression in vitro. CD22-sdAb-CAR candidates showed similar CD22-dependent CAR-T expansion in vitro, although only membrane-proximal epitope targeting CD22-sdAb-CARs activated direct cytolytic killing and extended survival in a lymphoma xenograft model. Based on enhanced survival in blinded xenograft studies, a lead CD22sdCAR-T was selected, achieving comparable complete responses to a benchmark short linker m971-scFv CAR-T in high-dose experiments. Finally, immunohistochemistry and flow cytometry confirm tissue and cellular-level specificity of the lead CD22-sdAb. This presents a complete report on preclinical development of a novel CD22sdCAR therapeutic.
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Production, purification and immunogenicity of Gag virus-like particles carrying SARS-CoV-2 components. Vaccine 2024; 42:40-52. [PMID: 38042697 DOI: 10.1016/j.vaccine.2023.11.048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 10/28/2023] [Accepted: 11/23/2023] [Indexed: 12/04/2023]
Abstract
The virus-like particle (VLP) platform is a robust inducer of humoral and cellular immune responses; hence, it has been used in vaccine development for several infectious diseases. In the current work, VLPs carrying SARS-CoV-2 Spike (S) protein (Wuhan strain) with an HIV-1 Gag core were produced using suspension HEK 293SF-3F6 cells by transient transfection. The Gag was fused with green fluorescent protein (GFP) for rapid quantification of the VLPs. Five different versions of Gag-Spike VLPs (Gag-S-VLPs) consisting of Gag-S alone or combined with other SARS-CoV-2 components, namely Gag-S-Nucleocapsid (N), Gag-S-Matrix (M), Gag-S-Envelope (E), Gag-S-MEN, along with Gag alone were produced and processed by clarification, nuclease treatment, concentration by tangential flow filtration (TFF) and diafiltration. A pilot mouse study was performed to evaluate the immunogenicity of the Gag-S-VLPs through the measurement of the humoral and/or cellular responses against all the mentioned SARS-CoV-2 components. Antibody response to Spike was observed in all variants. The highest number of Spike-specific IFN-γ + T cells was detected with Gag-S-VLPs. No induction of antigen-specific cellular responses to M, N or E proteins were detected with any of the Gag-S, M, E/or N VLPs tested. Therefore, the Gag-S-VLP, by reason of consistently eliciting strong antigen-specific cellular and antibody responses, was selected for further evaluation. The purification process was improved by replacing the conventional centrifugation by serial microfiltration in the clarification step, followed by Spike-affinity chromatography to get concentrated VLPs with higher purity. Three different doses of Gag-S-VLP in conjunction with two adjuvants (Quil-A or AddaVax) were used to assess the dose-dependent antigen-specific cellular and antibody responses in mice. The Gag-S-VLP adjuvanted with Quil-A resulted in a stronger Spike-specific cellular response compared to that adjuvanted with AddaVax. A strong spike neutralisation activity was observed for all doses, independent of the adjuvant combination.
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Development, optimization, and scale-up of suspension Vero cell culture process for high titer production of oncolytic herpes simplex virus-1. Biotechnol J 2024; 19:e2300244. [PMID: 37767876 DOI: 10.1002/biot.202300244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 07/20/2023] [Accepted: 09/26/2023] [Indexed: 09/29/2023]
Abstract
Oncolytic viruses (OVs) have emerged as a novel cancer treatment modality, and four OVs have been approved for cancer immunotherapy. However, high-yield and cost-effective production processes remain to be developed for most OVs. Here suspension-adapted Vero cell culture processes were developed for high titer production of an OV model, herpes simplex virus type 1 (HSV-1). Our study showed the HSV-1 productivity was significantly affected by multiplicity of infection, cell density, and nutritional supplies. Cell culture conditions were first optimized in shake flask experiments and then scaled up to 3 L bioreactors for virus production under batch and perfusion modes. A titer of 2.7 × 108 TCID50 mL-1 was obtained in 3 L batch culture infected at a cell density of 1.4 × 106 cells mL-1 , and was further improved to 1.1 × 109 TCID50 mL-1 in perfusion culture infected at 4.6 × 106 cells mL-1 . These titers are similar to or better than the previously reported best titer of 8.6 × 107 TCID50 mL-1 and 8.1 × 108 TCID50 mL-1 respectively obtained in labor-intensive adherent Vero batch and perfusion cultures. HSV-1 production in batch culture was successfully scaled up to 60 L pilot-scale bioreactor to demonstrate the scalability. The work reported here is the first study demonstrating high titer production of HSV-1 in suspension Vero cell culture under different bioreactor operating modes.
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A Method to Generate and Rescue Recombinant Adenovirus Devoid of Replication-Competent Particles in Animal-Origin-Free Culture Medium. Viruses 2023; 15:2152. [PMID: 38005830 PMCID: PMC10674172 DOI: 10.3390/v15112152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 10/12/2023] [Accepted: 10/23/2023] [Indexed: 11/26/2023] Open
Abstract
Adenoviruses are promising vectors for vaccine production and gene therapy. Despite all the efforts in removing animal-derived components such as fetal bovine serum (FBS) during the production of adenovirus vector (AdV), FBS is still frequently employed in the early stages of production. Conventionally, first-generation AdVs (E1 deleted) are generated in different variants of adherent HEK293 cells, and plaque purification (if needed) is performed in adherent cell lines in the presence of FBS. In this study, we generated an AdV stock in SF-BMAdR (A549 cells adapted to suspension culture in serum-free medium). We also developed a limiting dilution method using the same cell line to replace the plaque purification assay. By combining these two technologies, we were able to completely remove the need for FBS from the process of generating and producing AdVs. In addition, we demonstrated that the purified AdV stock is free of any replication-competent adenovirus (RCA). Furthermore, we demonstrated that our limiting dilution method could effectively rescue an AdV from a stock that is highly contaminated with RCA.
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BCG administration promotes the long-term protection afforded by a single-dose intranasal adenovirus-based SARS-CoV-2 vaccine. iScience 2023; 26:107612. [PMID: 37670783 PMCID: PMC10475483 DOI: 10.1016/j.isci.2023.107612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2023] [Revised: 07/19/2023] [Accepted: 08/09/2023] [Indexed: 09/07/2023] Open
Abstract
Recent publications have explored intranasal (i.n.) adenovirus-based (Ad) vaccines as an effective strategy for SARS-CoV-2 in pre-clinical models. However, the effects of prior immunizations and infections have yet to be considered. Here, we investigate the immunomodulatory effects of Mycobacterium bovis BCG pre-immunization followed by vaccination with an S-protein-expressing i.n. Ad, termed Ad(Spike). While i.n. Ad(Spike) retains some protective effect after 6 months, a single administration of BCG-Danish prior to Ad(Spike) potentiates its ability to control viral replication of the B.1.351 SARS-CoV-2 variant within the respiratory tract. Though BCG-Danish did not affect Ad(Spike)-generated humoral immunity, it promoted the generation of cytotoxic/Th1 responses over suppressive FoxP3+ TREG cells in the lungs of infected mice. Thus, this vaccination strategy may prove useful in limiting future pandemics by potentiating the long-term efficacy of mucosal vaccines within the context of the widely distributed BCG vaccine.
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Inducible HEK293 AAV packaging cell lines expressing Rep proteins. Mol Ther Methods Clin Dev 2023; 30:259-275. [PMID: 37560197 PMCID: PMC10407821 DOI: 10.1016/j.omtm.2023.07.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Accepted: 07/11/2023] [Indexed: 08/11/2023]
Abstract
Packaging or producer cell lines for scalable recombinant adeno-associated virus (rAAV) production have been notoriously difficult to create due in part to the cytostatic nature of the Rep proteins required for AAV production. The most difficult challenge being creating AAV packaging cell lines using HEK293 parental cells, currently the best mammalian platform for rAAV production due to the constitutive expression of E1A in HEK293 cells, a key REP transcription activator. Using suspension and serum-free media adapted HEK293SF carrying a gene expression regulation system induced by addition of cumate and coumermycin, we were able to create REP-expressing AAV packaging cells. This was achieved by carefully choosing two of the AAV Rep proteins (Rep 40 and 68), using two inducible promoters with different expression levels and integrating into the cells through lentiviral vector transduction. Three of our best clones produced rAAV titers comparable to titers obtained by standard triple plasmid transfection of their parental cells. These clones were stable for up to 7 weeks under continuous cultures condition. rAAV production from one clone was also validated at scale of 1 L in a wave bioreactor using serum-free suspension culture.
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Protease-deleted adenovirus as an alternative for replication-competent adenovirus vector. Virology 2023; 586:67-75. [PMID: 37487327 DOI: 10.1016/j.virol.2023.07.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 06/22/2023] [Accepted: 07/11/2023] [Indexed: 07/26/2023]
Abstract
For cancer therapy and vaccination an amplified expression of the therapeutic gene is desired. Previously, we have developed a single-cycle adenovirus vector (SC-AdV) by deleting the adenovirus protease (PS) gene. In order to keep the E1 region intact within the PS-deleted adenoviruses, we examined the insertion of two transgenes under the control of a constitutive or inducible promoters. These were inserted between E4 and the right inverted terminal repeat in a wide variety of backbones with various combinations of PS, E3 and E4 deletion. Our data showed that PS-deleted adenoviruses, expressed transgenes as strongly as replication-competent AdVs in HEK293A and a variant of HeLa cells. In a head-to-head comparison in four human cell lines, we demonstrated that SC-AdV, was comparable for transgene expression efficacy with its replication-competent counterpart. However, the SC-AdV expresses its transgene 10 to 16,000 times higher than its replication-defective counterpart.
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Preclinical Development and Characterization of Novel Adeno-Associated Viral Vectors for the Treatment of Lipoprotein Lipase Deficiency. Hum Gene Ther 2023; 34:927-946. [PMID: 37597209 DOI: 10.1089/hum.2023.075] [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] [Indexed: 08/21/2023] Open
Abstract
Lipoprotein lipase deficiency (LPLD) results from mutations within the lipoprotein lipase (LPL) gene that lead to a complete lack of catalytically active LPL protein. Glybera was one of the first adeno-associated virus (AAV) gene replacement therapy to receive European Medicines Agency regulatory approval for the treatment of LPLD. However, Glybera is no longer marketed potentially due to a combination of economical, manufacturing, and vector-related issues. The aim of this study was to develop a more efficacious AAV gene therapy vector for LPLD. Following preclinical biodistribution, efficacy and non-Good Laboratory Practice toxicity studies with novel AAV1 and AAV8-based vectors in mice, we identified AAV8 pVR59. AAV8 pVR59 delivered a codon-optimized, human gain-of-function hLPLS447X transgene driven by a CAG promoter in an AAV8 capsid. AAV8 pVR59 was significantly more efficacious, at 10- to 100-fold lower doses, compared with an AAV1 vector based on Glybera, when delivered intramuscularly or intravenously, respectively, in mice with LPLD. Efficient gene transfer was observed within the injected skeletal muscle and liver following delivery of AAV8 pVR59, with long-term correction of LPLD phenotypes, including normalization of plasma triglycerides and lipid tolerance, for up to 6 months post-treatment. While intramuscular delivery of AAV8 pVR59 was well tolerated, intravenous administration augmented liver pathology. These results highlight the feasibility of developing a superior AAV vector for the treatment of LPLD and provide critical insight for initiating studies in larger animal models. The identification of an AAV gene therapy vector that is more efficacious at lower doses, when paired with recent advances in production and manufacturing technologies, will ultimately translate to increased safety and accessibility for patients.
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Packaging cells for lentiviral vectors generated using the cumate and coumermycin gene induction systems and nanowell single-cell cloning. Mol Ther Methods Clin Dev 2023; 29:40-57. [PMID: 36936448 PMCID: PMC10018046 DOI: 10.1016/j.omtm.2023.02.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Accepted: 02/22/2023] [Indexed: 02/27/2023]
Abstract
Lentiviral vectors (LVs) are important for cell therapy because of their capacity to stably modify the genome after integration. This study describes a novel and relatively simple approach to generate packaging cells and producer clones for self-inactivating (SIN) LVs pseudotyped with the vesicular stomatitis virus glycoprotein (VSV-G). A novel gene regulation system, based on the combination of the cumate and coumermycin induction systems, was developed to ensure tight control for the expression of cytotoxic packaging elements. To accelerate clone isolation and ensure monoclonality, the packaging genes were transfected simultaneously into human embryonic kidney cells (293SF-3F6) previously engineered with the induction system, and clones were isolated after limiting dilution into nanowell arrays using a robotic cell picking instrument with scanning capability. The method's effectiveness to isolate colonies derived from single cells was demonstrated using mixed populations of cells labeled with two different fluorescent markers. Because the recipient cell line grew in suspension culture, and all the procedures were performed without serum, the resulting clones were readily adaptable to serum-free suspension culture. The best producer clone produced LVs expressing GFP at a titer of 2.3 × 108 transduction units (TU)/mL in the culture medium under batch mode without concentration.
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Programmable Attenuation of Antigenic Sensitivity for a Nanobody-Based EGFR Chimeric Antigen Receptor Through Hinge Domain Truncation. Front Immunol 2022; 13:864868. [PMID: 35935988 PMCID: PMC9354126 DOI: 10.3389/fimmu.2022.864868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 06/06/2022] [Indexed: 11/13/2022] Open
Abstract
Epidermal growth factor family receptor (EGFR) is commonly overexpressed in many solid tumors and an attractive target for chimeric antigen receptor (CAR)-T therapy, but as EGFR is also expressed at lower levels in healthy tissues a therapeutic strategy must balance antigenic responsiveness against the risk of on-target off-tumor toxicity. Herein, we identify several camelid single-domain antibodies (also known as nanobodies) that are effective EGFR targeting moieties for CARs (EGFR-sdCARs) with very strong reactivity to EGFR-high and EGFR-low target cells. As a strategy to attenuate their potent antigenic sensitivity, we performed progressive truncation of the human CD8 hinge commonly used as a spacer domain in many CAR constructs. Single amino acid hinge-domain truncation progressively decreased both EGFR-sdCAR-Jurkat cell binding to EGFR-expressing targets and expression of the CD69 activation marker. Attenuated signaling in hinge-truncated EGFR-sdCAR constructs increased selectivity for antigen-dense EGFR-overexpressing cells over an EGFR-low tumor cell line or healthy donor derived EGFR-positive fibroblasts. We also provide evidence that epitope location is critical for determining hinge-domain requirement for CARs, as hinge truncation similarly decreased antigenic sensitivity of a membrane-proximal epitope targeting HER2-CAR but not a membrane-distal EGFRvIII-specific CAR. Hinge-modified EGFR-sdCAR cells showed clear functional attenuation in Jurkat-CAR-T cells and primary human CAR-T cells from multiple donors in vitro and in vivo. Overall, these results indicate that hinge length tuning provides a programmable strategy for throttling antigenic sensitivity in CARs targeting membrane-proximal epitopes, and could be employed for CAR-optimization and improved tumor selectivity.
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A low dose adenovirus vectored vaccine expressing Schistosoma mansoni Cathepsin B protects from intestinal schistosomiasis in mice. EBioMedicine 2022; 80:104036. [PMID: 35500538 PMCID: PMC9065910 DOI: 10.1016/j.ebiom.2022.104036] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 03/30/2022] [Accepted: 04/16/2022] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND Schistosomiasis is an underestimated neglected tropical disease which affects over 236.6 million people worldwide. According to the CDC, the impact of this disease is second to only malaria as the most devastating parasitic infection. Affected individuals manifest chronic pathology due to egg granuloma formation, destroying the liver over time. The only FDA approved drug, praziquantel, does not protect individuals from reinfection, highlighting the need for a prophylactic vaccine. Schistosoma mansoni Cathepsin B (SmCB) is a parasitic gut peptidase necessary for helminth growth and maturation and confers protection as a vaccine target for intestinal schistosomiasis. METHODS An SmCB expressing human adenovirus serotype 5 (AdSmCB) was constructed and delivered intramuscularly to female C57BL/6 mice in a heterologous prime and boost vaccine with recombinant protein. Vaccine induced immunity was described and subsequent protection from parasite infection was assessed by analysing parasite burden and liver pathology. FINDINGS Substantially higher humoral and cell-mediated immune responses, consisting of IgG2c, Th1 effectors, and polyfunctional CD4+ T cells, were induced by the heterologous administration of AdSmCB when compared to the other regimens. Though immune responses favoured Th1 immunity, Th2 responses provided by SmCB protein boosts were maintained. This mixed Th1/Th2 immune response resulted in significant protection from S. mansoni infection comparable to other vaccine formulations which are in clinical trials. Schistosomiasis associated liver pathology was also prevented in a murine model. INTERPRETATION Our study provides missing preclinical data supporting the use of adenoviral vectoring in vaccines for S. mansoni infection. Our vaccination method significantly reduces parasite burden and its associated liver pathology - both of which are critical considerations for this helminth vaccine. FUNDING This work was supported by the Canadian Institutes of Health Research, R. Howard Webster Foundation, and the Foundation of the McGill University Health Centre.
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2021 Canadian Surgery Forum01. Design and validation of a unique endoscopy simulator using a commercial video game03. Is ethnicity an appropriate measure of health care marginalization?: A systematic review and meta-analysis of the outcomes of diabetic foot ulceration in the Aboriginal population04. Racial disparities in surgery — a cross-specialty matched comparison between black and white patients05. Starting late does not increase the risk of postoperative complications in patients undergoing common general surgical procedures06. Ethical decision-making during a health care crisis: a resource allocation framework and tool07. Ensuring stability in surgical training program leadership: a survey of program directors08. Introducing oncoplastic breast surgery in a community hospital09. Leadership development programs for surgical residents: a review of the literature10. Superiority of non-opioid postoperative pain management after thyroid and parathyroid operations: a systematic review and meta-analysis11. Timing of ERCP relative to cholecystectomy in patients with ductal gallstone disease12. A systematic review and meta-analysis of randomized controlled trials comparing intraoperative red blood cell transfusion strategies13. Postoperative outcomes after frail elderly preoperative assessment clinic: a single-institution Canadian perspective14. Selective opioid antagonists following bowel resection for prevention of postoperative ileus: a systematic review and meta-analysis15. Peer-to-peer coaching after bile duct injury16. Laparoscopic median arcuate ligament release: a video abstract17. Retroperitoneoscopic approach to adrenalectomy19. Endoscopic Zenker diverticulotomy: a video abstract20. Variability in surgeons’ perioperative management of pheochromocytomas in Canada21. The contribution of surgeon and hospital variation in transfusion practice to outcomes for patients undergoing elective gastrointestinal cancer surgery: a population-based analysis22. Perioperative transfusions for gastroesophageal cancers: risk factors and short- and long-term outcomes23. The association between frailty and time alive and at home after cancer surgery among older adults: a population-based analysis24. Psychological and workplace-related effects of providing surgical care during the COVID-19 pandemic in British Columbia, Canada25. Safety of venous thromboembolism prophylaxis in endoscopic retrograde cholangiopancreatography: a systematic review26. Complications and reintervention following laparoscopic subtotal cholecystectomy: a systematic review and meta-analysis27. Synchronization of pupil dilations correlates with team performance in a simulated laparoscopic team coordination task28. Receptivity to and desired design features of a surgical peer coaching program: an international survey9. Impact of the COVID-19 pandemic on rates of emergency department utilization due to general surgery conditions30. The impact of the current COVID-19 pandemic on the exposure of general surgery trainees to operative procedures31. Association between academic degrees and research productivity: an assessment of academic general surgeons in Canada32. Laparoscopic endoscopic cooperative surgery (LECS) for subepithelial gastric lesion: a video presentation33. Effect of the COVID-19 pandemic on acute care general surgery at an academic Canadian centre34. Opioid-free analgesia after outpatient general surgery: a pilot randomized controlled trial35. Impact of neoadjuvant immunotherapy or targeted therapies on surgical resection in patients with solid tumours: a systematic review and meta-analysis37. Surgical data recording in the operating room: a systematic review of modalities and metrics38. Association between nonaccidental trauma and neighbourhood socioeconomic status during the COVID-19 pandemic: a retrospective analysis39. Laparoscopic repair of a transdiaphragmatic gastropleural fistula40. Video-based interviewing in medicine: a scoping review41. Indocyanine green fluorescence angiography for prevention of anastomotic leakage in colorectal surgery: a cost analysis from the hospital payer’s perspective43. Perception or reality: surgical resident and faculty assessments of resident workload compared with objective data45. When illness and loss hit close to home: Do health care providers learn how to cope?46. Remote video-based suturing education with smartphones (REVISE): a randomized controlled trial47. The evolving use of robotic surgery: a population-based analysis48. Prophylactic retromuscular mesh placement for parastomal hernia prevention: a retrospective cohort study of permanent colostomies and ileostomies49. Intracorporeal versus extracorporeal anastomosis in laparoscopic right hemicolectomy: a retrospective cohort study on anastomotic complications50. A lay of the land — a description of Canadian academic acute care surgery models51. Emergency general surgery in Ontario: interhospital variability in structures, processes and models of care52. Trauma 101: a virtual case-based trauma conference as an adjunct to medical education53. Assessment of the National Surgical Quality Improvement Program Surgical Risk Calculator for predicting patient-centred outcomes of emergency general surgery patients in a Canadian health care system54. Sustainability of a narcotic reduction initiative: 1 year following the Standardization of Outpatient Procedure (STOP) Narcotics Study55. Barriers to transanal endoscopic microsurgery referral56. Geospatial analysis of severely injured rural patients in a geographically complex landscape57. Implementation of an incentive spirometry protocol in a trauma ward: a single-centre pilot study58. Impostor phenomenon is a significant risk factor for burnout and anxiety in Canadian resident physicians: a cross-sectional survey59. Understanding the influence of perioperative education on performance among surgical trainees: a single-centre experience60. The effect of COVID-19 pandemic on current and future endoscopic personal protective equipment practices: a national survey of 77 endoscopists61. Case report: delayed presentation of perforated sigmoid diverticulitis as necrotizing infection of the lower limb62. Investigating disparities in surgical outcomes in Canadian Indigenous populations63. Fundoplication is superior to medical therapy for Barrett esophagus disease regression and progression: a systematic review and meta-analysis64. Development of a novel online general surgery learning platform and a qualitative preimplementation analysis65. Hagfish slime exudate as a potential novel hemostatic agent: developing a standardized assessment protocol66. The effect of the first wave of the COVID-19 pandemic on surgical oncology case volumes and wait times67. Safety of same-day discharge in high-risk patients undergoing ambulatory general surgery68. External validation of the Codman score in colorectal surgery: a pragmatic tool to drive quality improvement69. Improved morbidity and gastrointestinal restoration rates without compromising survival rates for diverting loop ileostomy with colonic lavage versus total abdominal colectomy for fulminant Clostridioides difficile colitis: a multicentre retrospective cohort study70. Potential access to emergency general surgical care in Ontario71. Immersive virtual reality (iVR) improves procedural duration, task completion and accuracy in surgical trainees: a systematic review01. Clinical validation of the Canada Lymph Node Score for endobronchial ultrasound02. Venous thromboembolism in surgically treated esophageal cancer patients: a provincial population-based study03. Venous thromboembolism in surgically treated lung cancer patients: a population-based study04. Is frailty associated with failure to rescue after esophagectomy? A multi-institutional comparative analysis of outcomes05. Routine systematic sampling versus targeted sampling of lymph nodes during endobronchial ultrasound: a feasibility randomized controlled trial06. Gastric ischemic conditioning reduces anastomotic complications in patients undergoing esophagectomy: a systematic review and meta-analysis07. Move For Surgery, a novel preconditioning program to optimize health before thoracic surgery: a randomized controlled trial08. In case of emergency, go to your nearest emergency department — Or maybe not?09. Does preoperative SABR increase the risk of complications from lung cancer resection? A secondary analysis of the MISSILE trial10. Segmental resection for lung cancer: the added value of near-infrared fluorescence mapping diminishes with surgeon experience11. Toward competency-based continuing professional development for practising surgeons12. Stereotactic body radiotherapy versus surgery in older adults with NSCLC — a population-based, matched analysis of long-term dependency outcomes13. Role of adjuvant therapy in esophageal cancer patients after neoadjuvant therapy and curative esophagectomy: a systematic review and meta-analysis14. Evaluation of population characteristics on the incidence of thoracic empyema: an ecological study15. Determining the optimal stiffness colour threshold and stiffness area ratio cut-off for mediastinal lymph node staging using EBUS elastography and AI: a pilot study16. Quality assurance on the use of sequential compression stockings in thoracic surgery (QUESTs)17. The relationship between fissureless technique and prolonged air leak for patients undergoing video-assisted thoracoscopic lobectomy18. CXCR2 inhibition as a candidate for immunomodulation in the treatment of K-RAS-driven lung adenocarcinoma19. Assessment tools for evaluating competency in video-assisted thoracoscopic lobectomy: a systematic review20. Understanding the current practice on chest tube management following lung resection among thoracic surgeons across Canada21. Effect of routine jejunostomy tube insertion in esophagectomy: a systematic review and meta-analysis22. Recurrence of primary spontaneous pneumothorax following bullectomy with pleurodesis or pleurectomy: a retrospective analysis23. Surgical outcomes following chest wall resection and reconstruction24. Outcomes following surgical management of primary mediastinal nonseminomatous germ cell tumours25. Does robotic approach offer better nodal staging than thoracoscopic approach in anatomical resection for non–small cell lung cancer? A single-centre propensity matching analysis26. Competency assessment for mediastinal mass resection and thymectomy: design and Delphi process27. The contemporary significance of venous thromboembolism (deep venous thrombosis [DVT] and pulmonary embolus [PE]) in patients undergoing esophagectomy: a prospective, multicentre cohort study to evaluate the incidence and clinical outcomes of VTE after major esophageal resections28. Esophageal cancer: symptom severity at the end of life29. The impact of pulmonary artery reconstruction on postoperative and oncologic outcomes: a systematic review30. Association with surgical technique and recurrence after laparoscopic repair of paraesophageal hernia: a single-centre experience31. Enhanced recovery after surgery (ERAS) in esophagectomy32. Surgical treatment of esophageal cancer: trends in surgical approach and early mortality at a single institution over the past 18 years34. Adverse events and length of stay following minimally invasive surgery in paraesophageal hernia repair35. Long-term symptom control comparison of Dor and Nissen fundoplication following laparoscopic para-esophageal hernia repair: a retrospective analysis36. Willingness to pay: a survey of Canadian patients’ willingness to contribute to the cost of robotic thoracic surgery37. Radiomics in early-stage lung adenocarcinoma: a prediction tool for tumour immune microenvironments38. Effectiveness of intraoperative pyloric botox injection during esophagectomy: how often is endoscopic intervention required?39. An artificial intelligence algorithm for predicting lymph node malignancy during endobronchial ultrasound40. The effect of major and minor complications after lung surgery on length of stay and readmission41. Measuring cost of adverse events following thoracic surgery: a scoping review42. Laparoscopic paraesophageal hernia repair: characterization by hospital and surgeon volume and impact on outcomes43. NSQIP 5-Factor Modified Frailty Index predicts morbidity but not mortality after esophagectomy44. Trajectory of perioperative HRQOL and association with postoperative complications in thoracic surgery patients45. Variation in treatment patterns and outcomes for resected esophageal cancer at designated thoracic surgery centres46. Patient-reported pretreatment health-related quality of life (HRQOL) predicts short-term survival in esophageal cancer patients47. Analgesic efficacy of surgeon-placed paravertebral catheters compared with thoracic epidural analgesia after Ivor Lewis esophagectomy: a retrospective noninferiority study48. Rapid return to normal oxygenation after lung surgery49. Examination of local and systemic inflammatory changes during lung surgery01. Implications of near-infrared imaging and indocyanine green on anastomotic leaks following colorectal surgery: a systematic review and meta-analysis02. Repeat preoperative endoscopy after regional implementation of electronic synoptic endoscopy reporting: a retrospective comparative study03. Consensus-derived quality indicators for operative reporting in transanal endoscopic surgery (TES)04. Colorectal lesion localization practices at endoscopy to facilitate surgical and endoscopic planning: recommendations from a national consensus Delphi process05. Black race is associated with increased mortality in colon cancer — a population-based and propensity-score matched analysis06. Improved survival in a cohort of patients 75 years and over with FIT-detected colorectal neoplasms07. Laparoscopic versus open loop ileostomy reversal: a systematic review and meta-analysis08. Posterior mesorectal thickness as a predictor of increased operative time in rectal cancer surgery: a retrospective cohort study09. Improvement of colonic anastomotic healing in mice with oral supplementation of oligosaccharides10. How can we better identify patients with rectal bleeding who are at high risk of colorectal cancer?11. Assessment of long-term bowel dysfunction in rectal cancer survivors: a population-based cohort study12. Observational versus antibiotic therapy for acute uncomplicated diverticulitis: a noninferiority meta-analysis based on a Delphi consensus13. Radiotherapy alone versus chemoradiotherapy for stage I anal squamous cell carcinoma: a systematic review and meta-analysis14. Is the Hartmann procedure for diverticulitis obsolete? National trends in colectomy for diverticulitis in the emergency setting from 1993 to 201515. Sugammadex in colorectal surgery: a systematic review and meta-analysis16. Sexuality and rectal cancer treatment: a qualitative study exploring patients’ information needs and expectations on sexual dysfunction after rectal cancer treatment17. Video-based interviews in selection process18. Impact of delaying colonoscopies during the COVID-19 pandemic on colorectal cancer detection and prevention19. Opioid use disorder associated with increased anastomotic leak and major complications after colorectal surgery20. Effectiveness of a rectal cancer education video on patient expectations21. Robotic-assisted rectosigmoid and rectal cancer resection: implementation and early experience at a Canadian tertiary centre22. An online educational app for rectal cancer survivors with low anterior resection syndrome: a pilot study23. The effects of surgeon specialization on the outcome of emergency colorectal surgery24. Outcomes after colorectal cancer resections in octogenarians and older in a regional New Zealand setting — What are the predictors of mortality?25. Long-term outcomes after seton placement for perianal fistulae with and without Crohn disease26. A survey of patient and surgeon preference for early ileostomy closure following restorative proctectomy for rectal cancer — Why aren’t we doing it?27. Crohn disease independently associated with longer hospital admission after surgery28. Short-stay (≤ 1 d) diverting loop ileostomy closure can be selectively implemented without an increase in readmission and complication rates: an ACS-NSQIP analysis29. A comparison of perineal stapled rectal prolapse resection and the Altemeier procedure at 2 Canadian academic hospitals30. Mental health and substance use disorders predict 90-day readmission and postoperative complications following rectal cancer surgery31. Early discharge after colorectal cancer resection: trends and impact on patient outcomes32. Oral antibiotics without mechanical bowel preparation prior to emergency colectomy reduces the risk of organ space surgical site infections: a NSQIP propensity score matched study33. The impact of robotic surgery on a tertiary care colorectal surgery program, an assessment of costs and short-term outcomes — a Canadian perspective34. Should we scope beyond the age limit of guidelines? Adenoma detection rates and outcomes of screening and surveillance colonoscopies in patients aged 75–79 years35. Emergency department admissions for uncomplicated diverticulitis: a nationwide study36. Obesity is associated with a complicated episode of acute diverticulitis: a nationwide study37. Green indocyanine angiography for low anterior resection in patients with rectal cancer: a prospective before-and-after study38. The impact of age on surgical recurrence of fibrostenotic ileocolic Crohn disease39. A qualitative study to explore the optimal timing and approach for the LARS discussion01. Racial, ethnic and socioeconomic disparities in diagnosis, treatment and survival of patients with breast cancer: a SEER-based population analysis02. First-line palliative chemotherapy for esophageal and gastric cancer: practice patterns and outcomes in the general population03. Frailty as a predictor for postoperative outcomes following pancreaticoduodenectomy04. Synoptic electronic operative reports identify practice variation in cancer surgery allowing for directed interventions to decrease variation05. The role of Hedgehog signalling in basal-like breast cancer07. Clinical and patient-reported outcomes in oncoplastic breast conservation surgery from a single surgeon’s practice in a busy community hospital in Canada08. Upgrade rate of atypical ductal hyperplasia: 10 years of experience and predictive factors09. Time to first adjuvant treatment after oncoplastic breast reduction10. Preparing to survive: improving outcomes for young women with breast cancer11. Opioid prescription and consumption in patients undergoing outpatient breast surgery — baseline data for a quality improvement initiative12. Rectal anastomosis and hyperthermic intraperitoneal chemotherapy: Should we avoid diverting loop ileostomy?13. Delays in operative management of early-stage, estrogen-receptor positive breast cancer during the COVID-19 pandemic — a multi-institutional matched historical cohort study14. Opioid prescribing practices in breast oncologic surgery15. Oncoplastic breast reduction (OBR) complications and patient-reported outcomes16. De-escalating breast cancer surgery: Should we apply quality indicators from other jurisdictions in Canada?17. The breast cancer patient experience of telemedicine during COVID-1918. A novel ex vivo human peritoneal model to investigate mechanisms of peritoneal metastasis in gastric adenocarcinoma (GCa)19. Preliminary uptake and outcomes utilizing the BREAST-Q patient-reported outcomes questionnaire in patients following breast cancer surgery20. Routine elastin staining improves detection of venous invasion and enhances prognostication in resected colorectal cancer21. Analysis of exhaled volatile organic compounds: a new frontier in colon cancer screening and surveillance22. A clinical pathway for radical cystectomy leads to a shorter hospital stay and decreases 30-day postoperative complications: a NSQIP analysis23. Fertility preservation in young breast cancer patients: a population-based study24. Investigating factors associated with postmastectomy unplanned emergency department visits: a population-based analysis25. Impact of patient, tumour and treatment factors on psychosocial outcomes after treatment in women with invasive breast cancer26. The relationship between breast and axillary pathologic complete response in women receiving neoadjuvant chemotherapy for breast cancer01. The association between bacterobilia and the risk of postoperative complications following pancreaticoduodenectomy02. Surgical outcome and quality of life following exercise-based prehabilitation for hepatobiliary surgery: a systematic review and meta-analysis03. Does intraoperative frozen section and revision of margins lead to improved survival in patients undergoing resection of perihilar cholangiocarcinoma? A systematic review and meta-analysis04. Prolonged kidney procurement time is associated with worse graft survival after transplantation05. Venous thromboembolism following hepatectomy for colorectal metastases: a population-based retrospective cohort study06. Association between resection approach and transfusion exposure in liver resection for gastrointestinal cancer07. The association between surgeon volume and use of laparoscopic liver resection for gastrointestinal cancer08. Immune suppression through TIGIT in colorectal cancer liver metastases09. “The whole is greater than the sum of its parts” — a combined strategy to reduce postoperative pancreatic fistula after pancreaticoduodenectomy10. Laparoscopic versus open synchronous colorectal and hepatic resection for metastatic colorectal cancer11. Identifying prognostic factors for overall survival in patients with recurrent disease following liver resection for colorectal cancer metastasis12. Modified Blumgart pancreatojejunostomy with external stenting in laparoscopic Whipple reconstruction13. Laparoscopic versus open pancreaticoduodenectomy: a single centre’s initial experience with introduction of a novel surgical approach14. Neoadjuvant chemotherapy versus upfront surgery for borderline resectable pancreatic cancer: a single-centre cohort analysis15. Thermal ablation and telemedicine to reduce resource utilization during the COVID-19 pandemic16. Cost-utility analysis of normothermic machine perfusion compared with static cold storage in liver transplantation in the Canadian setting17. Impact of adjuvant therapy on overall survival in early-stage ampullary cancers: a single-centre retrospective review18. Presence of biliary anaerobes enhances response to neoadjuvant chemotherapy in pancreatic ductal adenocarcinoma19. How does tumour viability influence the predictive capability of the Metroticket model? Comparing predicted-to-observed 5-year survival after liver transplant for hepatocellular carcinoma20. Does caudate resection improve outcomes in patients undergoing curative resection for perihilar cholangiocarcinoma? A systematic review and meta-analysis21. Appraisal of multivariable prognostic models for postoperative liver decompensation following partial hepatectomy: a systematic review22. Predictors of postoperative liver decompensation events following resection in patients with cirrhosis and hepatocellular carcinoma: a population-based study23. Characteristics of bacteriobilia and impact on outcomes after Whipple procedure01. Inverting the y-axis: the future of MIS abdominal wall reconstruction is upside down02. Progressive preoperative pneumoperitoneum: a single-centre retrospective study03. The role of radiologic classification of parastomal hernia as a predictor of the need for surgical hernia repair: a retrospective cohort study04. Comparison of 2 fascial defect closure methods for laparoscopic incisional hernia repair01. Hypoalbuminemia predicts serious complications following elective bariatric surgery02. Laparoscopic adjustable gastric band migration inducing jejunal obstruction associated with acute pancreatitis: aurgical approach of band removal03. Can visceral adipose tissue gene expression determine metabolic outcomes after bariatric surgery?04. Improvement of kidney function in patients with chronic kidney disease and severe obesity after bariatric surgery: a systematic review and meta-analysis05. A prediction model for delayed discharge following gastric bypass surgery06. Experiences and outcomes of Indigenous patients undergoing bariatric surgery: a mixed-methods scoping review07. What is the optimal common channel length in revisional bariatric surgery?08. Laparoscopic management of internal hernia in a 34-week pregnant woman09. Characterizing timing of postoperative complications following elective Roux-en-Y gastric bypass and sleeve gastrectomy10. Canadian trends in bariatric surgery11. Common surgical stapler problems and how to correct them12. Management of choledocholithiasis following Roux-en-Y gastric bypass: a systematic review and meta-analysis. Can J Surg 2021; 64:S80-S159. [PMID: 35483046 PMCID: PMC8677574 DOI: 10.1503/cjs.021321] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Production and Use of Gesicles for Nucleic Acid Delivery. Mol Biotechnol 2021; 64:278-292. [PMID: 34596870 DOI: 10.1007/s12033-021-00389-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2020] [Accepted: 09/08/2021] [Indexed: 12/29/2022]
Abstract
Over-expression of the vesicular stomatitis virus glycoprotein (VSVG) in mammalian cells can induce the formation of VSVG-pseudotyped vesicles (named "gesicles") from membrane budding. Its use as a nucleic acid delivery tool is still poorly documented. Naked-plasmid DNA can be delivered in animal cells with gesicles in presence of hexadimethrine bromide (polybrene). However, little is known about gesicle manufacturing process and conditions to obtain successful nucleic acid delivery. In this study, gesicles production process using polyethylenimine (PEI)-transfected HEK293 cells was developed by defining the VSVG-plasmid concentration, the DNA:PEI mass ratio, and the time of gesicle harvest. Furthermore, parameters described in the literature relevant for nucleic acid delivery such as (i) component concentrations in assembly mixture, (ii) component addition order, (iii) incubation time, and (iv) polybrene concentration were tested by assessing the transfection capacity of the gesicles complexed with a green fluorescent protein (GFP)-coding plasmid. Interestingly, freezing/thawing cycles and storage at + 4 °C, - 20 °C, and - 80 °C did not reduce gesicles' ability to transfer plasmid DNA. Transfection efficiency of 55% and 22% was obtained for HeLa cells and for hard-to-transfect cells such as human myoblasts, respectively. For the first time, gesicles were used for delivery of a large plasmid (18-kb) with 42% of efficiency and for enhanced green fluorescent protein (eGFP) gene silencing with siRNA (up to 60%). In conclusion, gesicles represent attractive bioreagents with great potential to deliver nucleic acids in mammalian cells.
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A rapid Focus-Forming Assay for quantification of infectious adenoviral vectors. J Virol Methods 2021; 297:114267. [PMID: 34437873 DOI: 10.1016/j.jviromet.2021.114267] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 08/09/2021] [Accepted: 08/20/2021] [Indexed: 12/23/2022]
Abstract
Currently available methods to titrate adenoviral vectors (AdV) in the absence of a gene reporter such as GFP, are either time-consuming or not very reproducible. A Focus-Forming Assay (FFA) for quantification of infectious AdV particles followed by automated focus counting was developed using new monoclonal antibodies (mAbs) against the human adenovirus type 5. Briefly, in this method, 96-well plates of HEK293A cells were infected with 2-fold dilutions of AdV at seeding time. Forty eight hours post-infection, the cells were fixed with methanol. The cells were then incubated with each mAb followed by a FITC conjugated anti-mouse antibody. The plates were scanned and positive cells counted using an automated fluorescence microscopy system. The results of the FFA were compared with the plaque assay and the TCID50 assay. The titer of six different recombinant AdV were compared using the FFA along with a commercial kit. The results were similar, but in contrast to the commercial kit for which the stained cells are counted manually, the software automatically counts the positives cells in the FFA. The automatic counting of positive cells makes the FFA a more precise and reliable assay compared to the commercial kit for titration of AdV.
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The Potential Impact and Usability of the Eighth Edition TNM Staging Classification in Oral Cavity Cancer. Clin Oncol (R Coll Radiol) 2021; 33:e442-e449. [PMID: 34261594 DOI: 10.1016/j.clon.2021.05.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 04/15/2021] [Accepted: 05/18/2021] [Indexed: 11/29/2022]
Abstract
AIMS In the current eighth edition head and neck TNM staging, extranodal extension (ENE) is an adverse feature in oral cavity squamous cell cancer (OSCC). The previous seventh edition N1 with ENE is now staged as N2a. Seventh edition N2+ with ENE is staged as N3b in the eighth edition. We evaluated its potential impact on patients treated with surgery and postoperative intensity-modulated radiotherapy (IMRT). MATERIALS AND METHODS OSCC patients treated with primary surgery and adjuvant (chemo)radiotherapy between January 2005 and December 2014 were reviewed. Cohorts with pathological node-negative (pN-), pathological node-positive without ENE (pN+_pENE-) and pathological node-positive with ENE (pN+_pENE+) diseases were compared for local control, regional control, distant control and overall survival. The pN+ cohorts were further stratified into seventh edition N-staging subgroups for outcomes comparison. RESULTS In total, 478 patients were evaluated: 173 pN-; 159 pN+_pENE-; 146 pN+_pENE+. Outcomes at 5 years were: local control was identical (78%) in all cohorts (P = 0.892), whereas regional control was 91%, 80% and 68%, respectively (P < 0.001). Distant control was 97%, 87%, 68% (P < 0.001) and overall survival was 75%, 53% and 39% (P < 0.001), respectively. Overall survival for N1 and N2a subgroups was not significantly different. In the seventh edition N2b subgroup of pENE- (n = 79) and pENE+ (n = 79) cohorts, overall survival was 67% and 37%, respectively. In the seventh edition N2c subgroups, overall survival for pENE- (n = 17) and pENE+ (n = 38) cohorts was 65% and 35% (P = 0.08), respectively. Overall, an additional 128 patients (42% pN+) were upstaged as N3b. CONCLUSIONS When eighth edition staging was applied, stage migration across the N2-3 categories resulted in expected larger separations of overall survival by stage. Patients treated with primary radiation without surgical staging should have outcomes carefully monitored. Strategies to predict ENE preoperatively and trials to improve the outcomes of pENE+ patients should be explored.
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3D-mapping of mesenchymal stem cells growth on bioengineered scaffolds for maxillofacial skeleton regeneration: a preclinical, in vitro study. Cytotherapy 2021. [DOI: 10.1016/s146532492100517x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Linking data on women in public family law court proceedings concerning their children to mental health service records in South London. Int J Popul Data Sci 2021; 6:1385. [PMID: 34036180 PMCID: PMC8133060 DOI: 10.23889/ijpds.v5i2.1385] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
INTRODUCTION Maternal mental health problems and substance misuse are key risk factors for child neglect or abuse and court-mandated placement into care. Linkage between mental health records and family court data could raise awareness about parent mental health needs and inform approaches to address them. OBJECTIVES To evaluate data linkage between administrative family court data and electronic mental health records for a population-based mental health service for 1.3 million people in South London. METHODS We deterministically linked administrative family court data for women (n=5463) involved in care proceedings in South London with service user records from the South London and Maudsley NHS Mental Health Trust (SLaM). We restricted the cohort to women involved in proceedings between 2007 and 2019, in local authorities where SLaM solely provides secondary/tertiary mental health services and the Improving Access to Psychological Therapies (IAPT) (n=3226). We analysed the associations between match status and sociodemographic/case characteristics using multivariable logistic regression. RESULTS Two-thirds (2317/3226; 66%) of women linked to a SLaM service user record at some point; most (91%) who linked accessed secondary/tertiary mental health services, indicating serious mental illness. Accounting for possible missed matches, we estimated that 70-83% of women accessed SLaM services at some point. Older women at index proceedings (>35yrs OR: 0.69, 95%CI: 0.54-0.88vs <25yrs) and Black women or women from other ethnic groups (Black ethnic groups 0.65, 0.50-0.83; other ethnicity 0.59, 0.43-0.81 vs White ethnic groups) had lower odds of linking. Odds of linking were higher for women with an infant in proceedings (1.42, 1.18-1.71), or with curtailed/terminated parental responsibility (1.44, 1.20-1.73). CONCLUSION Our linkage supports growing evidence of a high burden of mental health problems and substance misuse among women whose children enter care in England, compared to the general population. Research using this linkage should inform strategies to address the considerable mental health needs of vulnerable women and their children.
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Evaluation of novel HIV vaccine candidates using recombinant vesicular stomatitis virus vector produced in serum-free Vero cell cultures. Vaccine 2020; 38:7949-7955. [PMID: 33139138 DOI: 10.1016/j.vaccine.2020.10.058] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 10/09/2020] [Accepted: 10/18/2020] [Indexed: 12/20/2022]
Abstract
Acquired Immune Deficiency Syndrome (AIDS) in humans is a result of the destruction of the immune system caused by Human Immunodeficiency Virus (HIV) infection. This serious epidemic is still progressing world-wide. Despite advances in treatment, a safe and effective preventive HIV vaccine is desired to combat this disease, and to save millions of lives. However, such a vaccine is not available yet although extensive amounts of resources in research and development have been invested over three decades. In light of the recently approved Ebola virus disease vaccine based on a recombinant vesicular stomatitis virus (rVSV-ZEBOV), we present the results of our work on three novel VSV-vectored HIV vaccine candidates. We describe the design, rescue, production and purification method and evaluate their immunogenicity in mice prior to preclinical studies that will be performed in non-human primates. The production of each of the three candidate vaccines (rVSV-B6-NL4.3Env/SIVtm, rVSV-B6-NL4.3Env/Ebtm and rVSV-B6-A74Env(PN6)/SIVtm) was evaluated in small scale in Vero cells and it was found that production kinetics on Vero cells vary depending on the HIV gp surface protein used. Purified virus preparations complied with the WHO restrictions for the residual DNA and host cell protein contents. Finally, when administered to mice, all three rVSV-HIV vaccine candidates induced an HIV gp140-specific antibody response.
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Timing of paediatric orchidopexy in universal healthcare systems: international administrative data cohort study. BJS Open 2020; 4:1117-1124. [PMID: 32706149 PMCID: PMC7709362 DOI: 10.1002/bjs5.50329] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Accepted: 06/24/2020] [Indexed: 01/23/2023] Open
Abstract
BACKGROUND International guidelines in 2008 recommended orchidopexy for undescended testis at 6-12 months of age to reduce the risk of testicular cancer and infertility. Using administrative data from England, Finland, Ontario (Canada), Scotland and Sweden (with data from Victoria (Australia) and Iceland in supplementary analyses), the aim of this study was to investigate compliance with these guidelines and identify potential socioeconomic inequities in the timing of surgery before 1 and 3 years. METHODS All boys born in 2003-2011 with a diagnosis code of undescended testis and procedure codes indicating orchidopexy before their fifth birthday were identified from administrative health records. Trends in the proportion of orchidopexies performed before 1 and 3 years of age were investigated, as were socioeconomic inequities in adherence to the guidelines. RESULTS Across all jurisdictions, the proportion of orchidopexies occurring before the first birthday increased over the study period. By 2011, from 7·6 per cent (Sweden) to 27·9 per cent (Scotland) of boys had undergone orchidopexy by their first birthday and 71·5 per cent (Sweden) to 90·4 per cent (Scotland) by 3 years of age. There was limited evidence of socioeconomic inequities for orchidopexy before the introduction of guidelines (2008). Across all jurisdictions for boys born after 2008, there was consistent evidence of inequities in orchidopexy by the first birthday, favouring higher socioeconomic position. Absolute differences in these proportions between the highest and lowest socioeconomic groups ranged from 2·5 to 5·9 per cent across jurisdictions. CONCLUSION Consistent lack of adherence to the guidelines across jurisdictions questions whether the guidelines are appropriate.
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Data Resource: Children and Family Court Advisory and Support Service (Cafcass) public family law administrative records in England. Int J Popul Data Sci 2020; 5:1159. [PMID: 34232967 PMCID: PMC7482375 DOI: 10.23889/ijpds.v5i1.1159] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
Introduction In England, in cases of child maltreatment or neglect, the state can intervene through the family court to remove children from their family home and place them in out-of-home care. The Children and Family Court Advisory and Support Service (Cafcass) collects and maintains administrative records of all public family law cases in England. While these national records are primarily used to monitor and manage the workflow of Cafcass teams across England, researchers have re-purposed this data for analysis to understand the drivers and outcomes of public family law intervention. Data contents The administrative dataset is a reflection of the cases Cafcass is involved with and the extent of that involvement. The dataset contains information about the local authority that makes an application to initiate public family law proceedings, the children and families involved, and the duration and details of the case. Between 1 April 2007 and 31 March 2019, Cafcass captured information on approximately 172,100 public family law cases, involving 282,300 children, and 349,600 adults (of which 289,300 are recorded as biological parents). Amongst the information recorded are the relations between adults and children, making it possible for researchers to identify family groups. Additionally, recording practices at Cafcass have improved over time, this has increased the availability of demographic information of all those involved, as well as child's final legal outcome. Data access Researchers can apply to the Secure Anonymised Information Linkage databank (SAIL) for access to the Cafcass pseudonymised administrative data extract, where it is refreshed bi-annually. Keywords children, out of home care, family relations, family law.
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Abstract
The recombinant Vesicular Stomatitis Virus (rVSV) is an emerging platform for viral vector-based vaccines. Promising results have been reported in clinical trials for the rVSV-ZEBOV vaccine for Ebola virus disease prevention. In this study, we describe the titration tools elaborated to assess the titre of rVSV-ZEBOV productions. • A streamlined Median Tissue Culture Infectious Dose (TCID50) assay to determine the infectious titer of this vaccine was established. • A digital polymerase chain reaction (dPCR) assay to assess the total number of viral particles present in cell-free culture supernatants of rVSV productions was developed. • These assays are used to titre rVSV-ZEBOV samples and characterize the ratio of total particles to infectious units for monitoring process robustness and product quality attributes and can be used to titre samples generated in the production of further rVSV vectors.
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A High-Throughput Method for Characterizing Novel Chimeric Antigen Receptors in Jurkat Cells. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2020; 16:238-254. [PMID: 32083149 PMCID: PMC7021643 DOI: 10.1016/j.omtm.2020.01.012] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Accepted: 01/27/2020] [Indexed: 01/18/2023]
Abstract
Chimeric antigen receptor (CAR) development involves extensive empirical characterization of antigen-binding domain (ABD)/CAR constructs for clinical suitability. Here, we present a cost-efficient and rapid method for evaluating CARs in human Jurkat T cells. Using a modular CAR plasmid, a highly efficient ABD cloning strategy, plasmid electroporation, short-term co-culture, and flow-cytometric detection of CD69, this assay (referred to as CAR-J) evaluates sensitivity and specificity for ABDs. Assessing 16 novel anti-CD22 single-chain variable fragments derived from mouse monoclonal antibodies, CAR-J stratified constructs by response magnitude to CD22-expressing target cells. We also characterized 5 novel anti-EGFRvIII CARs for preclinical development, identifying candidates with varying tonic and target-specific activation characteristics. When evaluated in primary human T cells, tonic/auto-activating (without target cells) EGFRvIII-CARs induced target-independent proliferation, differentiation toward an effector phenotype, elevated activity against EGFRvIII-negative cells, and progressive loss of target-specific response upon in vitro re-challenge. These EGFRvIII CAR-T cells also showed anti-tumor activity in xenografted mice. In summary, CAR-J represents a straightforward method for high-throughput assessment of CAR constructs as genuine cell-associated antigen receptors that is particularly useful for generating large specificity datasets as well as potential downstream CAR optimization.
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Prevalence of Down's Syndrome in England, 1998-2013: Comparison of linked surveillance data and electronic health records. Int J Popul Data Sci 2020; 5:1157. [PMID: 32864476 PMCID: PMC7115985 DOI: 10.23889/ijpds.v5i1.1157] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
INTRODUCTION Disease registers and electronic health records are valuable resources for disease surveillance and research but can be limited by variation in data quality over time. Quality may be limited in terms of the accuracy of clinical information, of the internal linkage that supports person-based analysis of most administrative datasets, or by errors in linkage between multiple datasets. OBJECTIVES By linking the National Down Syndrome Cytogenetic Register (NDSCR) to Hospital Episode Statistics for England (HES), we aimed to assess the quality of each and establish a consistent approach for analysis of trends in prevalence of Down's syndrome among live births in England. METHODS Probabilistic record linkage of NDSCR to HES for the period 1998-2013 was supported by linkage of babies to mothers within HES. Comparison of prevalence estimates in England were made using NDSCR only, HES data only, and linked data. Capture-recapture analysis and quantitative bias analysis were used to account for potential errors, including false positive diagnostic codes, unrecorded diagnoses, and linkage error. RESULTS Analyses of single-source data indicated increasing live birth prevalence of Down's Syndrome, particularly in the analysis of HES. Linked data indicated a contrastingly stable prevalence of 12.3 (plausible range: 11.6-12.7) cases per 10 000 live births. CONCLUSION Case ascertainment in NDSCR improved slightly over time, creating a picture of slowly increasing prevalence. The emerging epidemic suggested by HES primarily reflects improving linkage within HES (assignment of unique patient identifiers to hospital episodes). Administrative data are valuable but trends should be interpreted with caution, and with assessment of data quality over time. Data linkage with quantitative bias analysis can provide more robust estimation and, in this case, stronger evidence that prevalence is not increasing. Routine linkage of administrative and register data can enhance the value of each.
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Impact of dextran sulfate in culture media on titration of vesicular stomatitis virus. J Virol Methods 2019; 275:113758. [PMID: 31678047 DOI: 10.1016/j.jviromet.2019.113758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Revised: 10/24/2019] [Accepted: 10/24/2019] [Indexed: 11/16/2022]
Abstract
Viral vectors derived from vesicular stomatitis virus (VSV) are important vectors for the development of vaccines and for the treatment of cancer. The efficiency of therapy based on VSV is dependent on the dose of virus used. Therefore it is essential to measure accurately and reproducibly the amount of functional vectors in the samples to be tested. Two common methods used to measure the titer of VSV are TCID50% and plaque assay. In the current study, we compared these two titration methods by using a recombinant VSV expressing the green fluorescent protein (VSV-GFP) as a model virus. Some culture media developed for suspension mammalian cells contain dextran sulfate. We observed that plaque assay, but not TCID50%, can underestimate the virus titer up to 10 fold when VSV-GFP was produced in culture media containing dextran sulfate. Dextran sulfate is commonly used in serum-free culture media to reduce cell aggregation in suspension culture. The inhibitory effect of dextran sulfate on the titration of VSV-GFP was confirmed by supplementing the culture medium with this compound during virus production. Our results also demonstrated that extending the incubation time during plaque assay and TCID50% increases virus titer.
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Evaluation of recombinant adenovirus vectors and adjuvanted protein as a heterologous prime-boost strategy using HER2 as a model antigen. Vaccine 2019; 37:7029-7040. [DOI: 10.1016/j.vaccine.2019.08.079] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Revised: 08/23/2019] [Accepted: 08/29/2019] [Indexed: 12/27/2022]
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Production of rVSV-ZEBOV in serum-free suspension culture of HEK 293SF cells. Vaccine 2019; 37:6624-6632. [DOI: 10.1016/j.vaccine.2019.09.044] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 08/28/2019] [Accepted: 09/11/2019] [Indexed: 12/13/2022]
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Three decades of inequality in neonatal and early childhood mortality in singleton births in Scotland. J Public Health (Oxf) 2019; 39:712-719. [PMID: 27784756 DOI: 10.1093/pubmed/fdw114] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Accepted: 09/13/2016] [Indexed: 11/12/2022] Open
Abstract
Background Socioeconomic inequality in child mortality highlights opportunities for policies to reduce child deaths. Methods We used singleton birth, death and maternity records from Scotland, 1981-2011, to examine mortality rate differences by age across deprivation quintiles over time. We measured the difference between the most and least deprived quintiles (Q5-Q1) and the slope index of inequality (SII) across all quintiles-measures of the absolute deprivation gap, providing an indication of the public health impact. Results Q5-Q1 remained relatively constant from 1990 onwards for early neonates, widened in the mid-2000s for late neonates, increased in the 1990 s then decreased in the 2000 s in the post-neonates and declined over time in early childhood. The trend over time in SII showed no significant change for early neonates (P = 0.440), significant decrease for post-neonates (P = 0.010) and early childhood (P = 0.043), and significant increase for late neonates (P = 0.011). Conclusions Over three decades, the absolute deprivation gap in mortality widened in late neonates but stabilized or declined at other ages. This may reflect improved survival beyond the early neonatal period of babies with conditions related to socioeconomic inequality such as prematurity. Monitoring birth cohort data could enhance understanding of this vulnerable group.
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Optimization of production of vesicular stomatitis virus (VSV) in suspension serum-free culture medium at high cell density. J Biotechnol 2018; 289:144-149. [PMID: 30508556 DOI: 10.1016/j.jbiotec.2018.11.023] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Revised: 11/08/2018] [Accepted: 11/27/2018] [Indexed: 12/22/2022]
Abstract
During the last decade, oncolytic viruses such as vesicular stomatitis virus (VSV) have gained tremendous popularity as efficient vaccines for infectious diseases as well as for the treatment of cancer. Our laboratory has developed two stable cell lines, 293SF-3F6 (derived from HEK293A cells) and SF-BMAdR cells (a variant of A549 that expresses the E1 region of human adenovirus). These two cell lines were adapted to grow efficiently in suspension culture and in serum-free medium. In this report we evaluated the production of a recombinant VSV expressing the green fluorescent protein (VSV-GFP) in these two stable cell lines. At a relatively low cell density of 500,000 cells per ml, 293SF-3F6 produced 4.6 times more infectious particles than SF-BMAdR cells. There was a positive correlation between volumetric virus titer and cell density up to 2.E + 07 cells/ml. A fed-batch process using an in-house medium and feed was developed to support the growth of 293SF-3F6 cells up to a concentration of 1.E + 07 cells/ml for infection at higher cell density and VSV production at high titer. Shifting the temperature from 37 °C to 34 °C at infection time improved VSV titer up to 3.3 fold. After scaling up the optimal condition from small scale (3 ml) to larger volumes (50 & 200 ml), the maximal volumetric titer obtained using the 293SF-3F6 cells was in average 2.9E + 10 extracellular infectious particles/ml. In conclusion, our data demonstrated that 293SF-3F6 cells, for which a cGMP master cell bank is available, is a performant cell line to scale up VSV production in suspension culture using serum-free medium.
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Associations between use of macrolide antibiotics during pregnancy and adverse child outcomes. Eur J Public Health 2018. [DOI: 10.1093/eurpub/cky218.225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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DELINEATING THE MECHANISMS THAT CONTRIBUTE TO REDUCED HEART FAILURE WITH EMPAGLIFLOZIN IN THE EXPERIMENTAL SETTING. Can J Cardiol 2018. [DOI: 10.1016/j.cjca.2018.07.130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Evaluating the effect of metronidazole plus amoxicillin-clavulanateversusamoxicillin-clavulanate alone in canine haemorrhagic diarrhoea: a randomised controlled trial in primary care practice. J Small Anim Pract 2018; 59:398-403. [DOI: 10.1111/jsap.12862] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Revised: 04/09/2018] [Accepted: 05/08/2018] [Indexed: 01/04/2023]
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Development of a recombinant murine tumour model using hepatoma cells expressing hepatitis C virus nonstructural antigens. J Viral Hepat 2018; 25:649-660. [PMID: 29316037 DOI: 10.1111/jvh.12856] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Accepted: 12/14/2017] [Indexed: 12/14/2022]
Abstract
Hepatitis C virus (HCV) chronically infects 2%-3% of the world's population, causing liver disease and cancer with prolonged infection. The narrow host range of the virus, being restricted largely to human hepatocytes, has made the development of relevant models to evaluate the efficacy of vaccines a challenge. We have developed a novel approach to accomplish this by generating a murine hepatoma cell line stably expressing nonstructural HCV antigens which can be used in vitro or in vivo to test HCV vaccine efficacies. These HCV-recombinant hepatoma cells formed large solid-mass tumours when implanted into syngeneic mice, allowing us to test candidate HCV vaccines to demonstrate the development of an HCV-specific immune response that limited tumour growth. Using this model, we tested the therapeutic potential of recombinant anti-HCV-specific vaccines based on two fundamentally different attenuated pathogen vaccine systems-attenuated Salmonella and recombinant adenoviral vector based vaccine. While attenuated Salmonella that secreted HCV antigens limited growth of the HCV-recombinant tumours when used in a therapeutic vaccination trial, replication-competent but noninfectious adenovirus expressing nonstructural HCV antigens showed overall greater survival and reduced weight loss compared to non-replicating nondisseminating adenovirus. Our results demonstrate a model with anti-tumour responses to HCV nonstructural (NS) protein antigens and suggest that recombinant vaccine vectors should be explored as a therapeutic strategy for controlling HCV and HCV-associated cancers.
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Antibody Delivery Mediated by Recombinant Adeno-associated Virus for the Treatment of Various Chronic and Infectious Diseases. Curr Gene Ther 2018; 16:363-374. [PMID: 28042779 DOI: 10.2174/1566523217666170102111251] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Revised: 12/13/2016] [Accepted: 12/22/2016] [Indexed: 11/22/2022]
Abstract
Monoclonal antibodies (mAbs) based-therapies are currently one of the most successful strategies to treat immune disorders, cancer and infectious diseases. Vectors derived from adenoassociated virus (AAV) are very attractive to deliver the genes coding the mAbs because they allow long-term expression thus, reducing the number of administrations. They can also penetrate biological barriers such as the blood-brain-barrier to transduce cells localized in immunoprivileged organs. Recent animal studies with AAV have demonstrated the capacity of AAV to deliver sufficient quantity of antibodies to confer an efficient immunoprotection against chronic and infectious diseases for several months to years. The treatment was successfully applied either for prophylaxis or therapeutic use, depending on the disease and its progression. In this review, we discuss the advantages and the limitations of AAV for mAb and immunoadhesin delivery. Recent advances in vector design and antibody engineering are also presented. Optimization of the vector design can improve the kinetic and the level of mAbs expression whereas protein engineering can enhance transgene product properties. Furthermore, an exhaustive review of pre-clinical studies for chronic diseases including Alzheimer disease, amyotrophic lateral sclerosis and cancer is presented as well as for infectious diseases.
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PO-0709: Postoperative salvage therapy for early recurrence in oral cavity squamous cell carcinoma. Radiother Oncol 2018. [DOI: 10.1016/s0167-8140(18)31019-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Gene Transfer of ZMapp Antibodies Mediated by Recombinant Adeno-Associated Virus Protects Against Ebola Infections. Hum Gene Ther 2018; 29:452-466. [PMID: 29179602 DOI: 10.1089/hum.2017.101] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Vectored delivery of the ZMapp antibody cocktail (c2G4, c4G7, and c13C6) by using recombinant adeno-associated viruses (rAAVs) could be useful for preventive immunization against Ebola virus infections because rAAVs can generate long-term antibody expression. Three rAAVs (serotype 9) encoding chimeric ZMapp antibodies were produced by triple-plasmid transfection up to 10 L-scale in WAVE bioreactors using HEK293 cells grown in suspension/serum-free conditions. Efficacy of AAV-c2G4 via intravenous (i.v.), intramuscular (i.m.), and intranasal (i.n.) routes of administration was evaluated in mice with two different doses of 2.7 × 1010 and 13.0 × 1010 vector genomes (vg). The best protective efficacies after Ebola challenge were obtained with the i.v. and i.m. routes. Serum concentrations of ZMapp antibodies positively correlated with survivability. Efficacy of the rAAV-ZMapp cocktail was then evaluated at a higher dose of 30.0 × 1010 vg. It conferred a more robust protection (90% i.v. and 60% i.m.) than rAAV-c4G7 (30%) and rAAV-c13C6 (70%), both administered separately at the same dose. Delivery of rAAV-c2G4 alone achieved up to 100% protection (100% i.v. and 90% i.m.) at the same dose. In conclusion, the preventive treatment was effective in mice. However, no advantage was observed for using the rAAV-ZMapp cocktail in comparison to the utilization of the single rAAV-c2G4.
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Abstract
Lentiviral vectors (LV) represent a key tool for gene and cell therapy applications. The production of these vectors in sufficient quantities for clinical applications remains a hurdle, prompting the field toward developing suspension processes that are conducive to large-scale production. This study describes a LV production strategy using a stable inducible producer cell line. The HEK293 cell line employed grows in suspension, thus offering direct scalability, and produces a green fluorescent protein (GFP)-expressing lentiviral vector in the 106 transduction units (TU)/mL range without optimization. The stable producer cell line, called clone 92, was derived by stable transfection from a packaging cell line with a plasmid encoding the transgene GFP. The packaging cell line expresses all the other necessary components to produce LV upon induction with cumate and doxycycline. First, the study demonstrated that LV production using clone 92 is scalable from 20 mL shake flasks to 3 L bioreactors. Next, two strategies were developed for high-yield LV production in perfusion mode using acoustic cell filter technology in 1–3 L bioreactors. The first approach uses a basal commercial medium and perfusion mode both pre- and post-induction for increasing cell density and LV recovery. The second approach makes use of a fortified medium formulation to achieve target cell density for induction in batch mode, followed by perfusion mode after induction. Using these perfusion-based strategies, the titer was improved to 3.2 × 107 TU/mL. As a result, cumulative functional LV titers were increased by up to 15-fold compared to batch mode, reaching a cumulative total yield of 8 × 1010 TU/L of bioreactor culture. This approach is easily amenable to large-scale production and commercial manufacturing.
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CARDIAC EFFECTS OF COMBINED SGLT 1/2 INHIBITION FOLLOWING EXPERIMENTAL MYOCARDIAL INFARCTION IN THE RAT. Can J Cardiol 2017. [DOI: 10.1016/j.cjca.2017.07.333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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EMPAGLIFLOZIN REDUCES LV MASS AND IMPROVES DIASTOLIC FUNCTION IN AN EXPERIMENTAL MODEL OF HEART FAILURE WITH PRESERVED EF. Can J Cardiol 2017. [DOI: 10.1016/j.cjca.2017.07.266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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Process intensification for high yield production of influenza H1N1 Gag virus-like particles using an inducible HEK-293 stable cell line. Vaccine 2017. [DOI: 10.1016/j.vaccine.2017.06.024] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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MORTALITY OF MOTHERS OF INFANTS BORN WITH NEONATAL ABSTINENCE SYNDROME: A POPULATION-BASED TWENTY YEAR COHORT STUDY. Paediatr Child Health 2017. [DOI: 10.1093/pch/pxx086.082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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43
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OC-022: Association of patient derived xenograft formation with oral cavity squamous cell cancer outcomes. Radiother Oncol 2017. [DOI: 10.1016/s0167-8140(17)30170-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Manufacturing of recombinant adeno-associated viruses using mammalian expression platforms. Biotechnol J 2017; 12. [DOI: 10.1002/biot.201600193] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Revised: 11/08/2016] [Accepted: 12/19/2016] [Indexed: 12/25/2022]
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Virus-Like Particles Derived from HIV-1 for Delivery of Nuclear Proteins: Improvement of Production and Activity by Protein Engineering. Mol Biotechnol 2016; 59:9-23. [PMID: 27830536 DOI: 10.1007/s12033-016-9987-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Virus-like particles (VLPs) derived from retroviruses and lentiviruses can be used to deliver recombinant proteins without the fear of causing insertional mutagenesis to the host cell genome. In this study we evaluate the potential of an inducible lentiviral vector packaging cell line for VLP production. The Gag gene from HIV-1 was fused to a gene encoding a selected protein and it was transfected into the packaging cells. Three proteins served as model: the green fluorescent protein and two transcription factors-the cumate transactivator (cTA) of the inducible CR5 promoter and the human Krüppel-like factor 4 (KLF4). The sizes of the VLPs were 120-150 nm in diameter and they were resistant to freeze/thaw cycles. Protein delivery by the VLPs reached up to 100% efficacy in human cells and was well tolerated. Gag-cTA triggered up to 1100-fold gene activation of the reporter gene in comparison to the negative control. Protein engineering was required to detect Gag-KLF4 activity. Thus, insertion of the VP16 transactivation domain increased the activity of the VLPs by eightfold. An additional 2.4-fold enhancement was obtained by inserting nuclear export signal. In conclusion, our platform produced VLPs capable of efficient protein transfer, and it was shown that protein engineering can be used to improve the activity of the delivered proteins as well as VLP production.
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P127 Neonatal and infant readmissions for late preterm and early term babies in Ontario and England: a cohort study using linked population-level healthcare data. Br J Soc Med 2016. [DOI: 10.1136/jech-2016-208064.224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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341. Nucleic Acid Delivery Using Vesicular Stomatitis Virus-Based Vesicles. Mol Ther 2016. [DOI: 10.1016/s1525-0016(16)33150-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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555. Development of a Post-Exposure Treatment for Ebola Virus Infections Based on AAV Vectors and Zmapp Antibody Cocktail. Mol Ther 2016. [DOI: 10.1016/s1525-0016(16)33363-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Abstract
We determined prescribing rates of neuraminidase inhibitors (NIs) for influenza in UK primary care since 2009 in relation to national prescribing guidelines. All NI prescriptions issued during the influenza seasons between October 2010 and May 2013 were extracted from The Health Improvement Network (THIN), a large UK primary-care database. We calculated NI prescribing rates per 100,000 person-weeks (pw) by age group, sex, deprivation level, influenza season and presence of chronic conditions with 95% confidence intervals (CIs), and used negative binomial regression models to determine the independent association between these variables and NI prescribing. NI prescribing was rare. The prescribing rate was 1·7/100,000 pw (95% CI 1·7-1·8) during influenza-active periods, and 0·1/100,000 (95% CI 0·1-0·1) during non-active periods. Prescribing rates were highest in 25- to 44-year-olds in 2010/2011 and in persons aged ⩾85 years in 2011/2012 and 2012/2013. Individuals with chronic conditions had significantly higher prescribing rates than persons without (rate ratio 2·62, 95% CI 2·27-3·03). GPs are more likely to prescribe NIs to high-risk individuals and during influenza active periods, as per national guidelines. We could not assess the proportion of patients with influenza-like illness who were prescribed an NI.
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Clinicopathological characteristics and cell cycle proteins as potential prognostic factors in myoepithelial carcinoma of salivary glands. Virchows Arch 2015; 468:305-12. [PMID: 26710792 DOI: 10.1007/s00428-015-1889-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Revised: 10/17/2015] [Accepted: 11/23/2015] [Indexed: 02/04/2023]
Abstract
Myoepithelial carcinoma (MCA) is a rare malignancy of salivary glands that was included in the WHO Classification of Head and Neck Tumors in 1991. MCA has shown a broad spectrum of clinical outcomes, but attempts to identify prognostic markers for this malignancy have not resulted in significant progress. Conventional histopathological characteristics such as tumour grade, nuclear atypia, mitotic index and cell proliferation have failed to predict the outcome of MCA. In this study, we reviewed the histopathology of 19 cases of MCA focusing on nuclear atypia, mitotic count, tumour necrosis, nerve and vascular invasion and occurrence of a pre-existing pleomorphic adenoma in connection to the MCA. Histopathological characteristics and clinical information were correlated with the immunohistochemical expression of cell cycle proteins including c-Myc, p21, Cdk4 and Cyclin D3. The proportion of tumour cells immunoreactive for these markers and their intensity of staining were correlated with clinical information using logistic regression, Kaplan-Meier and Cox regression. Using logistic regression analysis, cytoplasmic c-Myc expression was associated with the occurrence of metastases (P = 0.019), but limitations of semi-quantitation of immunostaining and the limited number of cases preclude definitive conclusions. Our data show that the occurrence of tumour necrosis predicts poor disease-free survival in MCA (P = 0.035).
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