Upstream process intensification using Viral Sensitizer technology

Upstream process intensification technologies will play an increasingly important role to cater to growing global demands in vaccines and other viroceuticals including gene therapy vectors and oncolytic viruses. We have discovered and developed viral sensitizer technology, a collection of compounds that improve virus growth with potential utility in a multitude of applications, including manufacturing. We have found that viral sensitizer formulations enhance viral production to varying extents depending on the virus and manufacturing substrate. Productivity can be improved substantially in commonly used production cell lines. In cell culture applications, viral sensitizers can be combined with other process intensification technologies including fixed bed macrocarrier-based bioreactors, as well as commercially available serum-free media and growth supplements. To support commercial implementation, we have developed analytical tools to track compounds during production

Modulators and effectors of inositol hexakisphosphate activity in prostate cancer cells : from clinical prognosis to enhanced therapeutics

Thèse numérisée par la Division de la gestion de documents et des archives de l'Université de Montréal

Exploiting tumor epigenetics to improve oncolytic virotherapy

Oncolytic viruses (OVs) comprise a versatile and multi-mechanistic therapeutic platform in the growing arsenal of anticancer biologics. These replicating therapeutics find favorable conditions in the tumor niche, characterized among others by increased metabolism, reduced anti-tumor/antiviral immunity, and disorganized vasculature. Through a self-amplification that is dependent on multiple cancer-specific defects, these agents exhibit remarkable tumor selectivity. With several OVs completing or entering Phase III clinical evaluation, their therapeutic potential as well as the challenges ahead are increasingly clear. One key hurdle is tumor heterogeneity, which results in variations in the ability of tumors to support productive infection by OVs and to induce adaptive anti-tumor immunity. To this end, mounting evidence suggests tumor epigenetics may play a key role. This review will focus on the epigenetic landscape of tumors and how it relates to OV infection. Therapeutic strategies aiming to exploit the epigenetic identity of tumors in order to improve OV therapy are also discussed

Rendements et pratiques des cultures maraîchères en agriculture biologique au Sénégal

Les rendements en agriculture biologique font l'objet de controverses et sont considérés comme plus faibles qu'en agriculture conventionnelle. En Afrique, l'agriculture biologique recouvre une grande diversité de pratiques et les rendements présentent de fortes incertitudes. Les analyses des rendements et des itinéraires techniques en agriculture biologique sont présentées pour trois cultures maraîchères au Sénégal. Les résultats sont ensuite comparés aux rendements usuels de l'agriculture conventionnelle. Deux types de données sont utilisés, provenant de parcelles d'agriculteurs : i) suivi de champs conduits selon des itinéraires techniques d'agriculture biologique vs. itinéraires techniques conventionnels ; ii) résultats issus des actions de l'organisation non gouvernementale ENDA-PRONAT, suivant un cahier des charges copié sur celui de l'agriculture biologique. Les suivis comparatifs de parcelles de chou pommé et de tomate en saison des pluies mettent en évidence des ratios de rendement agriculture biologique/conventionnelle de 74 et 40 % respectivement. Ces valeurs confirment la tendance générale des résultats de la littérature. Elles sont expliquées par une fertilisation azotée plus faible et l'absence de mesures de protection efficace contre les maladies et ravageurs des cultures. Les rendements en oignon des parcelles d'agriculture biologique chez les producteurs sont très variables : en moyenne de 19,4 t/ha à 11,0 t/ha suivant les années dans la zone des Niayes, 21,0 t/ha dans le Bassin arachidier et seulement 8,6 t/ha dans la vallée du fleuve Sénégal. Les rendements de la culture d'oignon au Sénégal observés dans la littérature varient aussi dans de grandes proportions, de 10,7 à 32 t/ha. Dans certains cas, les rendements en agriculture biologique sont supérieurs à ceux des itinéraires techniques de l'agriculture conventionnelle. Ce constat, déjà observé dans la littérature scientifique, montre que l'agriculture biologique est une voie de développement de l'agriculture à ne pas écarter en Afrique

Overcoming barriers in viral vector manufacturing: Small molecule targeting of antiviral defences

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Ring-opening metathesis polymerization of cyclooctene derivatives with chain transfer agents derived from glycerol carbonate

International audienceThe synthesis of a variety of mono- and di-(glycerol carbonate) telechelic polyolefins has been achieved upon ruthenium-catalyzed ring-opening metathesis polymerization (ROMP) of cyclooctene (COE) derivatives in the presence of a vinyl or acryloyl derivative of glycerol carbonate (GC) acting as a chain-transfer agent (CTA). Reaction monitoring based on SEC and 1H NMR analyses suggested that the ROMP proceeds through the formation of first the α-GC,ω-vinyl-poly(cyclooctene) (PCOE) intermediate, which eventually evolves over time into the α,ω-di(GC)-PCOE. The nature of the solvent was shown to have a significant impact on both the reaction rates and the eventual selectivity for the mono-/di-telechelic PCOE. ROMP of 3-alkyl (methyl, ethyl, n-hexyl)-substituted COEs (3-R-COEs) afforded only the α-GC,ω-vinyl-poly(3-R-COE)s, as a result of the steric hindrance around the active intermediate, while a 5-ethyl substituted COE (5-Et-COE) enabled access to the corresponding α,ω-di(GC)-poly(5-Et-COE). The ROMP of 5,6-epoxy-, 5-hydroxy- and 5-oxo-functionalized COEs in the presence of acryloyl-GC as the CTA has also been achieved, affording from the first two monomers polymers with GC end-groups at both extremities, while a 60 : 40 mixture of mono- and di-GC terminated P(5-O[double bond, length as m-dash]COE) was observed in the latter case

α,ω-Di(glycerol carbonate) telechelic polyesters and polyolefins as precursors to polyhydroxyurethanes: an isocyanate-free approach

International audienceα,ω-Di(glycerol carbonate) telechelic poly(propylene glycol) (PPG), poly(ethylene glycol) (PEG), poly(ester ether) (PEE), and poly(butadiene) (PBD) have been synthesized through chemical modification of the corresponding α,ω-dihydroxy telechelic polymers (PPG-OH2, PEG-OH2, PEE-OH2 and PBD-OH2, respectively). Tosylation of the polymer diols with 4-tosylmethyl-1,3-dioxolan-2-one (GC-OTs) afforded, in high yields, the desired PPG, PEG, PEE and PBD end-capped at both termini with a five-membered ring cyclic glycerol carbonate (4-hydroxymethyl-1,3-dioxolan-2-one, GC). The GC-functionalization of the polymers at both chain-ends has been confirmed by NMR (1H, 13C, 1D and 2D) and FTIR spectroscopies. Using PPG-GC2 to demonstrate the concept, the corresponding polyhydroxyurethanes (PHUs/non-isocyanate polyurethanes (NIPUs)) have been subsequently prepared following a non-isocyanate method upon ring-opening catalyst-free polyaddition of the PPG-GC2 with JEFFAMINEs (Mn = 230-2000 g mol−1). The effect of various additives introduced during the polyaddition reaction has been studied at different temperatures. In particular, addition of LiBr (5 mol%) to the reaction medium was found to slightly promote the cyclocarbonate/amine reaction. The polymerization process was supported by FTIR and SEC analyses

Influence of pH on the Cytotoxic Activity of Inositol Hexakisphosphate (IP6) in Prostate Cancer

Objectives: In the present study, we investigated whether the pH of IP6 could influence its anti-tumoral activity in vitro. Methods: PC-3 cells were exposed to IP6 at pH 5, pH 7, and pH 12 and we evaluated the metabolic activity (WST-1 assay), cell proliferation (cell count), cell cycle distribution (FACS), and mitochondrial depolarization (JC-1 staining) in vitro. Results: Our results demonstrated that IP6 at pH 5 and pH 12 were more potent at lowering the metabolic activity of PC-3 cells than IP6 at pH 7. Treatment with IP6 at pH 12 also caused the greatest inhibition in cellular proliferation and accumulation of PC-3 cells in sub-G1. Finally, IP6 at pH 12 lead to a reduction in phospho-AKT and phospho-PDK1 and upregulated phospho-ERK. Conclusion: Together, our data strongly suggest that the pH of IP6 effectively modulates its anti-tumoral activity and should be reported in future studies

Intermittent preventive treatment of malaria provides substantial protection against malaria in children already protected by an insecticide-treated bednet in Burkina Faso: a randomised, double-blind, placebo-controlled trial.

BACKGROUND: Intermittent preventive treatment of malaria in children (IPTc) is a promising new approach to the control of malaria in areas of seasonal malaria transmission but it is not known if IPTc adds to the protection provided by an insecticide-treated net (ITN). METHODS AND FINDINGS: An individually randomised, double-blind, placebo-controlled trial of seasonal IPTc was conducted in Burkina Faso in children aged 3 to 59 months who were provided with a long-lasting insecticide-treated bednet (LLIN). Three rounds of treatment with sulphadoxine pyrimethamine plus amodiaquine or placebos were given at monthly intervals during the malaria transmission season. Passive surveillance for malaria episodes was established, a cross-sectional survey was conducted at the end of the malaria transmission season, and use of ITNs was monitored during the intervention period. Incidence rates of malaria were compared using a Cox regression model and generalized linear models were fitted to examine the effect of IPTc on the prevalence of malaria infection, anaemia, and on anthropometric indicators. 3,052 children were screened and 3,014 were enrolled in the trial; 1,505 in the control arm and 1,509 in the intervention arm. Similar proportions of children in the two treatment arms were reported to sleep under an LLIN during the intervention period (93%). The incidence of malaria, defined as fever or history of fever with parasitaemia ≥ 5,000/µl, was 2.88 (95% confidence interval [CI] 2.70-3.06) per child during the intervention period in the control arm versus 0.87 (95% CI 0.78-0.97) in the intervention arm, a protective efficacy (PE) of 70% (95% CI 66%-74%) (p<0.001). There was a 69% (95% CI 6%-90%) reduction in incidence of severe malaria (p = 0.04) and a 46% (95% CI 7%-69%) (p = 0.03) reduction in the incidence of all-cause hospital admissions. IPTc reduced the prevalence of malaria infection at the end of the malaria transmission season by 73% (95% CI 68%-77%) (p<0.001) and that of moderately severe anaemia by 56% (95% CI 36%-70%) (p<0.001). IPTc reduced the risks of wasting (risk ratio [RR] = 0.79; 95% CI 0.65-1.00) (p = 0.05) and of being underweight (RR = 0.84; 95% CI 0.72-0.99) (p = 0.03). Children who received IPTc were 2.8 (95% CI 2.3-3.5) (p<0.001) times more likely to vomit than children who received placebo but no drug-related serious adverse event was recorded. CONCLUSIONS: IPT of malaria provides substantial protection against malaria in children who sleep under an ITN. There is now strong evidence to support the integration of IPTc into malaria control strategies in areas of seasonal malaria transmission. TRIAL REGISTRATION: ClinicalTrials.govNCT00738946. Please see later in the article for the Editors' Summary

Syngeneic mouse model of human HER2+ metastatic breast cancer for the evaluation of trastuzumab emtansine combined with oncolytic rhabdovirus

BackgroundEstablished mouse models of HER2+ cancer are based on the over-expression of rodent Neu/Erbb2 homologues, which are incompatible with human HER2 (huHER2) targeted therapeutics. Additionally, the use of immune-deficient xenograft or transgenic models precludes assessment of native anti-tumour immune responses. These hurdles have been a challenge for our understanding of the immune mechanisms behind huHER2-targeting immunotherapies.MethodsTo assess the immune impacts of our huHER2-targeted combination strategy, we generated a syngeneic mouse model of huHER2+ breast cancer, using a truncated form of huHER2, HER2T. Following validation of this model, we next treated tumour-bearing with our immunotherapy strategy: oncolytic vesicular stomatitis virus (VSVΔ51) with clinically approved antibody-drug conjugate targeting huHER2, trastuzumab emtansine (T-DM1). We assessed efficacy through tumour control, survival, and immune analyses.ResultsThe generated truncated HER2T construct was non-immunogenic in wildtype BALB/c mice upon expression in murine mammary carcinoma 4T1.2 cells. Treatment of 4T1.2-HER2T tumours with VSVΔ51+T-DM1 yielded robust curative efficacy compared to controls, and broad immunologic memory. Interrogation of anti-tumour immunity revealed tumour infiltration by CD4+ T cells, and activation of B, NK, and dendritic cell responses, as well as tumour-reactive serum IgG.ConclusionsThe 4T1.2-HER2T model was used to evaluate the anti-tumour immune responses following our complex pharmacoviral treatment strategy. These data demonstrate utility of the syngeneic HER2T model for assessment of huHER2-targeted therapies in an immune-competent in vivo setting. We further demonstrated that HER2T can be implemented in multiple other syngeneic tumour models, including but not limited to colorectal and ovarian models. These data also suggest that the HER2T platform may be used to assess a range of surface-HER2T targeting approaches, such as CAR-T, T-cell engagers, antibodies, or even retargeted oncolytic viruses