27 research outputs found
Politique indienne et liberté religieuse au Canada, 1870-1950 : l’exemple des cimetières de bande
Depuis le 18e siècle, les autorités politiques canadiennes ont privilégié une approche de tolérance envers la diversité culturelle et religieuse, bien qu’à première vue, la politique indienne, et plus particulièrement les dispositions de la Loi sur les Indiens qui rendaient illégales certaines pratiques culturelles et religieuses, semblait s’inscrire en faux par rapport à cette orientation. Or, une analyse de l’attitude des fonctionnaires des Affaires indiennes en lien avec la gestion des cimetières de bande, entre 1870 et 1950, tend à confirmer que le contrôle des dépenses liées à la mise en application de la politique indienne et le souci d’assurer le succès des efforts de colonisation intérieure primaient sur la volonté d’acculturer et d’émanciper les Indiens, et de brimer par conséquent leur liberté religieuse.Abstract: Since the 18th century, Canadian political authorities have generally tended to embrace a tolerant approach regarding cultural and religious diversity. Yet, policies expressed in the Indian Act provisions prohibiting certain cultural and religious practices would seem to contradict this avowed orientation. Indeed, an analysis of past attitudes of Indian Affairs officials in connection with the management of band cemeteries between 1870 and 1950, sustains this impression. It would appear that the exercise of controls on expenses relating to the implementation of a First Nations’ policy, as well as concerns regarding the success of internal colonization initiatives, took precedence over a desire to acculturate and emancipate indigenous populations. In the final analysis, they in fact operated to impair their religious freedom
Characteristics of rVSV-ZEBOV production kinetics in HEK293 and Vero cells
The vesicular stomatitis virus (VSV) can be used as an effective vaccine platform, inducing both cellular and humoral immunity. Because VSV infections of humans are mostly asymptomatic, recombinant VSV (rVSV) can be used as a platform to safely deliver and express foreign antigens. This research study focusses on cell culture production of an rVSV expressing the Ebola virus glycoprotein on its surface (rVSV-ZEBOV). This virus has been demonstrated to be safe to administer to humans. In addition, recent results of a human phase III clinical trial showed that this vaccine can efficiently protect against Ebola virus infection. However, limited data is available in the literature about the growth characteristics of this virus during the production process. In our study, we investigated the influence of multiplicity of infection (MOI), time of infection (TOI), time of harvest (TOH), media components and temperature on the viral titer (TCID50/mL, ddPCR) of rVSV-ZEBOV produced from cell culture. Results are compared between the standard production in the Vero cell line and in a suspension-adapted HEK293-based cell line without serum
IL28B SNP screening and distribution in the French Canadian population using a rapid PCR-based test
Single nucleotide polymorphisms (SNPs) in the proximity of the interleukin-28B (IL28B) gene can predict spontaneous resolution of hepatitis C virus (HCV) infection and response to interferon therapy. Screening for this polymorphism has become part of the standard criteria for the management of HCV-infected patients, hence the need for a rapid, cost-effective screening method. Here, we describe a rapid PCR-based test to screen for two IL28B SNPs (rs12979860 and rs8099917). We used this test to investigate IL28B polymorphism and prevalence in a cohort of French Canadian injection drug users who are part of a unique population known to have a strong genetic founder effect. This population had lower linkage disequilibrium between the two tested SNPs as compared to other cohorts (|d′| = 0.68, r = 0.59). The special genetic makeup should be considered in the management of HCV-infected patients within that population
Production of rVSV-ZEBOV in serum-free suspension culture of HEK 293SF cells.
Abstract Ebola virus disease is an urgent international priority. Promising results for several vaccine candidates have been reported in non-human primate studies and clinical trials with the most promising being the rVSV-ZEBOV vaccine. In this study, we sought to produce rVSV-ZEBOV in HEK 293SF cells in suspension and serum-free media. The purpose of this study was to establish a process using the HEK 293SF production platform, optimise the production titre, demonstrate scalability and the efficiency of the generated material to elicit an immune reaction in an animal model. Critical process parameters were evaluated to maximize production yield and process robustness and the following operating conditions: 1–2 × 106 cells/mL grown in HyClone HyCell TransFx-H media infected at an MOI of 0.001 with a temperature shift to 34 °C during the production phase and a harvest of the product after 48 h. Using these conditions, scalability in a 3.5 L controlled bioreactor was shown reaching a titre of 1.19 × 108 TCID50/mL at the peak of production, the equivalent of 4165 doses of vaccine per litre. The produced virus was shown to be thermostable in the culture media and, when concentrated, purified and administered to mice, demonstrated the ability to induce a ZEBOV-specific immune response
Evaluation of novel HIV vaccine candidates using recombinant vesicular stomatitis virus vector produced in serum-free Vero cell cultures.
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
IL28B SNP screening and distribution in the French Canadian population using a rapid PCR-based test
Optimisation de l'opération d'une centrale de production d'eau refroidie à l'aide des algorithmes
Role of double-stranded RNA binding proteins, TRBP, ADAR1 and PACT, on PKR activation and HIV-1 production
The interferon-induced protein kinase RNA-activated (PKR) is activated after virus infection but not during human immunodeficiency virus type-1 (HIV-1) infection of lymphocytes. The TAR RNA binding protein (TRBP) counteracts the inhibitory effects of PKR on HIV-1 expression and replication. In U251MG astrocytes, which are low TRBP producers, PKR is activated upon HIV-1 transfection and viral production is low. Astrocytes overexpressing TRBP express more viral proteins. Expression of adenosine deaminase acting on RNA-1 (ADAR1)-p150 and its binding to PKR are increased during high HIV-1 replication. ADAR1 also reverses PKR inhibition of HIV-1 expression and production in HEK 293T and astrocytes. DNA- and RNA-binding domains of ADAR1 are required for PKR inhibition. Surprisingly, the PKR activator protein (PACT) also reversed PKR inhibition of HIV-1 expression in HEK 293T. These results indicate that three double stranded RNA binding proteins, TRBP, ADAR1 and PACT belong to a multiprotein complex that inhibits PKR function during HIV-1 infection.La protéine kinase induite par l'interféron activée par l'ARN (PKR) est activée après une infection virale, mais pas durant l'infection des lymphocytes par le Virus de l'Immunodéficience Humaine de type-1 (VIH-1). La protéine de liaison à l'ARN TAR (TRBP) empêche l'effet inhibiteur de PKR sur l'expression et la réplication du VIH-1. Dans les astrocytes U251MG, exprimant faiblement TRBP, PKR est activée par le VIH-1 et la production virale reste basse. Des astrocytes qui surexpriment TRBP produisent plus de protéines virales. L'expression de l'adénosine déaminase agissant sur l'ARN-1 (ADAR1)-p150 et sa liaison à PKR augmentent quand le VIH-1 se réplique activement. ADAR1 inverse l'inhibition de l'expression et de la production du VIH-1 par PKR. L'inhibition de PKR nécessite les domaines de liaison à l'ARN et à l'ADN d'ADAR1. Étonnamment, l'activateur de PKR (PACT) inverse aussi l'inhibition du VIH-1 par PKR dans les HEK 293T. Ces résultats indiquent que trois protéines liant l'ARN double brin, TRBP, ADAR1 et PACT forment un complexe multiprotéique qui inhibe la fonction de PKR pendant l'infection du VIH-1