Human Flt3L Generates Dendritic Cells from Canine Peripheral Blood Precursors: Implications for a Dog Glioma Clinical Trial

Glioblastoma multiforme (GBM) is the most common primary brain tumor in adults and carries a dismal prognosis. We have developed a conditional cytotoxic/immunotherapeutic approach using adenoviral vectors (Ads) encoding the immunostimulatory cytokine, human soluble fms-like tyrosine kinase 3 ligand (hsFlt3L) and the conditional cytotoxic molecule, i.e., Herpes Simplex Type 1- thymide kinase (TK). This therapy triggers an anti-tumor immune response that leads to tumor regression and anti-tumor immunological memory in intracranial rodent cancer models. We aim to test the efficacy of this immunotherapy in dogs bearing spontaneous GBM. In view of the controversy regarding the effect of human cytokines on dog immune cells, and considering that the efficacy of this treatment depends on hsFlt3L-stimulated dendritic cells (DCs), in the present work we tested the ability of Ad-encoded hsFlt3L to generate DCs from dog peripheral blood and compared its effects with canine IL-4 and GM-CSF.Our results demonstrate that hsFlT3L expressed form an Ad vector, generated DCs from peripheral blood cultures with very similar morphological and phenotypic characteristics to canine IL-4 and GM-CSF-cultured DCs. These include phagocytic activity and expression of CD11c, MHCII, CD80 and CD14. Maturation of DCs cultured under both conditions resulted in increased secretion of IL-6, TNF-alpha and IFN-gamma. Importantly, hsFlt3L-derived antigen presenting cells showed allostimulatory potential highlighting their ability to present antigen to T cells and elicit their proliferation.These results demonstrate that hsFlt3L induces the proliferation of canine DCs and support its use in upcoming clinical trials for canine GBM. Our data further support the translation of hsFlt3L to be used for dendritic cells' vaccination and gene therapeutic approaches from rodent models to canine patients and its future implementation in human clinical trials

Rotavirus NSP1 Inhibits NFκB Activation by Inducing Proteasome-Dependent Degradation of β-TrCP: A Novel Mechanism of IFN Antagonism

Mechanisms by which viruses counter innate host defense responses generally involve inhibition of one or more components of the interferon (IFN) system. Multiple steps in the induction and amplification of IFN signaling are targeted for inhibition by viral proteins, and many of the IFN antagonists have direct or indirect effects on activation of latent cytoplasmic transcription factors. Rotavirus nonstructural protein NSP1 blocks transcription of type I IFNα/β by inducing proteasome-dependent degradation of IFN-regulatory factors 3 (IRF3), IRF5, and IRF7. In this study, we show that rotavirus NSP1 also inhibits activation of NFκB and does so by a novel mechanism. Proteasome-mediated degradation of inhibitor of κB (IκBα) is required for NFκB activation. Phosphorylated IκBα is a substrate for polyubiquitination by a multisubunit E3 ubiquitin ligase complex, Skp1/Cul1/F-box, in which the F-box substrate recognition protein is β-transducin repeat containing protein (β-TrCP). The data presented show that phosphorylated IκBα is stable in rotavirus-infected cells because infection induces proteasome-dependent degradation of β-TrCP. NSP1 expressed in isolation in transiently transfected cells is sufficient to induce this effect. Targeted degradation of an F-box protein of an E3 ligase complex with a prominent role in modulation of innate immune signaling and cell proliferation pathways is a unique mechanism of IFN antagonism and defines a second strategy of immune evasion used by rotaviruses

Circulation of bovine respiratory syncytial virus in Brazil

1581863263

Revisões sistemáticas de antibioticoprofilaxia em cesarianas Systematic reviews of antibiotic prophylaxis in cesareans

O objetivo do trabalho foi analisar a evidência científica disponível sobre os efeitos da antibioticoprofilaxia em cesarianas. As presentes revisões sistemáticas compreenderam um exame detalhado da qualidade do desenho e da execução assim como da heterogeneidade clínica entre os ensaios. A meta-análise dos ensaios placebo-controlados (27 estudos) apontou eficácia aproximada de 65% para ambos os desfechos estudados, endometrite e infecção da ferida cirúrgica (IFC), correspondendo a uma queda da incidência de 11% e 5%, respectivamente. As análises de sensibilidade mostraram efeitos sumários semelhantes aos observados para o conjunto dos ensaios. O subgrupo dos 12 ensaios de cesáreas não eletivas indicou benefício importante da antibioticoprofilaxia para ambos os desfechos, correspondente a uma queda de 14% (endometrite) e 5% (IFC). Para cesáreas eletivas (dois ensaios), não foi mostrado benefício relevante. A evidência obtida dos ensaios comparativos de doses foi limitada devido a falhas metodológicas importantes e ao pequeno número de pacientes envolvidas (três ensaios). Os ensaios comparativos de antimicrobianos (sete estudos) não evidenciaram diferença de eficácia entre os dois esquemas analisados, cefalosporinas de 1ª e de 2ª geração.<br>This study reviews the available evidence on the efficacy of antibiotic prophylaxis in cesarean sections. The study included a detailed analysis of the quality of design and performance and the clinical heterogeneity of selected clinical trials. Meta-analysis of placebo-controlled trials estimated an efficacy of some 65% for the two study endpoints, endometritis and surgical wound infection, corresponding to a decrease in infection rates of some 11% and 5%, respectively. Sensitivity analyses showed summary effects similar to those observed for all studies. Results for the non-elective cesarean sections subgroup (12 studies) indicated a relevant benefit for both endpoints, corresponding to a decrease in incidence rates of some 14% (endometritis) and 5% (surgical infection wound). For elective surgeries (two trials), no relevant benefit was found. Evidence from comparative trials on number of doses was limited due to important methodological shortcomings and to the small number of patients enrolled (three trials). Comparative drug trials (seven studies) did not show evidence of different performance between first and second-generation cephalosporins