The emergence of SARS-CoV-2 in 2019 and its rapid spread throughout the world has caused the largest pandemic of our modern era. The zoonotic origin of this pathogen highlights the importance of the ...One Health concept and the need for a coordinated response to this kind of threats. Since its emergence, the virus has caused >7 million deaths worldwide. However, the animal source for human outbreaks remains unknown. The ability of the virus to jump between hosts is facilitated by the presence of the virus receptor, the highly conserved angiotensin-converting enzyme 2 (ACE2), found in various mammals. Positivity for SARS-CoV-2 has been reported in various species, including domestic animals and livestock, but their potential role in bridging viral transmission to humans is still unknown. Additionally, the virus has evolved over the pandemic, resulting in variants with different impacts on human health. Therefore, suitable animal models are crucial to evaluate the susceptibility of different mammalian species to this pathogen and the adaptability of different variants. In this work, we established a transgenic mouse model that expresses the feline ACE2 protein receptor (cACE2) under the human cytokeratin 18 (K18) gene promoter's control, enabling high expression in epithelial cells, which the virus targets. Using this model, we assessed the susceptibility, pathogenicity, and transmission of SARS-CoV-2 variants. Our results show that the sole expression of the cACE2 receptor in these mice makes them susceptible to SARS-CoV-2 variants from the initial pandemic wave but does not enhance susceptibility to omicron variants. Furthermore, we demonstrated efficient contact transmission of SARS-CoV-2 between transgenic mice that express either the feline or the human ACE2 receptor.
The mosquito-borne West Nile virus (WNV) is a highly neurovirulent
currently representing an emergent zoonotic concern. WNV cycles in nature between mosquito vectors and birds that act as amplifier ...hosts and play an essential role in virus ecology, being, thus, WNV a threat to many species. Availability of an efficient avian vaccine would benefit certain avian populations, both birds grown for hunting and restocking activities, as well as endangered species in captive breeding projects, wildlife reservations, and recreation installations, and would be useful to prevent and contain outbreaks. Avian vaccination would be also of interest to limit WNV spillover to humans or horses from susceptible bird species that live in urbanized landscapes, like magpies. Herein, we have addressed the efficacy of a single dose of a WNV recombinant subviral particle (RSP) vaccine in susceptible magpie (
). The protective capacity of the RSP-based vaccine was demonstrated upon challenge of magpies with 5 × 10
plaque forming units of a neurovirulent WNV strain. A significant improvement in survival rates of immunized birds was recorded when compared to vehicle-inoculated animals (71.4 vs. 22.2%, respectively). Viremia, which is directly related to the capacity of a host to be competent for virus transmission, was reduced in vaccinated animals, as was the presence of infectious virus in feather follicles. Bird-to-bird transmission was recorded in three of six unchallenged (contact) magpies housed with non-vaccinated WNV-infected birds, but not in contact animals housed with vaccinated WNV-infected magpies. These results demonstrate the protective efficacy of the RSP-based vaccine in susceptible birds against WNV infection and its value in controlling the spread of the virus.
Introduction
Tofacitinib is an oral Janus kinase inhibitor for the treatment of psoriatic arthritis (PsA). We report the interim safety, tolerability, and efficacy of tofacitinib in PsA patients in ...OPAL Balance, a 3-year, open-label, long-term extension study (data cut-off: August 2017; database not locked, data may change).
Methods
Eligible patients from two phase (P) 3 (P3) tofacitinib PsA studies (OPAL Broaden, NCT01877668; OPAL Beyond, NCT01882439) entered OPAL Balance ≤ 3 months after completing the P3 study or discontinuing for reasons other than study-drug-related adverse events (AEs). Patients received open-label tofacitinib 5 mg twice daily (BID), with adjustments to 10 mg BID permitted post-month (M) 1. Certain concomitant conventional synthetic disease-modifying antirheumatic drugs were allowed. Primary endpoints were incidence/severity of AEs and laboratory abnormalities, and changes from baseline in laboratory parameters (reported up to M36 and M30, respectively). Efficacy (clinical/patient-reported outcomes) was reported through M30.
Results
A total of 686 patients were treated; at data cut-off, 68.2% remained in the study. Mean (range) treatment duration was 641 (1–1032) days; total treatment duration was 1153.2 patient-years. By M36, 79.6, 13.8, and 8.6% of patients reported AEs, serious AEs, and discontinuations due to AEs, respectively. Five deaths occurred; one within the risk period (incidence rate IR; patients with events/100 patient-years 0.1). IRs for AEs of special interest were: all (non-serious and serious) herpes zoster, 1.7; serious infections, 0.9; opportunistic infections, 0.3 (all disseminated/multi-dermatomal herpes zoster); malignancies excluding non-melanoma skin cancer (NMSC), 0.8; NMSC, 1.0; major adverse cardiovascular events, 0.3; pulmonary embolisms, 0.1; and arterial thromboembolisms, 0.4. No patients had deep vein thrombosis. Alanine aminotransferase and aspartate aminotransferase levels were elevated ≥ 3-fold the upper limit of normal in 4.0 and 2.2% of patients, respectively. Changes in laboratory parameters were generally stable over time, although lymphocyte counts decreased slightly. Efficacy was maintained through M30.
Conclusions
In this interim analysis of OPAL Balance, tofacitinib safety and efficacy in patients with PsA appeared to be consistent with those of the P3 studies. Efficacy was maintained over time.
Trial Registration
ClinicalTrials.gov identifier: NCT01976364.
Plain Language Summary
In many countries, tofacitinib is an approved medicine that can be used to treat psoriatic arthritis (PsA). In the study reported here (OPAL Balance), adult patients with PsA took tofacitinib for up to 3 years. We report a planned interim analysis, i.e., an analysis of information collected before the study finished. This early information suggests that the safety of tofacitinib, and how well it improved symptoms and quality of life (efficacy), was similar in this long study as in shorter studies. Information from the finished study will be reported later. OPAL Balance started on 17 February 2014. This interim analysis includes information collected by 31 August 2017. Before joining, patients had finished a 6-month or 12-month tofacitinib study (OPAL Broaden or OPAL Beyond). Patients in OPAL Balance took a 5 mg tofacitinib pill twice a day, but if PsA symptoms did not improve after 1 month, they could take a 10 mg pill twice a day. They could also take other medicines (including methotrexate or corticosteroids). Of the 686 patients who took tofacitinib, 546 (80%) experienced side effects over 3 years. These were considered serious for 95 patients (14%) and caused 59 patients (9%) to leave the study. Five patients died from causes not related to tofacitinib. Known tofacitinib side effects, including shingles (herpes zoster), serious infections (needing hospitalization), infections in patients with weakened immune systems, cancer, heart (cardiovascular) problems, and vein blockages (embolisms), were each reported by fewer than 20 patients. Most blood test results and tofacitinib efficacy were stable over 2.5 years.
In metazoans, the nuclear envelope (NE) breakdown (NEBD) occurs during “open” mitosis and meiosis. In the fission yeast Schizosaccharomyces pombe, the mitosis and the first meiotic division (MI) are ...“closed,” during which the NE is maintained. Intriguingly, during the second meiotic division (MII), the NE is also maintained, but nuclear and cytoplasmic molecules are mixed similarly to open mitosis, a phenomenon of unknown biological significance called “virtual” NEBD (vNEBD). Here, we show that importin-α-dependent nucleocytoplasmic transport regulates spindle disassembly late in anaphase B at MI, as previously reported for mitosis. At MII, however, spindle dissolution is triggered by vNEBD early in anaphase B, a mechanism that short-circuits the nucleocytoplasmic transport system. We demonstrate that the sequential action of these two spindle disassembly systems regulates the spatiotemporal order and ploidy of the meiotic products.
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•Imp1-dependent transport drives spindle dissolution in S. pombe meiosis I•vNEBD short-circuits the Imp1-dependent disassembly, shortening maximum spindle length•Imp1-dependent and vNEBD spindle disassembly systems are distinct but exchangeable•Sequential Imp1- and vNEBD-driven spindle disassembly controls spore order and ploidy
vNEBD is a phenomenon described in the fission yeast second meiotic division (MII), which resembles the nuclear envelope breakdown that characterizes the mitotic phase in eukaryotes. Flor-Parra et al. describe a biological role of vNEBD in spindle disassembly.
West Nile virus (WNV) is a re-emergent mosquito-borne RNA virus that causes major outbreaks of encephalitis around the world. However, there is no therapeutic treatment to struggle against WNV, and ...the current treatment relies on alleviating symptoms. Therefore, due to the threat virus poses to animal and human health, there is an urgent need to come up with fast strategies to identify and assess effective antiviral compounds. A relevant target when developing drugs against RNA viruses is the viral RNA-dependent RNA polymerase (RdRp), responsible for the replication of the viral genome within a host cell. RdRps are key therapeutic targets based on their specificity for RNA and their essential role in the propagation of the infection. We have developed a fluorescence-based method to measure WNV RdRp activity in a fast and reliable real-time way. Interestingly, rilpivirine has shown in our assay inhibition of the WNV RdRp activity with an IC50 value of 3.3 μM and its antiviral activity was confirmed in cell cultures. Furthermore, this method has been extended to build up a high-throughput screening platform to identify WNV polymerase inhibitors. By screening a small chemical library, novel RdRp inhibitors 1–4 have been identified. When their antiviral activity was tested against WNV in cell culture, 4 exhibited an EC50 value of 2.5 μM and a selective index of 12.3. Thus, rilpivirine shows up as an interesting candidate for repurposing against flavivirus. Moreover, the here reported method allows the rapid identification of new WNV RdRp inhibitors.
•A fluorescence-based method that accurately measure the WNV NS5 polymerization activity in real time is here reported.•Rilpivirine strongly inhibits the polymerization activity of WNV NS5 RdRp in vitro.•This fluorescence-based method has been used as a screening platform to find novel non-nucleoside WNV NS5 inhibitors.•Both rilpivirine and the here identified WNV NS5 Pol inhibitors show anti-WNV activity in cell culture.
Still’s disease, the paradigm of autoinflammation-cum-autoimmunity, predisposes for a cytokine storm with excessive T lymphocyte activation upon viral infection. Loss of function of the purine ...nucleoside enzyme FAMIN is the sole known cause for monogenic Still’s disease. Here we discovered that a FAMIN-enabled purine metabolon in dendritic cells (DCs) restrains CD4+ and CD8+ T cell priming. DCs with absent FAMIN activity prime for enhanced antigen-specific cytotoxicity, IFNγ secretion, and T cell expansion, resulting in excessive influenza A virus-specific responses. Enhanced priming is already manifest with hypomorphic FAMIN-I254V, for which ∼6% of mankind is homozygous. FAMIN controls membrane trafficking and restrains antigen presentation in an NADH/NAD+-dependent manner by balancing flux through adenine-guanine nucleotide interconversion cycles. FAMIN additionally converts hypoxanthine into inosine, which DCs release to dampen T cell activation. Compromised FAMIN consequently enhances immunosurveillance of syngeneic tumors. FAMIN is a biochemical checkpoint that protects against excessive antiviral T cell responses, autoimmunity, and autoinflammation.
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•A FAMIN-enabled purine metabolon in dendritic cells restrains T cell priming•FAMIN prevents cytoplasmic NADH/NAD+ reductive stress that enhances priming•Inosine generated from hypoxanthine by FAMIN inhibits T cell priming•FAMIN ameliorates immunopathology in influenza but dampens tumor surveillance
Saveljeva et al. identify a biochemical mechanism in dendritic cells that restrains T cell priming and prevents immunopathology but dampens tumor surveillance. FAMIN enables a purine nucleotide cycle, which prevents cytoplasmic NADH/NAD+ reductive stress that augments antigen presentation, and it generates inosine, which inhibits T cell activation.
Research priorities in Antimicrobial Stewardship (AMS) have rapidly evolved in the last decade. The need for a more efficient use of antimicrobials have fueled plenty of studies to define the optimal ...duration for antibiotic treatments, and yet, there still are large areas of uncertainty in common clinical scenarios. Pseudomonas aeruginosa has been pointed as a priority for clinical research, but it has been unattended by most randomized trials tackling the effectiveness of short treatments. The study protocol of the SHORTEN-2 trial is presented as a practical example of new ways to approach common obstacles for clinical research in AMS.
To determine whether a 7-day course of antibiotics is superior to 14-day schemes for treating bloodstream infections by P. aeruginosa (BSI-PA).
A superiority, open-label, randomized controlled trial will be performed across 30 Spanish hospitals. Adult patients with uncomplicated BSI-PA will be randomized to receive a 7 versus 14-day course of any active antibiotic. The primary endpoint will be the probability for the 7-day group of achieving better outcomes than the control group, assessing altogether clinical effectiveness, severe adverse events, and antibiotic exposure through a DOOR/RADAR analysis. Main secondary endpoints include treatment failure, BSI-PA relapses, and mortality. A superiority design was set for the primary endpoint and non-inferiority for treatment failure, resulting in a sample size of 304 patients.
SHORTEN-2 trial aligns with some of the priorities for clinical research in AMS. The implementation of several methodological innovations allowed overcoming common obstacles, like feasible sample sizes or measuring the clinical impact and unintended effects.
EudraCt: 2021-003847-10; ClinicalTrials.gov: NCT05210439.
Flaviviruses are (re)-emerging RNA viruses strictly dependent on lipid metabolism for infection. In the search for host targeting antivirals, we explored the effect of pharmacological modulation of ...fatty acid metabolism during flavivirus infection. Considering the central role of acetyl-Coenzyme A carboxylase (ACC) on fatty acid metabolism, we analyzed the effect of three small-molecule ACC inhibitors (PF-05175157, PF-05206574, and PF-06256254) on the infection of medically relevant flaviviruses, namely West Nile virus (WNV), dengue virus, and Zika virus. Treatment with these compounds inhibited the multiplication of the three viruses in cultured cells. PF-05175157 induced a reduction of the viral load in serum and kidney in WNV-infected mice, unveiling its therapeutic potential for the treatment of chronic kidney disease associated with persistent WNV infection. This study constitutes a proof of concept of the reliability of ACC inhibitors to become viable antiviral candidates. These results support the repositioning of metabolic inhibitors as broad-spectrum antivirals.
Usutu virus (USUV) is an African mosquito-borne flavivirus closely related to West Nile virus and Japanese encephalitis virus, which host range includes mainly mosquitoes and birds, although ...infections in humans have been also documented, thus warning about USUV as a potential health threat. Circulation of USUV in Africa was documented more than 50 years ago, but it was not until the last decade that it emerged in Europe causing episodes of avian mortality and some human severe cases. Since autophagy is a cellular pathway that can play important roles on different aspects of viral infections and pathogenesis, the possible implication of this pathway in USUV infection has been examined using Vero cells and two viral strains of different origin. USUV infection induced the unfolded protein response, revealed by the splicing of Xbp-1 mRNA. Infection with USUV also stimulated the autophagic process, which was demonstrated by an increase in the cytoplasmic aggregation of microtubule-associated protein 1 light chain 3 (LC3), a marker of autophagosome formation. In addition to this, an increase in the lipidated form of LC3, that is associated with autophagosome formation, was noticed following infection. Pharmacological modulation of the autophagic pathway with the inductor of autophagy rapamycin resulted in an increase in virus yield. On the other hand, treatment with 3-methyladenine or wortmannin, two distinct inhibitors of phosphatidylinositol 3-kinases involved in autophagy, resulted in a decrease in virus yield. These results indicate that USUV virus infection upregulates the cellular autophagic pathway and that drugs that target this pathway can modulate the infection of this virus, thus identifying a potential druggable pathway in USUV-infection.
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