Epidemiology of low pathogenic avian influenza viruses in wild birds

Summary Although extensive data are available on low pathogenic avian influenza (LPAI) virus surveillance in wild birds in North America and Europe, data are scarce for other parts of the world, and our understanding of LPAI virus ecology in the natural reservoir is still far from complete. The outbreak of highly pathogenic avian influenza (HPAI) of the H5N1 subtype in the eastern hemisphere has put an increased focus on the role of wild birds in influenza virus transmission. Here, the authors review the current knowledge of the (molecular) epidemiology, genetics and evolution of LPAI viruses in wild birds, and identify some important gaps in current knowledge

Mycophenolate mofetil hampers antibody responses to a broad range of vaccinations in kidney transplant recipients:Results from a randomized controlled study

Objectives: To study the effect of mycophenolate mofetil (MMF) on various vaccination responses in kidney transplant recipients. Methods: In a randomized controlled trial (EudraCT nr.: 2014-001372-66), low immunologically risk kidney transplant recipients were randomized to TAC/MMF or TAC-monotherapy (TACmono), six months post-transplantation. One year after transplantation, in a pre-specified sub-study, recipients were vaccinated against pneumococcus, tetanus and influenza. Blood was sampled before and 21 days after vaccination. Adequate vaccination responses were defined by international criteria. A post-hoc analysis was conducted on SARS-CoV-2 vaccination responses within the same cohort. Results: Seventy-one recipients received pneumococcal and tetanus vaccines (TAC/MMF: n = 37, TACmono: n = 34), with 29 also vaccinated against influenza. When vaccinated, recipients were 60 (54–66) years old, with median eGFR of 54 (44–67) ml/min, tacrolimus trough levels 6.1 (5.4–7.0) ug/L in both groups and TAC/MMF daily MMF dose of 1000 (500–2000) mg. Adequate vaccination responses were: pneumococcal (TAC/MMF 43%, TACmono 74%, p = 0.016), tetanus (TAC/MMF 35%, TACmono 82%, p &lt; 0.0001) and influenza (TAC/MMF 20%, TACmono 71%, p = 0.0092). Only 7% of TAC/MMF responded adequately to all three compared to 36% of TACmono (p = 0.080). Additionally, 40% of TAC/MMF responded inadequately to all three, whereas all TACmono patients responded adequately to at least one vaccination (p = 0.041). Lower SARS-CoV-2 vaccination antibody responses correlated with lower pneumococcal antibody vaccination responses (correlation coefficient: 0.41, p = 0.040). Conclusions: MMF on top of tacrolimus severely hampers antibody responses to a broad range of vaccinations.</p

Mycophenolate mofetil hampers antibody responses to a broad range of vaccinations in kidney transplant recipients:Results from a randomized controlled study

Objectives: To study the effect of mycophenolate mofetil (MMF) on various vaccination responses in kidney transplant recipients. Methods: In a randomized controlled trial (EudraCT nr.: 2014-001372-66), low immunologically risk kidney transplant recipients were randomized to TAC/MMF or TAC-monotherapy (TACmono), six months post-transplantation. One year after transplantation, in a pre-specified sub-study, recipients were vaccinated against pneumococcus, tetanus and influenza. Blood was sampled before and 21 days after vaccination. Adequate vaccination responses were defined by international criteria. A post-hoc analysis was conducted on SARS-CoV-2 vaccination responses within the same cohort. Results: Seventy-one recipients received pneumococcal and tetanus vaccines (TAC/MMF: n = 37, TACmono: n = 34), with 29 also vaccinated against influenza. When vaccinated, recipients were 60 (54–66) years old, with median eGFR of 54 (44–67) ml/min, tacrolimus trough levels 6.1 (5.4–7.0) ug/L in both groups and TAC/MMF daily MMF dose of 1000 (500–2000) mg. Adequate vaccination responses were: pneumococcal (TAC/MMF 43%, TACmono 74%, p = 0.016), tetanus (TAC/MMF 35%, TACmono 82%, p &lt; 0.0001) and influenza (TAC/MMF 20%, TACmono 71%, p = 0.0092). Only 7% of TAC/MMF responded adequately to all three compared to 36% of TACmono (p = 0.080). Additionally, 40% of TAC/MMF responded inadequately to all three, whereas all TACmono patients responded adequately to at least one vaccination (p = 0.041). Lower SARS-CoV-2 vaccination antibody responses correlated with lower pneumococcal antibody vaccination responses (correlation coefficient: 0.41, p = 0.040). Conclusions: MMF on top of tacrolimus severely hampers antibody responses to a broad range of vaccinations.</p

Detection of influenza a viruses from different species by PCR amplification of conserved sequences in the matrix gene

The recently raised awareness of the threat of a new influenza pandemic has stimulated interest in the detection of influenza A viruses in human as well as animal secretions. Virus isolation alone is unsatisfactory for this purpose because of its inherent limited sensitivity and the lack of host cells that are universally permissive to all influenza A viruses. Previously described PCR methods are more sensitive but are targeted predominantly at virus strains currently circulating in humans, since the sequences of the primer sets display considerable numbers of mismatches to the sequences of animal influenza A viruses. Therefore, a new set of primers, based on highly conserved regions of the matrix gene, was designed for single-tube reverse transcription-PCR for the detection of influenza A viruses from multiple species. This PCR proved to be fully reactive with a panel of 25 genetically diverse virus isolates that were obtained from birds, humans, pigs, horses, and seals and that included all known subtypes of influenza A virus. It was not reactive with the 11 other RNA viruses tested. Comparative tests with throat swab samples from humans and fecal and cloacal swab samples from birds confirmed that the new PCR is faster and up to 100-fold more sensitive than classical virus isolation procedures.</p

Detection of influenza a viruses from different species by PCR amplification of conserved sequences in the matrix gene

The recently raised awareness of the threat of a new influenza pandemic has stimulated interest in the detection of influenza A viruses in human as well as animal secretions. Virus isolation alone is unsatisfactory for this purpose because of its inherent limited sensitivity and the lack of host cells that are universally permissive to all influenza A viruses. Previously described PCR methods are more sensitive but are targeted predominantly at virus strains currently circulating in humans, since the sequences of the primer sets display considerable numbers of mismatches to the sequences of animal influenza A viruses. Therefore, a new set of primers, based on highly conserved regions of the matrix gene, was designed for single-tube reverse transcription-PCR for the detection of influenza A viruses from multiple species. This PCR proved to be fully reactive with a panel of 25 genetically diverse virus isolates that were obtained from birds, humans, pigs, horses, and seals and that included all known subtypes of influenza A virus. It was not reactive with the 11 other RNA viruses tested. Comparative tests with throat swab samples from humans and fecal and cloacal swab samples from birds confirmed that the new PCR is faster and up to 100-fold more sensitive than classical virus isolation procedures.</p

Magnetic levitation stabilized by streaming fluid flows

We demonstrate that the ubiquitous laboratory magnetic stirrer provides a simple passive method of magnetic levitation, in which the so-called “flea” levitates indefinitely. We study the onset of levitation and quantify the flea’s motion (a combination of vertical oscillation, spinning and “waggling”), finding excellent agreement with a mechanical analytical model. The waggling motion drives recirculating flow, producing a centripetal reaction force that stabilized the flea. Our findings have implications for the locomotion of artificial swimmers and the development of bidirectional microfluidic pumps, and they provide an alternative to sophisticated commercial levitators

Immunometabolism pathways as the basis for innovative anti-viral strategies (INITIATE): a Marie Sklodowska-Curie innovative training network

The past century has witnessed major advances in the control of many infectious diseases, yet outbreaks and epidemics caused by (re-) emerging RNA viruses continue to pose a global threat to human health. As illustrated by the global COVID19 pandemic, high healthcare costs, economic disruption and loss of productivity reinforce the unmet medical need to develop new antiviral strategies to combat not only the current pandemic but also future viral outbreaks. Pivotal for effective anti-viral defense is the innate immune system, a first line host response that senses and responds to virus infection. While molecular details of the innate immune response are well characterized, this research field is now being revolutionized with the recognition that cell metabolism has a major impact on the antiviral and inflammatory responses to virus infections. A detailed understanding of the role of metabolic regulation with respect to antiviral and inflammatory responses, together with knowledge of the strategies used by viruses to exploit immunometabolic pathways, will ultimately change our understanding and treatment of pathogenic viral diseases. INITIATE is a Marie Sklodowska-Curie Actions Innovative Training Network (MSCA-ITN), with the goal to train 15 early stage PhD researchers (ESRs) to become experts in antiviral immunometabolism (https://initiate-itn.eu/). To this end, INITIATE brings together a highly complementary international team of academic and corporate leaders from 7 European countries, with outstanding track records in the historically distinct research fields of virology, immunology and metabolism. The ESRs of INITIATE are trained in these interdisciplinary research fields through individual investigator-driven research projects, specialized scientific training events, workshops on academia-industry interactions, outreach &amp; communication. INITIATE will deliver a new generation of creative and entrepreneurial researchers who will be able to face the inevitable future challenges in combating viral diseases

Contemporary human H3N2 influenza a viruses require a low threshold of suitable glycan receptors for efficient infection

Recent human H3N2 influenza A viruses (IAV) have evolved to employ elongated glycans terminating in α2,6-linked sialic acid as their receptors. These glycans are displayed in low abundancies by (humanized) Madin-Darby Canine Kidney cells (MDCK and hCK) which are commonly employed to propagate IAV, resulting in low or no viral propagation. Here, we examined whether the overexpression of the glycosyltransferases B3GNT2 and B4GALT1, which are responsible for the elongation of poly-N-acetyllactosamines (LacNAc), would result in improved A/H3N2 propagation. Stable overexpression of B3GNT2 and B4GALT1 in MDCK and hCK cells was achieved by lentiviral integration and subsequent antibiotic selection and confirmed by qPCR and protein mass spectrometry experiments. Flow cytometry and glycan mass spectrometry experiments using the B3GNT2 and/or B4GALT1 knock-in cells demonstrated increased binding of viral hemagglutinins and the presence of a larger number of LacNAc repeating units, especially on hCK-B3GNT2 cells. An increase in the number of glycan receptors did, however, not result in a greater infection efficiency of recent human H3N2 viruses. Based on these results, we propose that H3N2 IAVs require a low number of suitable glycan receptors to infect cells and that an increase in the glycan receptor display above this threshold does not result in improved infection efficiency

Evaluation of the Antiviral Response to Zanamivir Administered Intravenously for Treatment of Critically Ill Patients With Pandemic Influenza A (H1N1) Infection

A retrospective nationwide study on the use of intravenous (IV) zanamivir in patients receiving intensive care who were pretreated with oseltamivir in the Netherlands was performed. In 6 of 13 patients with a sustained reduction of the viral load, the median time to start IV zanamivir was 9 days (range, 4–11 days) compared with 14 days (range, 6–21 days) in 7 patients without viral load reduction (P = .052). Viral load response did not influence mortality. We conclude that IV zanamivir as late add-on therapy has limited effectiveness. The effect of an immediate start with IV zanamivir monotherapy or in combination with other drugs need to be evaluated

Two years after molecular diagnosis of familial hypercholesterolemia: Majority on cholesterol-lowering treatment but a minority reaches treatment goal

Background: The risk of premature cardiovascular disease in patients with familial hypercholesterolemia (FH) can be profoundly reduced by cholesterol-lowering therapy, and current guidelines for FH advocate ambitious low-density lipoprotein cholesterol (LDL-C) goals. In the present study, we determined whether these goals are reflected in current clinical practice once FH has been diagnosed. Methodology/Principal Findings: In 2008, we sent questionnaires to all subjects (aged 18-65 years) who were molecularly diagnosed with FH in the year 2006 through the screening program in the Netherlands. Of these 1062 subjects, 781 completed the questionnaire (46% males; mean age: 42±12 years; mean LDL-C at molecular diagnosis (baseline): 4.1±1.3 mmol/L). The number of persons that used cholesterol-lowering therapy increased from 397 (51%) at baseline to 636 (81%) after diagnosis. Mean treated LDL-C levels decreased significantly to 3.2±1.1 mmol/L two years after diagnosis. Only 22% achieved the LDL-C target level of ≤2.5 mmol/L. Conclusions/Significance: The proportion of patients using cholesterol-lowering medication was significantly increased after FH diagnosis through