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Background Untreated hepatitis C virus (HCV) infection can lead to liver disease, cancer and premature death; HIV coinfection can accelerate adverse outcomes. People living with HIV (PLWH) should be screened for HCV with an antibody test at least once and more frequently if other risk factors. A diagnostic HCV RNA test should be used to determine cure/clearance (RNA-negative) vs active infection (RNA-positive). Among people with HCV/HIV coinfection in New York City (NYC), we aimed to 1) describe HCV testing, cure/clearance, reinfection and identify disparities; 2) assess relative timing of HCV/HIV coinfection diagnosis to evaluate HCV testing among PLWH. Methods PLWH as of September 30, 2021 were matched to people with a positive HCV test July 1, 2014–December 31, 2020; HCV test results through December 31, 2021 were used for analyses and to observe cure. A HCV clearance cascade was created to evaluate testing, cure/clearance and reinfection, and was stratified by age, sex and race/ethnicity. Timing of coinfection was assessed for people with new HCV/HIV diagnoses January 1, 2014–December 31, 2020 to identify recent trends. Coinfection date was defined as the later HCV or HIV diagnosis date. Results There were 11,137 PLWH with any positive HCV test. Of these, 10,773 (97%) had an RNA test; 8,926 (83%) had initial active infection; 6,901 (77%) had cure/clearance and 302 (4%) with cure/clearance were reinfected (Figure 1). Black Non-Hispanic (NH) people and those aged 20–39 had a high burden of active infection, with 3,653 (87%) and 803 (93%), respectively. Both groups had proportionally lower cure/clearance (77% and 63%, respectively) compared to Asian NH people (86%) and people ≥ 60 (81%) having the highest proportions. Most people with recent coinfections were diagnosed with HIV prior to HCV (annual range: 39%–71%) (Figure 2). Conclusion HCV diagnostic testing and cure/clearance were high and reinfection was low among people with coinfection in NYC. Most people with coinfection had HCV RNA tests, indicating appropriate HCV testing in this population. Cure/clearance could be improved among younger and Black NH people; provider and patient education might improve outcomes. To initiate timely treatment, providers should continue screening PLWH for HCV as HIV infection often precedes HCV infection. Disclosures All Authors: No reported disclosures.

Poultry passport to pandemic What conditions are required to nurture the seeds of a pandemic? The avian influenza virus H7N9 rarely spills over into humans, but when it does, mortality exceeds 30%, far in excess of that of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Chen et al . used whole-genome sequencing to investigate the contribution of rare mutations among poultry workers who can be exposed to high levels of H7N9. Multiple defective single-nucleotide variants in the myxovirus resistance Mx1 locus were prevalent in H7N9 patients. In vitro infection experiments and influenza polymerase activity assays showed that 14 of the 17 MxA protein variants had no antiviral activity. Thus, individuals with such genetic vulnerabilities, when exposed to high virus loads, may act as crucibles for transmission of virulent new influenza subtypes. —CA

Innate immunity facilitates immediate defense against invading pathogens throughout all organs and tissues but also mediates tissue homeostasis and repair, thereby playing a key role in health and development. Recognition of pathogens is mediated by germline-encoded PRRs. Depending on the specific PRRs triggered, ligand binding leads to phagocytosis and pathogen killing and the controlled release of immune-modulatory factors such as IFNs, cytokines, or chemokines. PRR-mediated and other innate immune responses do not only prevent uncontrolled replication of intruding pathogens but also contribute to the tailoring of an effective adaptive immune response. Therefore, hereditary or acquired immunodeficiencies impairing innate responses may paradoxically cause severe immunopathology in patients. This can occur in the context of, but also independently of an increased microbial burden. It can include pathogen-dependent organ damage, autoinflammatory syndromes, and neurodevelopmental or neurodegenerative diseases. Here, we discuss the current state of research of several different such immune paradoxes. Understanding the underlying mechanisms causing immunopathology as a consequence of failures of innate immunity may help to prevent life-threatening disease.

Die migrantische Mobilität im Sommer 2015 hat die europäische Flüchtlingspolitik auf den Kopf gestellt. Rechte und konservative Kräfte wurden bestärkt, aber auch die Solidaritätserfahrungen hallen immer noch nach. Wie steht es nun um die Kämpfe der Migration? Welche Kräfte haben sich durchgesetzt und welche Verschiebungen haben sich diskursiv und politisch ergeben? Und was bedeutet dies für emanzipatorische, pro-migrantische Perspektiven? Die Forschungsgruppe »Beyond Summer 15« diskutiert diese Transformation des Migrationsregimes und zeigt u.a. in den Bereichen Recht, öffentliche Debatten, zivilgesellschaftliche Interventionen und Arbeitsmarkt auf, wie um Migration gerungen wird.

Zoonotic avian influenza A virus (IAV) infections are rare. Sustained transmission of these IAVs between humans has not been observed, suggesting a role for host genes. We used whole-genome sequencing to compare avian IAV H7N9 patients with healthy controls and observed a strong association between H7N9 infection and rare, heterozygous single-nucleotide variants in the

Social support is linked to a myriad of positive health outcomes, yet little is understood about its potential role on frailty development among older men who have sex with men (MSM). We evaluated data from 929 MSM aged 40-81 years enrolled in the MACS Health Aging sub-study. Social support (Social Provisions Scale[SPS-24]; range 24-96) was high, though slightly lower among the HIV-positive versus HIV-negative men (median: 80 vs. 82, p=0.12). Each SD increase in social support associated with a 21% decrease in incident frailty (Fried phenotype), independent of age, race, and education (aIRR=0.79, IQR[0.65, 0.97]), though attenuated after adjustment for depressive symptoms. This protective association was observed to be strongest among HIV-positive MSM. High social support is a strength among older MSM, which associates with positive frailty outcomes. Assessing and strengthening social support systems may have potential as a psychosocial component of frailty interventions.

Investigating the causes of unethical behaviors in academia, such as scientific misconduct, has become a highly important research subject. The current performance measurement practices (e.g., equating research performance with the number of publications in top-tier journals) are frequently referred to as being responsible for scientists’ unethical behaviors. We conducted qualitative semi-structured interviews with different stakeholders of the higher education system (e.g., professors and policy makers; N = 43) to analyze the influence of performance measurement on scientists’ behavior. We followed a three-step coding procedure and found (1) that the participants described a variety of positive behavioral consequences (e.g., higher productivity) but mainly negative behavioral consequences (e.g., questionable publishing practices) of current performance measurement practices in academia; (2) that scientists’ behavior can be described as gaming performance measurement (i.e., achieving performance goals by reducing performance quality and focusing on those tasks that are measured); and (3) that gaming performance measurement shares the same characteristics as deviant workplace behavior (i.e., a voluntary violation of organizational norms that harms the university). We discuss that gaming performance measurement has not been considered as a type of deviant workplace behavior in the previous literature. Furthermore, we draw from research on deviant workplace behavior and goal setting to discuss psychological processes that may underlie gaming performance measurement. Our results indicate the importance of connecting literature on deviant workplace behavior and goal setting to advance our understanding of gaming performance measurement.

ZusammenfassungDer Begriff der ‚Willkommenskultur‘ ist seit 2015 gesamtgesellschaftlich präsent. Von wem wird er genutzt, und mit welchen Absichten? Der Beitrag resümiert die mediale und politische Verhandlung von Ehrenamt im Rahmen der sogenannten ‚Flüchtlingskrise‘ nach 2015. Zu konstatieren sind in diesem Zusammenhang nicht nur die Nutzbarmachung von Engagement für ein Krisennarrativ der Überforderung, sondern auch Tendenzen der Entprofessionalisierung Sozialer Arbeit und staatliche Disziplinierungsversuche zivilgesellschaftlichen Engagements. Gleichzeitig finden im Schatten der ‚Willkommenskultur‘ drastische Entrechtungen Asylsuchender statt. Vor diesem Hintergrund steht ehrenamtliches Engagement vor der Herausforderung, eine politische und demokratische Rolle einzunehmen und zu verteidigen.

Antagonistic interactions drive host-virus evolutionary arms-races, which often manifest as recurrent amino acid changes (i.e., positive selection) at their protein-protein interaction interfaces. Here, we investigated whether combinatorial mutagenesis of positions under positive selection in a host antiviral protein could enhance its restrictive properties. We tested ~700 variants of human MxA, generated by combinatorial mutagenesis, for their ability to restrict Thogoto orthomyxovirus (THOV). We identified MxA super-restrictors with increased binding to THOV NP target protein and 10-fold higher anti-THOV restriction relative to wild-type human MxA, the most potent naturally-occurring anti-THOV restrictor identified. Our findings reveal a means to elicit super-restrictor antiviral proteins by leveraging signatures of positive selection. Although some MxA super-restrictors of THOV were impaired in their restriction of H5N1 influenza A virus (IAV), other super-restrictor variants increased THOV restriction without impairment of IAV restriction. Thus, broadly acting antiviral proteins such as MxA mitigate breadth-versus-specificity tradeoffs that could otherwise constrain their adaptive landscape.

Infections with emerging and re-emerging arboviruses are of increasing concern for global health. Tick-transmitted RNA viruses of the genus Thogotovirus in the Orthomyxoviridae family have considerable zoonotic potential, as indicated by the recent emergence of Bourbon virus in the USA. To successfully infect humans, arboviruses have to escape the restrictive power of the interferon defense system. This is exemplified by the high sensitivity of thogotoviruses to the antiviral action of the interferon-induced myxovirus resistance protein A (MxA) that inhibits the polymerase activity of incoming viral ribonucleoprotein complexes. Acquiring resistance to human MxA would be expected to enhance the zoonotic potential of these pathogens. Therefore, we screened a panel of 10 different thogotovirus isolates obtained from various parts of the world for their sensitivity to MxA. A single isolate from Nigeria, Jos virus, showed resistance to the antiviral action of MxA in cell culture and in MxA-transgenic mice, whereas the prototypic Sicilian isolate SiAr126 was fully MxA-sensitive. Further analysis identified two amino acid substitutions (G327R and R328V) in the viral nucleoprotein as determinants for MxA resistance. Importantly, when introduced into SiAr126, the R328V mutation resulted in complete MxA escape of the recombinant virus, without causing any viral fitness loss. The escape mutation abolished viral nucleoprotein recognition by MxA and allowed unhindered viral growth in MxA-expressing cells and in MxA-transgenic mice. These findings demonstrate that thogotoviruses can overcome the species barrier by escaping MxA restriction and reveal that these tick-transmitted viruses may have a greater zoonotic potential than previously suspected., Author summary Thogotovirus infections are known to cause isolated human fatalities, yet the zoonotic potential of these tick-transmitted pathogens is still largely unexplored. In the present study, we examined if these viruses are able to escape the interferon-induced human MxA, thereby overcoming the human innate antiviral defense. Mx proteins constitute a class of interferon-induced antiviral effector molecules that efficiently block the intracellular replication of many viruses. Here, we studied the MxA sensitivity of various thogotovirus isolates and identified two amino acid residues in the viral nucleoprotein that caused resistance to MxA. One of these exchanges was sufficient to enable an otherwise MxA-sensitive thogotovirus to fully escape MxA restriction without causing any fitness loss. Our study explores the interplay of thogotoviruses with the innate antiviral host defense and sheds light on their zoonotic potential.

Only a minority of patients infected with seasonal influenza A viruses exhibit a severe or fatal outcome of infection, but the reasons for this inter-individual variability in influenza susceptibility are unclear. To gain further insights into the molecular mechanisms underlying this variability, we investigated naturally occurring allelic variations of the myxovirus resistance 1 (MX1) gene coding for the influenza restriction factor MxA. The interferon-induced dynamin-like GTPase consists of an N-terminal GTPase domain, a bundle signaling element, and a C-terminal stalk responsible for oligomerization and viral target recognition. We used online databases to search for variations in the MX1 gene. Deploying in vitro approaches, we found that non-synonymous variations in the GTPase domain cause the loss of antiviral and enzymatic activities. Furthermore, we showed that these amino acid substitutions disrupt the interface for GTPase domain dimerization required for the stimulation of GTP hydrolysis. Variations in the stalk were neutral or slightly enhanced or abolished MxA antiviral function. Remarkably, two other stalk variants altered MxA's antiviral specificity. Variations causing the loss of antiviral activity were found only in heterozygous carriers. Interestingly, the inactive stalk variants blocked the antiviral activity of WT MxA in a dominant-negative way, suggesting that heterozygotes are phenotypically MxA-negative. In contrast, the GTPase-deficient variants showed no dominant-negative effect, indicating that heterozygous carriers should remain unaffected. Our results demonstrate that naturally occurring mutations in the human MX1 gene can influence MxA function, which may explain individual variations in influenza virus susceptibility in the human population.

Summary Bacterial microcompartments (MCPs) are protein organelles that typically house toxic or volatile reaction intermediates involved in metabolic pathways. Engineering bacteria to express exogenous MCPs will allow these cells to gain useful functions involving molecule compartmentalization. We cloned a 38 kb region from the Salmonella enterica serovar Typhimurium genome containing the pdu 1,2 propanediol (1,2 PD) utilization and cob/cbi genes using the FRT‐Capture strategy to clone and transfer large genomic segments. We transferred this clone to a range of Gram‐negative bacteria and found the clone to be functional for 1,2 PD metabolism in a variety of species including S. Typhimurium Δpdu, Escherichia coli, Salmonella bongori, Klebsiella pneumoniae, Cronobacter sakazakii, Serratia marcescens, and different Pseudomonas species. We successfully isolated MCPs expressed from the clone from several, but not all, of these strains, and we observed this utilizing a range of different media and in the absence of protease inhibitor. We also present a mini‐prep protocol that allows rapid, small‐scale screening of strains for MCP production. To date, this is the first analysis of cloned, exogenous microcompartment expression across several different Gram‐negative backgrounds and provides a foundation for MCP use in a variety of bacterial species using a full, intact clone.

Human myxovirus resistance protein 1 (MxA) restricts a wide range of viruses and is closely related to the membrane-remodelling GTPase dynamin. The functions of MxA rely on domain rearrangements coupled with GTP hydrolysis cycles. To gain insight into this process, we studied real-time domain dynamics of MxA by single-molecule fluorescence resonance energy transfer. We find that the GTPase domain-bundle-signalling-element (BSE) region can adopt either an ‘open' or a ‘closed' conformation in all nucleotide-loading conditions. Whereas the open conformation is preferred in nucleotide-free, GDP·AlF4−-bound and GDP-bound forms, loading of GTP activates the relative movement between the two domains and alters the conformational preference to the ‘closed' state. Moreover, frequent relative movement was observed between BSE and stalk via hinge 1. On the basis of these results, we suggest how MxA molecules within a helical polymer collectively generate a stable torque through random GTP hydrolysis cycles. Our study provides mechanistic insights into fundamental cellular events such as viral resistance and endocytosis., MxA (myxovirus resistance protein A) is a viral restriction factor whose activity depends on self-assembly into polymeric rings and helical filaments. Here the authors reveal the conformational movements involved in generating torque within polymeric MxA molecules and the dynamic conformational changes that occur upon GTP loading and hydrolysis.

The human cytomegalovirus (HCMV)-encoded protein kinase, pUL97, is considered a cyclin-dependent kinase (CDK) ortholog, due to shared structural and functional characteristics. The primary mechanism of CDK activation is binding to corresponding cyclins, including cyclin T1, which is the usual regulatory cofactor of CDK9. This study provides evidence of direct interaction between pUL97 and cyclin T1 using yeast two-hybrid and co-immunoprecipitation analyses. Confocal immunofluorescence revealed partial colocalization of pUL97 with cyclin T1 in subnuclear compartments, most pronounced in viral replication centres. The distribution patterns of pUL97 and cyclin T1 were independent of HCMV strain and host cell type. The sequence domain of pUL97 responsible for the interaction with cyclin T1 was between amino acids 231-280. Additional co-immunoprecipitation analyses showed cyclin B1 and cyclin A as further pUL97 interaction partners. Investigation of the pUL97-cyclin T1 interaction in an ATP consumption assay strongly suggested phosphorylation of pUL97 by the CDK9/cyclin T1 complex in a substrate concentration-dependent manner. This is the first demonstration of interaction between a herpesviral CDK ortholog and cellular cyclins.

Because scholarly performance is multidimensional, many different criteria may influence appointment decisions. Previous studies on appointment preferences do not reveal how appointment committee members consider and weigh up different criteria when they evaluate candidates. We used adaptive choice-based conjoint analysis to identify scholars’ implicit appointment preferences. Junior and senior scholars (N = 721) from different scientific fields and countries took part in a hypothetical appointment procedure. In contrast to previous studies, we found that the criterion ‘acquired grants’ strongly influences scholars’ decisions. Multiple regressions showed how several factors contribute to differences in appointment preferences. Scholars from the U.S., for example, attach less importance to grants and international orientation and more importance to number of publications than scholars from other countries. Furthermore, we provide evidence for homophily effects, that is, scholars prefer candidates who are s...

Cyclin-dependent kinases (CDKs) are multifaceted regulators involved in the replication of human cytomegalovirus. Recently, we demonstrated an interaction of CDK9–cyclin T1 as well as viral CDK orthologue pUL97 with the viral regulator pUL69, thereby leading to pUL69-activating phosphorylation. Here, we demonstrate that colocalization and direct pUL69–cyclin T1 interaction is independent of viral strains and host cell types. In vitro phosphorylation of pUL69 by CDK9 or pUL97 did not occur in a single site-specific manner, but at multiple sites. The previously described fine-speckled nuclear aggregation of pUL69 was assigned to the late phase of viral replication. CDK inhibitors, including a novel inhibitor of the CDK-activating kinase CDK7, massively intensified this fine-speckled accumulation. Interestingly, we also observed spontaneous pUL69 accumulation in the absence of inhibitors at a lower frequency. These findings provide new insight into pUL69 kinase interregulation and emphasize the importance of pUL69 phosphorylation for correct intranuclear localization.

Myxovirus resistance (Mx) GTPases are induced by interferon and inhibit multiple viruses, including influenza and human immunodeficiency viruses. They have the characteristic domain architecture of dynamin-related proteins with an N-terminal GTPase (G) domain, a bundle signaling element, and a C-terminal stalk responsible for self-assembly and effector functions. Human MxA (also called MX1) is expressed in the cytoplasm and is partly associated with membranes of the smooth endoplasmic reticulum. It shows a protein concentration-dependent increase in GTPase activity, indicating regulation of GTP hydrolysis via G domain dimerization. Here, we characterized a panel of G domain mutants in MxA to clarify the role of GTP binding and the importance of the G domain interface for the catalytic and antiviral function of MxA. Residues in the catalytic center of MxA and the nucleotide itself were essential for G domain dimerization and catalytic activation. In pulldown experiments, MxA recognized Thogoto virus nucleocapsid proteins independently of nucleotide binding. However, both nucleotide binding and hydrolysis were required for the antiviral activity against Thogoto, influenza, and La Crosse viruses. We further demonstrate that GTP binding facilitates formation of stable MxA assemblies associated with endoplasmic reticulum membranes, whereas nucleotide hydrolysis promotes dynamic redistribution of MxA from cellular membranes to viral targets. Our study highlights the role of nucleotide binding and hydrolysis for the intracellular dynamics of MxA during its antiviral action.

This study aims to explore the relationship between the demand for leadership and management skills in job advertisements and the performance of knowledge-intensive organizations. Analyzing univers...

Cyclin-dependent protein kinases (CDKs) are important regulators of cellular processes and are functionally integrated into the replication of human cytomegalovirus (HCMV). Recently, a regulatory impact of CDK activity on the viral mRNA export factor pUL69 was shown. Here, specific aspects of the mode of interaction between CDK9/cyclin T1 and pUL69 are described. Intracellular localization was studied in the presence of a novel selective CDK9 inhibitor, R22, which exerts anti-cytomegaloviral activity in vitro. A pronounced R22-induced formation of nuclear speckled aggregation of pUL69 was demonstrated. Multi-labelling confocal laser-scanning microscopy revealed that CDK9 and cyclin T1 co-localized perfectly with pUL69 in individual speckles. The effects were similar to those described recently for the broad CDK inhibitor roscovitine. Co-immunoprecipitation and yeast two-hybrid analyses showed that cyclin T1 interacted with both CDK9 and pUL69. The interaction region of pUL69 for cyclin T1 could be attributed to aa 269–487. Moreover, another component of CDK inhibitor-induced speckled aggregates was identified with RNA polymerase II, supporting earlier reports that strongly suggested an association of pUL69 with transcription complexes. Interestingly, when using a UL69-deleted recombinant HCMV, no speckled aggregates were formed by CDK inhibitor treatment. This indicated that pUL69 is the defining component of aggregates and generally may represent a crucial viral interactor of cyclin T1. In conclusion, these data emphasize that HCMV inter-regulation with CDK9/cyclin T1 is at least partly based on a pUL69–cylin T1 interaction, thus contributing to the importance of CDK9 for HCMV replication.

Human myxovirus resistance protein A (MxA) is an interferon-induced GTPase and part of the host cell defense against influenza viruses. It has a three-domain architecture with an amino-terminal GTPase (G) domain and a carboxy-terminal stalk responsible for oligomerization and viral target recognition. The MX1 gene, encoding MxA, is highly conserved and only a few single nucleotide polymorphisms are described in the human population. In this study we investigate whether and how allelic variations in MxA influence its antiviral function. Two rare nucleotide changes identified in the MX1 gene of healthy individuals result in amino acid exchanges at positions 255 and 268 in the G domain. GTPase and Minireplicon assays revealed that the V268M exchange showed some reduction in GTP hydrolysis, but only a slightly reduced antiviral activity against influenza A virus. However, the G255E exchange caused a complete loss of GTPase and antiviral activity of MxA. Further biochemical analyses of this naturally occurring mutation revealed the central role of GTP binding and hydrolysis for the antiviral mechanism of MxA. Using bioinformatics tools we are currently identifying additional allelic variations in MxA. Their characterization will answer the question how polymorphisms in the MX1 gene influence the antiviral capacity of MxA and whether these are enriched in patients suffering from severe influenza as has been described recently for IFITM3, another interferon-induced antiviral restriction factor.