North American wintering mallards infected with highly pathogenic avian influenza show few signs of altered local or migratory movements.

Avian influenza viruses pose a threat to wildlife and livestock health. The emergence of highly pathogenic avian influenza (HPAI) in wild birds and poultry in North America in late 2021 was the first such outbreak since 2015 and the largest outbreak in North America to date. Despite its prominence and economic impacts, we know relatively little about how HPAI spreads in wild bird populations. In January 2022, we captured 43 mallards (Anas platyrhynchos) in Tennessee, USA, 11 of which were actively infected with HPAI. These were the first confirmed detections of HPAI H5N1 clade 2.3.4.4b in the Mississippi Flyway. We compared movement patterns of infected and uninfected birds and found no clear differences; infected birds moved just as much during winter, migrated slightly earlier, and migrated similar distances as uninfected birds. Infected mallards also contacted and shared space with uninfected birds while on their wintering grounds, suggesting ongoing transmission of the virus. We found no differences in body condition or survival rates between infected and uninfected birds. Together, these results show that HPAI H5N1 clade 2.3.4.4b infection was unrelated to body condition or movement behavior in mallards infected at this location during winter; if these results are confirmed in other seasons and as HPAI H5N1 continues to evolve, they suggest that these birds could contribute to the maintenance and dispersal of HPAI in North America. Further research on more species across larger geographic areas and multiple seasons would help clarify potential impacts of HPAI on waterfowl and how this emerging disease spreads at continental scales, across species, and potentially between wildlife and domestic animals.

Naturally Acquired Antibodies to Influenza A Virus in Fall-Migrating North American Mallards.

Although waterfowl are the primary reservoir for multiple subtypes of influenza A virus (IAV), our understanding of population immunity in naturally infected waterfowl is poorly understood. Population immunity may be an important driver of seasonal subtype predominance in waterfowl populations and may affect the potential for establishment of introduced IAV such as the Eurasian-like A/Goose/Guangdong/1/1996 lineage in these populations. Here, we examine the prevalence of naturally acquired antibodies to nucleoprotein (NP), hemagglutinin (H3, H4, H5), and neuraminidase (N1, N2, N6, N8) in early migrating mallards (Anas platyrhynchos) sampled in Northwest Minnesota during staging and early fall migration in September 2014, 2015, 2017, and 2018. Serologic results were compared to historic and contemporary virus isolation results from these same study sites. The prevalence of antibodies to NP ranged from 60.8−76.1% in hatch-year (HY) birds and from 86.0−92.7% in after-hatch-year (AHY, >1-year-old) mallards indicating a high level of previous infection with IAV early in the fall migration season. Neutralizing antibodies were detected against H3, H4, and H5 in all years as were antibodies to N1, N2, N6, and N8. A high proportion of NP seropositive ducks tested positive for antibodies to multiple HA and NA subtypes, and this was more common in the AHY age class. Antibody prevalence to the HA and NA subtypes included in this study were consistent with the predominance of H4N6 in these populations during all years and reflected a broadening of the antibody response with age. Additional work is needed to document the longevity of these immune responses, if and how they correlate with protection against IAV transmission, infection, and disease, and if, as detected in this study, they adequately describe the true extent of exposure to IAV or specific HA or NA subtypes.

Telehealth interventions: remote monitoring and consultations for people with chronic obstructive pulmonary disease (COPD).

BACKGROUND: Chronic obstructive pulmonary disease (COPD, including bronchitis and emphysema) is a chronic condition causing shortness of breath, cough, and exacerbations leading to poor health outcomes. Face-to-face visits with health professionals can be hindered by severity of COPD or frailty, and by people living at a distance from their healthcare provider and having limited access to services. Telehealth technologies aimed at providing health care remotely through monitoring and consultations could help to improve health outcomes of people with COPD. OBJECTIVES: To assess the effectiveness of telehealth interventions that allow remote monitoring and consultation and multi-component interventions for reducing exacerbations and improving quality of life, while reducing dyspnoea symptoms, hospital service utilisation, and death among people with COPD. SEARCH METHODS: We identified studies from the Cochrane Airways Trials Register. Additional sources searched included the US National Institutes of Health Ongoing Trials Register, the World Health Organization International Clinical Trials Registry Platform, and the IEEEX Xplore Digital Library. The latest search was conducted in April 2020. We used the GRADE approach to judge the certainty of evidence for outcomes. SELECTION CRITERIA: Eligible randomised controlled trials (RCTs) included adults with diagnosed COPD. Asthma, cystic fibrosis, bronchiectasis, and other respiratory conditions were excluded. Interventions included remote monitoring or consultation plus usual care, remote monitoring or consultation alone, and mult-component interventions from all care settings. Quality of life scales included St George's Respiratory Questionnaire (SGRQ) and the COPD Assessment Test (CAT). The dyspnoea symptom scale used was the Chronic Respiratory Disease Questionnaire Self-Administered Standardized Scale (CRQ-SAS). DATA COLLECTION AND ANALYSIS: We used standard Cochrane methodological procedures. We assessed confidence in the evidence for each primary outcome using the GRADE method. Primary outcomes were exacerbations, quality of life, dyspnoea symptoms, hospital service utilisation, and mortality; a secondary outcome consisted of adverse events. MAIN RESULTS: We included 29 studies in the review (5654 participants; male proportion 36% to 96%; female proportion 4% to 61%). Most remote monitoring interventions required participants to transfer measurements using a remote device and later health professional review (asynchronous). Only five interventions transferred data and allowed review by health professionals in real time (synchronous). Studies were at high risk of bias due to lack of blinding, and certainty of evidence ranged from moderate to very low. We found no evidence on comparison of remote consultations with or without usual care. Remote monitoring plus usual care (8 studies, 1033 participants) Very uncertain evidence suggests that remote monitoring plus usual care may have little to no effect on the number of people experiencing exacerbations at 26 weeks or 52 weeks. There may be little to no difference in effect on quality of life (SGRQ) at 26 weeks (very low to low certainty) or on hospitalisation (all-cause or COPD-related; very low certainty). COPD-related hospital re-admissions are probably reduced at 26 weeks (hazard ratio 0.42, 95% confidence interval (CI) 0.19 to 0.93; 106 participants; moderate certainty). There may be little to no difference in deaths between intervention and usual care (very low certainty). We found no evidence for dyspnoea symptoms or adverse events. Remote monitoring alone (10 studies, 2456 participants) Very uncertain evidence suggests that remote monitoring may result in little to no effect on the number of people experiencing exacerbations at 41 weeks (odds ratio 1.02, 95% CI 0.67 to 1.55). There may be little to no effect on quality of life (SGRQ total at 17 weeks, or CAT at 38 and 52 weeks; very low certainty). There may be little to no effect on dyspnoea symptoms on the CRQ-SAS at 26 weeks (low certainty). There may be no difference in effects on the number of people admitted to hospital (very low certainty) or on deaths (very low certainty). We found no evidence for adverse events. Multi-component interventions with remote monitoring or consultation component (11 studies, 2165 participants) Very uncertain evidence suggests that multi-component interventions may have little to no effect on the number of people experiencing exacerbations at 52 weeks. Quality of life at 13 weeks may improve as seen in SGRQ total score (mean difference -9.70, 95% CI -18.32 to -1.08; 38 participants; low certainty) but not at 26 or 52 weeks (very low certainty). COPD assessment test (CAT) scores may improve at a mean of 38 weeks, but evidence is very uncertain and interventions are varied. There may be little to no effect on the number of people admitted to hospital at 33 weeks (low certainty). Multi-component interventions are likely to result in fewer people re-admitted to hospital at a mean of 39 weeks (OR 0.50, 95% CI 0.31 to 0.81; 344 participants, 3 studies; moderate certainty). There may be little to no difference in death at a mean of 40 weeks (very low certainty). There may be little to no effect on people experiencing adverse events (very low certainty). We found no evidence for dyspnoea symptoms. AUTHORS' CONCLUSIONS: Remote monitoring plus usual care provided asynchronously may not be beneficial overall compared to usual care alone. Some benefit is seen in reduction of COPD-related hospital re-admissions, but moderate-certainty evidence is based on one study. We have not found any evidence for dyspnoea symptoms nor harms, and there is no difference in fatalities when remote monitoring is provided in addition to usual care. Remote monitoring interventions alone are no better than usual care overall for health outcomes. Multi-component interventions with asynchronous remote monitoring are no better than usual care but may provide short-term benefit for quality of life and may result in fewer re-admissions to hospital for any cause. We are uncertain whether remote monitoring is responsible for the positive impact on re-admissions, and we are unable to discern the long-term benefits of receiving remote monitoring as part of patient care. Owing to paucity of evidence, it is unclear which COPD severity subgroups would benefit from telehealth interventions. Given there is no evidence of harm, telehealth interventions may be beneficial as an additional health resource depending on individual needs based on professional assessment. Larger studies can determine long-term effects of these interventions.

Experimental Infection of Domestic Piglets (Sus scrofa) with Rift Valley Fever Virus.

Rift Valley fever phlebovirus (RVFV) is a mosquito-transmitted phlebovirus (Family: Phenuiviridae, Order: Bunyavirales) causing severe neonatal mortality and abortion primarily in domestic ruminants. The susceptibility of young domestic swine to RVFV and this species' role in geographic expansion and establishment of viral endemicity is unclear. Six commercially bred Landrace-cross piglets were inoculated subcutaneously with 105 plaque-forming units of RVFV ZH501 strain and two piglets received a sham inoculum. All animals were monitored for clinical signs, viremia, viral shedding, and antibody response for 14 days. Piglets did not develop evidence of clinical disease, become febrile, or experience decreased weight gain during the study period. A brief lymphopenia followed by progressive lymphocytosis was observed following inoculation in all piglets. Four piglets developed a brief viremia for 2 days post-inoculation and three of these had detectable virus in oronasal secretions three days post-inoculation. Primary inoculated piglets seroconverted and those that developed detectable viremias had the highest titers assessed by serum neutralization (1:64-1:256). Two viremic piglets had a lymphoplasmacytic encephalitis with glial nodules; RVFV was not detected by immunohistochemistry in these sections. While young piglets do not appear to readily develop clinical disease following RVFV infection, results suggest swine could be subclinically infected with RVFV.

The Effect of Maternal Antibodies on Clinical Response to Infection with Epizootic Hemorrhagic Disease Virus in White-Tailed Deer (Odocoileus virginianus) Fawns.

We investigated whether naturally acquired maternal antibodies to epizootic hemorrhagic disease virus serotype 2 (EHDV-2) would protect white-tailed deer (Odocoileus virginianus) fawns against infection and clinical disease following an EHDV-2 challenge. We compared viremia and clinical response in 27-47-d-old, experimentally infected fawns with and without maternally derived antibodies to EHDV-2. Mild to moderate clinical signs were observed in four seronegative (maternal antibody-negative) fawns, which were viremic from 3 to 14 d postinoculation. Individual peak blood virus titers for seronegative fawns ranged from 104.3 to 106.3 median tissue culture infective doses (TCID50)/mL. In contrast, clinical signs were not observed in seropositive (maternal antibody-positive) fawns and a transient low-level viremia (≤102.4 TCID50/mL) occurred in two of six fawns. Our results indicated that the presence of maternally derived EHDV-2 antibodies in fawns prevents or greatly reduces clinical disease and the level and duration of EHDV-2 viremia.

Influenza A Viruses in Whistling Ducks (Subfamily Dendrocygninae).

As compared to other Anseriformes, data related to influenza A virus (IAV) detection and isolation, and IAV antibody detection in whistling ducks (Dendrocygna spp. and Thalassornis leuconotus; subfamily Dendrocygninae) are limited. To better evaluate the potential role of whistling ducks in the epidemiology of IAV, we (1) conducted surveillance for IAV from black-bellied whistling ducks (BBWD, Dendrocygnaautumnalis) sampled in coastal Louisiana, USA, during February 2018 and 2019, and (2) reviewed the published literature and Influenza Resource Database (IRD) that reported results of IAV surveillance of whistling ducks. In the prospective study, from 166 BBWD sampled, one H10N7 IAV was isolated (0.6% prevalence), and overall blocking enzyme-linked immunosorbent assay (bELISA) antibody seroprevalence was 10%. The literature review included publications and data in the IRD from 1984 to 2020 that reported results from nearly 5000 collected samples. For any given collection, the IAV isolation rate never exceeded 5.5%, and seroprevalence estimates ranged from 0 to 42%. Results from our prospective study in Louisiana are consistent with this historic literature; however, although all data consistently demonstrated a low prevalence of infection, the potential role of this species in the epidemiology of IAV should not be totally discounted. In sum, whistling ducks can be infected with IAV, they represent important species on many areas where waterfowl winter, and their distribution across the globe appears to be changing.

Influenza A Viruses in Ruddy Turnstones (Arenaria interpres); Connecting Wintering and Migratory Sites with an Ecological Hotspot at Delaware Bay.

Each May for over three decades, avian influenza A viruses (IAVs) have been isolated from shorebirds and gulls (order Charadriiformes) at Delaware Bay (DE Bay), USA, which is a critical stopover site for shorebirds on their spring migration to arctic breeding grounds. At DE Bay, most isolates have been recovered from ruddy turnstones (Arenaria interpres), but it is unknown if this species is involved in either the maintenance or movement of these viruses outside of this site. We collected and tested fecal samples from 2823 ruddy turnstones in Florida and Georgia in the southeastern United States during four winter/spring sample periods-2010, 2011, 2012, and 2013-and during the winters of 2014/2015 and 2015/2016. Twenty-five low pathogenicity IAVs were recovered representing five subtypes (H3N4, H3N8, H5N9, H6N1, and H12N2). Many of these subtypes matched those recovered at DE Bay during the previous year or that year's migratory cycle, suggesting that IAVs present on these southern wintering areas represent a source of virus introduction to DE Bay via migrating ruddy turnstones. Analyses of all IAV gene segments of H5N9 and H6N1 viruses recovered from ruddy turnstones at DE Bay during May 2012 and from the southeast during the spring of 2012 revealed a high level of genetic relatedness at the nucleotide level, suggesting that migrating ruddy turnstones move IAVs from wintering grounds to the DE Bay ecosystem.

EBV BCL-2 homologue BHRF1 drives chemoresistance and lymphomagenesis by inhibiting multiple cellular pro-apoptotic proteins.

Epstein-Barr virus (EBV), which is ubiquitous in the adult population, is causally associated with human malignancies. Like many infectious agents, EBV has evolved strategies to block host cell death, including through expression of viral homologues of cellular BCL-2 pro-survival proteins (vBCL-2s), such as BHRF1. Small molecule inhibitors of the cellular pro-survival BCL-2 family proteins, termed 'BH3-mimetics', have entered clinical trials for blood cancers with the BCL-2 inhibitor venetoclax already approved for treatment of therapy refractory chronic lymphocytic leukaemia and acute myeloid leukaemia in the elderly. The generation of BH3-mimetics that could specifically target vBCL-2 proteins may be an attractive therapeutic option for virus-associated cancers, since these drugs would be expected to only kill virally infected cells with only minimal side effects on normal healthy tissues. To achieve this, a better understanding of the contribution of vBCL-2 proteins to tumorigenesis and insights into their biochemical functions is needed. In the context of Burkitt lymphoma (BL), BHRF1 expression conferred strong resistance to diverse apoptotic stimuli. Furthermore, BHRF1 expression in mouse haematopoietic stem and progenitor cells accelerated MYC-induced lymphoma development in a model of BL. BHRF1 interacts with the cellular pro-apoptotic BCL-2 proteins, BIM, BID, PUMA and BAK, but its capability to inhibit apoptosis could not be mapped solely to one of these interactions, suggesting plasticity is a key feature of BHRF1. Site-directed mutagenesis revealed a site in BHRF1 that was critical for its interaction with PUMA and blocking DNA-damage-induced apoptosis, identifying a potentially therapeutically targetable vulnerability in BHRF1.

Consistency of Recommendations for Evaluation and Management of Hypertension.

Importance: Hypertension is very common, but guideline recommendations for hypertension have been controversial, are of increasing interest, and have profound implications. Objective: To systematically assess the consistency of recommendations regarding hypertension management across clinical practice guidelines (CPGs). Design, Setting, and Participants: This cross-sectional study of hypertension management recommendations included CPGs that had been published as of April 2018. Two point-of-care resources that provided graded recommendations were included for secondary analyses. Discrete and unambiguous specifications of the population, intervention, and comparison states were used to define a series of reference recommendations. Three raters reached consensus on coding the direction and strength of each recommendation made by each CPG. Three independent raters reached consensus on the importance of each reference recommendation. Main Outcomes and Measures: The main outcomes were rates of consistency for direction and strength among CPGs. Sensitivity analyses testing the robustness were conducted by excluding recommendation statements that were described as insufficient evidence, excluding single recommendation sources, and stratifying by importance of recommendations. Results: The analysis included 8 CPGs with a total of 71 reference recommendations, 68 of which had clear recommendations from 2 or more CPGs. Across CPGs, 22 recommendations (32%) were consistent in direction and strength, 18 recommendations (27%) were consistent in direction but inconsistent in strength, and 28 recommendations (41%) were inconsistent in direction. The rate of consistency was lower in secondary analyses. When insufficient evidence ratings were excluded, there was still substantial inconsistency, and a leave-one-out sensitivity analysis suggested the inconsistency could not be attributed to any single recommendation source. Inconsistency in direction was more common for recommendations deemed to be of lower importance (11 of 20 recommendations [55%]), but 17 of 48 high-importance recommendations (35%) had inconsistency in direction. Conclusions and Relevance: Hypertension is a common chronic condition with widespread expectations surrounding guideline-based care, yet CPGs have a high rate of inconsistency. Further investigations should determine the reasons for inconsistency, the implications for recommendation development, and the role of synthesis across recommendations for optimal guidance of clinical care.

Proteolytic and Opportunistic Breaching of the Basement Membrane Zone by Immune Cells during Tumor Initiation.

Cancer-related inflammation impacts significantly on cancer development and progression. From early stages, neutrophils and macrophages are drawn to pre-neoplastic cells in the epidermis, but before directly interacting, they must first breach the underlying extracellular matrix barrier layer that includes the basement membrane. Using several different skin cancer models and a collagen I-GFP transgenic zebrafish line, we have undertaken correlative light and electron microscopy (CLEM) to capture the moments when immune cells traverse the basement membrane. We show evidence both for active proteolytic burrowing and for the opportunistic use of pre-existing weak spots in the matrix layer. We show that these small holes, as well as much larger, cancer cell-generated or wound-triggered gaps in the matrix barrier, provide portals for immune cells to access cancer cells in the epidermis and thus are rate limiting in cancer progression.

Influenza A Prevalence and Subtype Diversity in Migrating Teal Sampled Along the United States Gulf Coast.

Wild birds in the order Anseriformes are important reservoirs for influenza A viruses (IAVs); however, IAV prevalence and subtype diversity may vary by season, even at the same location. To better understand the ecology of IAV during waterfowl migration through the Gulf Coast of the United States (Louisiana and Texas), surveillance of blue-winged (Spatula discors) and American green-winged (Anas carolinensis) teal was conducted. The surveillance was done annually during the spring (live capture; 2012-17) and fall (hunter harvested; 2007-17) at times inferred to coincide with northward and southward movements, respectively, for these waterfowl species. During spring migration, 266 low pathogenicity (LP) IAV positive samples were recovered from 7547 paired cloacal-oropharyngeal (COP) samples (prevalence, 3.5%; annual range, 1.3%-8.4%). During fall migration, 650 LP IAV-positive samples were recovered from 9493 COP samples (prevalence, 6.8%; annual range, 0.4%-23.5%). Overall, 34 and 20 different IAV subtypes were recovered during fall and spring sampling, respectively. Consistent with previous results for fall migrating ducks, H3 and H4 hemagglutinin (HA) subtypes were most common; however, H4 subtype viruses predominated every year. This is in contrast to the predominance of LP H7 and H10 HA subtype viruses during spring. The N6 and N8 neuraminidase subtypes, which were usually associated with H4, were most common during fall; the N6 subtype was not recovered in the spring. These consistent seasonal trends in IAV subtype detection in teal are currently not understood and highlight the need for further research regarding potential drivers of spatiotemporal patterns of infection, such as population immunity.

Prevalencia del virus de la influenza A y diversidad de subtipos en cercetas migratorias muestreadas a lo largo de la costa del Golfo en los Estados Unidos. Las aves silvestres del orden Anseriformes son reservorios importantes para los virus de la influenza A; sin embargo, la prevalencia del virus de influenza aviar y la diversidad de subtipos puede variar según la temporada, incluso en el mismo lugar. Para comprender mejor la ecología del virus de la influenza aviar durante la migración de aves acuáticas a través de la Costa del Golfo en los Estados Unidos (Louisiana y Texas), se llevó a cabo el muestreo anual de cercetas de alas azules (Spatula discors) y de cercetas americanas (Anas carolinensis) tanto en primavera (capturadas vivas entre los años 2012-17) como en otoño (obtenidas por cazadores, entre los años 2007-17), periodos que se han inferido que a veces coinciden con los movimientos hacia el norte y hacia el sur, respectivamente, para estas especies de aves acuáticas. Durante la migración de primavera, se recuperaron 266 muestras positivas para influenza aviar de baja patogenicidad de 7547 muestras pareadas cloacales y orofaríngeas (prevalencia, 3.5%, rango anual de 1.3% a 8.4%). Durante la migración de otoño, se recuperaron 650 muestras positivas de 9493 muestras pareadas cloacales y orofaríngeas (prevalencia, 6.8%, rango anual, de 0.4% a 23.5%). En general, se recuperaron 34 y 20 subtipos diferentes de virus de la influenza aviar durante los muestreos de otoño y primavera, respectivamente. Consistente con los resultados anteriores para patos que migran en el otoño, los subtipos de hemoaglutinina H3 y H4 fueron los más comunes; sin embargo, los virus del subtipo H4 predominaron todos los años. Esto contrasta con la predominancia del subtipo H7 y H10 de baja patogenicidad durante la primavera. Los subtipos de neuraminidasa N6 y N8, que generalmente se asociaron con subtipos H4, fueron los más comunes durante el otoño; el subtipo N6 no se recuperó en la primavera. Estas tendencias estacionales constantes en la detección de subtipos del virus de influenza aviar en cercetas actualmente no se comprenden completamente y resaltan la necesidad de más investigación con respecto a los posibles factores determinates de los patrones espaciotemporales de infección, como la inmunidad de la población.

EXPERIMENTAL INFECTION OF WHITE-TAILED DEER (ODOCOILEUS VIRGINIANUS) WITH BLUETONGUE VIRUS SEROTYPE 3.

Bluetongue virus serotype 3 (BTV-3) has been found in the US since 1999 and was recently identified in white-tailed deer (WTD; Odocoileus virginianus) found dead in Virginia, US and West Virginia, US in 2016. Bluetongue viruses are known to cause pathologic changes in WTD; however, the relative virulence and pathogenicity of BTV-3 in WTD is unknown. In our study, eight WTD fawns, 6-12 wk old, were needle inoculated subcutaneously with a field isolate of BTV-3, with one fawn shaminoculated as a control during July 2017; all were monitored to determine the pathogenicity of BTV-3 in WTD. All inoculated fawns developed viremias that were first detected on postinoculation day (PID), 3 with peak titers on PID 5 by both quantitative reverse-transcription PCR (qRT-PCR) and virus isolation. The sham-inoculated control fawn also became viremic on PID 12, presumably through contact with infected fawns. Mild clinical signs, including periorbital edema and hyperemia, were first seen on PID 5. None of the fawns developed a significant febrile response, clinical pathology changes, or BTV-3 neutralizing antibodies. The cytokines TNF-α, IL-1ß, and IFN-α were not detected by commercial enzyme-linked immunosorbent assays developed for bovids. The absence of severe clinical disease, fibrinogenemia, thrombocytopenia, and leukopenia, along with the lack of seroconversion and a detectable cytokine response during the study period, is atypical when compared to previous experimental BTV serotype infections in WTD but may be related to the young age of these deer, possible attenuation of the BTV-3 strain used, innate resistance or, in some cases to maternally derived antibody to other BTV serotypes.

Drosophila immune cells extravasate from vessels to wounds using Tre1 GPCR and Rho signaling.

Inflammation is pivotal to fight infection, clear debris, and orchestrate repair of injured tissues. Although Drosophila melanogaster have proven invaluable for studying extravascular recruitment of innate immune cells (hemocytes) to wounds, they have been somewhat neglected as viable models to investigate a key rate-limiting component of inflammation-that of immune cell extravasation across vessel walls-due to their open circulation. We have now identified a period during pupal development when wing hearts pulse hemolymph, including circulating hemocytes, through developing wing veins. Wounding near these vessels triggers local immune cell extravasation, enabling live imaging and correlative light-electron microscopy of these events in vivo. We show that RNAi knockdown of immune cell integrin blocks diapedesis, just as in vertebrates, and we uncover a novel role for Rho-like signaling through the GPCR Tre1, a gene previously implicated in the trans-epithelial migration of germ cells. We believe this new Drosophila model complements current murine models and provides new mechanistic insight into immune cell extravasation.

Coordinated repression of BIM and PUMA by Epstein-Barr virus latent genes maintains the survival of Burkitt lymphoma cells.

While the association of Epstein-Barr virus (EBV) with Burkitt lymphoma (BL) has long been recognised, the precise role of the virus in BL pathogenesis is not fully resolved. EBV can be lost spontaneously from some BL cell lines, and these EBV-loss lymphoma cells reportedly have a survival disadvantage. Here we have generated an extensive panel of EBV-loss clones from multiple BL backgrounds and examined their phenotype comparing them to their isogenic EBV-positive counterparts. We report that, while loss of EBV from BL cells is rare, it is consistently associated with an enhanced predisposition to undergo apoptosis and reduced tumorigenicity in vivo. Importantly, reinfection of EBV-loss clones with EBV, but surprisingly not transduction with individual BL-associated latent viral genes, restored protection from apoptosis. Expression profiling and functional analysis of apoptosis-related proteins and transcripts in BL cells revealed that EBV inhibits the upregulation of the proapoptotic BH3-only proteins, BIM and PUMA. We conclude that latent EBV genes cooperatively enhance the survival of BL cells by suppression of the intrinsic apoptosis pathway signalling via inhibition of the potent apoptosis initiators, BIM and PUMA.

Potential sperm contributions to the murine zygote predicted by in silico analysis.

Paternal contributions to the zygote are thought to extend beyond delivery of the genome and paternal RNAs have been linked to epigenetic transgenerational inheritance in different species. In addition, sperm-egg fusion activates several downstream processes that contribute to zygote formation, including PLC zeta-mediated egg activation and maternal RNA clearance. Since a third of the preimplantation developmental period in the mouse occurs prior to the first cleavage stage, there is ample time for paternal RNAs or their encoded proteins potentially to interact and participate in early zygotic activities. To investigate this possibility, a bespoke next-generation RNA sequencing pipeline was employed for the first time to characterise and compare transcripts obtained from isolated murine sperm, MII eggs and pre-cleavage stage zygotes. Gene network analysis was then employed to identify potential interactions between paternally and maternally derived factors during the murine egg-to-zygote transition involving RNA clearance, protein clearance and post-transcriptional regulation of gene expression. Our in silico approach looked for factors in sperm, eggs and zygotes that could potentially interact co-operatively and synergistically during zygote formation. At least five sperm RNAs (Hdac11, Fbxo2, Map1lc3a, Pcbp4 and Zfp821) met these requirements for a paternal contribution, which with complementary maternal co-factors suggest a wider potential for extra-genomic paternal involvement in the developing zygote.

Competition between influenza A virus subtypes through heterosubtypic immunity modulates re-infection and antibody dynamics in the mallard duck.

Our overall hypothesis is that host population immunity directed at multiple antigens will influence the prevalence, diversity and evolution of influenza A virus (IAV) in avian populations where the vast subtype diversity is maintained. To investigate how initial infection influences the outcome of later infections with homologous or heterologous IAV subtypes and how viruses interact through host immune responses, we carried out experimental infections in mallard ducks (Anas platyrhynchos). Mallards were pre-challenged with an H3N8 low-pathogenic IAV and were divided into six groups. At five weeks post H3N8 inoculation, each group was challenged with a different IAV subtype (H4N5, H10N7, H6N2, H12N5) or the same H3N8. Two additional pre-challenged groups were inoculated with the homologous H3N8 virus at weeks 11 and 15 after pre-challenge to evaluate the duration of protection. The results showed that mallards were still resistant to re-infection after 15 weeks. There was a significant reduction in shedding for all pre-challenged groups compared to controls and the outcome of the heterologous challenges varied according to hemagglutinin (HA) phylogenetic relatedness between the viruses used. There was a boost in the H3 antibody titer after re-infection with H4N5, which is consistent with original antigenic sin or antigenic seniority and suggest a putative strategy of virus evasion. These results imply competition between related subtypes that could regulate IAV subtype population dynamics in nature. Collectively, we provide new insights into within-host IAV complex interactions as drivers of IAV antigenic diversity that could allow the circulation of multiple subtypes in wild ducks.

Evidence for wild waterfowl origin of H7N3 influenza A virus detected in captive-reared New Jersey pheasants.

In August 2014, a low-pathogenic H7N3 influenza A virus was isolated from pheasants at a New Jersey gamebird farm and hunting preserve. In this study, we use phylogenetic analyses and calculations of genetic similarity to gain inference into the genetic ancestry of this virus and to identify potential routes of transmission. Results of maximum-likelihood (ML) and maximum-clade-credibility (MCC) phylogenetic analyses provide evidence that A/pheasant/New Jersey/26996-2/2014 (H7N3) had closely related H7 hemagglutinin (HA) and N3 neuraminidase (NA) gene segments as compared to influenza A viruses circulating among wild waterfowl in the central and eastern USA. The estimated time of the most recent common ancestry (TMRCA) between the pheasant virus and those most closely related from wild waterfowl was early 2013 for both the H7 HA and N3 NA gene segments. None of the viruses from waterfowl identified as being most closely related to A/pheasant/New Jersey/26996-2/2014 at the HA and NA gene segments in ML and MCC phylogenetic analyses shared ≥99 % nucleotide sequence identity for internal gene segment sequences. This result indicates that specific viral strains identified in this study as being closely related to the HA and NA gene segments of A/pheasant/New Jersey/26996-2/2014 were not the direct predecessors of the etiological agent identified during the New Jersey outbreak. However, the recent common ancestry of the H7 and N3 gene segments of waterfowl-origin viruses and the virus isolated from pheasants suggests that viral diversity maintained in wild waterfowl likely played an important role in the emergence of A/pheasant/New Jersey/26996-2/2014.

Genome Sequence of a Novel H14N7 Subtype Influenza A Virus Isolated from a Blue-Winged Teal (Anas discors) Harvested in Texas, USA.

We report here the complete genome sequence of a novel H14N7 subtype influenza A virus (IAV) isolated from a blue-winged teal (Anas discors) harvested in Texas, USA. The genomic characteristics of this IAV strain with a previously undetected subtype combination suggest recent viral evolution within the New World wild-bird IAV reservoir.

Mathematical modeling reveals differential effects of erythropoietin on proliferation and lineage commitment of human hematopoietic progenitors in early erythroid culture.

Erythropoietin is essential for the production of mature erythroid cells, promoting both proliferation and survival. Whether erythropoietin and other cytokines can influence lineage commitment of hematopoietic stem and progenitor cells is of significant interest. To study lineage restriction of the common myeloid progenitor to the megakaryocyte/erythroid progenitor of peripheral blood CD34(+) cells, we have shown that the cell surface protein CD36 identifies the earliest lineage restricted megakaryocyte/erythroid progenitor. Using this marker and carboxyfluorescein succinimidyl ester to track cell divisions in vitro, we have developed a mathematical model that accurately predicts population dynamics of erythroid culture. Parameters derived from the modeling of cultures without added erythropoietin indicate that the rate of lineage restriction is not affected by erythropoietin. By contrast, megakaryocyte/erythroid progenitor proliferation is sensitive to erythropoietin from the time that CD36 first appears at the cell surface. These results shed new light on the role of erythropoietin in erythropoiesis and provide a powerful tool for further study of hematopoietic progenitor lineage restriction and erythropoiesis.

Tribbles role in reproduction.

Tribbles (TRIB) proteins, a family of evolutionary conserved psuedokinase proteins, modulate various signalling pathways within the cell. The regulatory roles of TRIB make them an important part of a number of biological processes ranging from cell proliferation to metabolism, immunity, inflammation and carcinogenesis. Innate immune system plays a pivotal role during the regulation of reproductive processes that allows successful creation of an offspring. Its involvement initiates from fertilization of the oocyte by spermatozoon and lasts throughout early embryonic development, pregnancy and labour. Therefore, there is a close cooperation between the reproductive system and the innate immune system. Evidence from our lab has demonstrated that improper activation of the innate immune system can reduce embryo implantation, thus leading to infertility. Therefore, control mechanisms regulating the innate immune system function can be critical for successful reproductive events.