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Human macrophages are a natural host of many mycobacterium species, including Mycobacterium abscessus (M. abscessus), an emerging pathogen affecting immunocompromised and cystic fibrosis patients with few available treatments. The search for an effective treatment is hindered by the lack of a tractable in vitro intracellular infection model. Here, we established a reliable model for M. abscessus infection using human pluripotent stem cell-derived macrophages (hPSC-macrophages). hPSC differentiation permitted reproducible generation of functional macrophages that were highly susceptible to M. abscessus infection. Electron microscopy demonstrated that M. abscessus was present in the hPSC-macrophage vacuoles. RNA sequencing analysis revealed a time-dependent host cell response, with differing gene and protein expression patterns post-infection. Engineered tdTOMATO-expressing hPSC-macrophages with GFP-expressing mycobacteria enabled rapid image-based high-throughput analysis of intracellular infection and quantitative assessment of antibiotic efficacy. Our study describes the first to our knowledge hPSC-based model for M. abscessus infection, representing a novel and accessible system for studying pathogen-host interaction and drug discovery.

Interleukin-33 (IL-33) is an IL-1 family cytokine known to promote T-helper (Th) type 2 immune responses that are often deregulated in gastric cancer (GC). IL-33 is overexpressed in human gastric tumours suggesting a role in driving GC progression although a causal link has not been proven. Here, we investigated the impact of IL-33 genetic deficiency in the well-characterized

Background Household studies are crucial for understanding the transmission of SARS-CoV-2 infection, which may be underestimated from PCR testing of respiratory samples alone. We aim to combine assessment of household mitigation measures; nasopharyngeal, saliva and stool PCR testing; along with mucosal and systemic SARS-CoV-2 specific antibodies, to comprehensively characterise SARS-CoV-2 infection and transmission in households. Methods Between March and September 2020, we obtained samples from 92 participants in 26 households in Melbourne, Australia, in a 4-week period following onset of infection with ancestral SARS-CoV-2 variants. Results The secondary attack rate was 36% (24/66) when using nasopharyngeal swab (NPS) PCR positivity alone. However, when respiratory and non-respiratory samples were combined with antibody responses in blood and saliva, the secondary attack rate was 76% (50/66). SARS-CoV-2 viral load of the index case and household isolation measures were key factors that determine secondary transmission. In 27% (7/26) of households, all family members tested positive by NPS for SARS-CoV-2 and were characterised by lower respiratory Ct-values than low transmission families (Median 22.62 vs 32.91; IQR 17.06 to 28.67 vs 30.37 to 34.24). High transmission families were associated with enhanced plasma antibody responses to multiple SARS-CoV-2 antigens and the presence of neutralising antibodies. Three distinguishing saliva SARS-CoV-2 antibody features were identified according to age (IgA1 to Spike 1, IgA1 to nucleocapsid protein (NP), suggesting that adults and children generate distinct mucosal antibody responses during the acute phase of infection. Conclusion Utilising respiratory and non-respiratory PCR testing, along with measurement of SARS-CoV-2 specific local and systemic antibodies, provides a more accurate assessment of infection within households and highlights some of the immunological differences in response between children and adults.

The hallmarks of COVID-19 are higher pathogenicity and mortality in the elderly compared to children. Examining baseline SARS-CoV-2 cross-reactive immunological responses, induced by circulating human coronaviruses (hCoVs), is needed to understand such divergent clinical outcomes. Here we show analysis of coronavirus antibody responses of pre-pandemic healthy children (n = 89), adults (n = 98), elderly (n = 57), and COVID-19 patients (n = 50) by systems serology. Moderate levels of cross-reactive, but non-neutralizing, SARS-CoV-2 antibodies are detected in pre-pandemic healthy individuals. SARS-CoV-2 antigen-specific Fcγ receptor binding accurately distinguishes COVID-19 patients from healthy individuals, suggesting that SARS-CoV-2 infection induces qualitative changes to antibody Fc, enhancing Fcγ receptor engagement. Higher cross-reactive SARS-CoV-2 IgA and IgG are observed in healthy elderly, while healthy children display elevated SARS-CoV-2 IgM, suggesting that children have fewer hCoV exposures, resulting in less-experienced but more polyreactive humoral immunity. Age-dependent analysis of COVID-19 patients, confirms elevated class-switched antibodies in elderly, while children have stronger Fc responses which we demonstrate are functionally different. These insights will inform COVID-19 vaccination strategies, improved serological diagnostics and therapeutics., Antibody responses to SARS-CoV-2 are critical in the immune response to infection, but the potential cross-reactivity to other human corona viruses is poorly appreciated. Here the authors apply a systems based approach to characterise the antibody response in pre-pandemic cohorts and assess heterotypic reactivity to SARS-CoV-2.

Fisheries harvest has pervasive impacts on wild fish populations, including the truncation of size and age structures, altered population dynamics and density, and modified habitat and assemblage composition. Understanding the degree to which harvest-induced impacts increase the sensitivity of individuals, populations and ultimately species to environmental change is essential to ensuring sustainable fisheries management in a rapidly changing world. Here we generated multiple long-term (44-62 years), annually resolved, somatic growth chronologies of four commercially important fishes from New Zealand's coastal and shelf waters. We used these novel data to investigate how regional- and basin-scale environmental variability, in concert with fishing activity, affected individual somatic growth rates and the magnitude of spatial synchrony among stocks. Changes in somatic growth can affect individual fitness and a range of population and fishery metrics such as recruitment success, maturation schedules and stock biomass. Across all species, individual growth benefited from a fishing-induced release of density controls. For nearshore snapper and tarakihi, regional-scale wind and temperature also additively affected growth, indicating that future climate change-induced warming and potentially strengthened winds will initially promote the productivity of more poleward populations. Fishing increased the sensitivity of deep-water hoki and ling growth to the Interdecadal Pacific Oscillation (IPO). A forecast shift to a positive IPO phase, in concert with current harvest strategies, will likely promote individual hoki and ling growth. At the species level, historical fishing practices and IPO synergized to strengthen spatial synchrony in average growth between stocks separated by 400-600 nm of ocean. Increased spatial synchrony can, however, increase the vulnerability of stocks to deleterious stochastic events. Together, our individual- and species-level results show how fishing and environmental factors can conflate to initially promote individual growth but then possibly heighten the sensitivity of stocks to environmental change.

People with Cystic Fibrosis (CF) develop pulmonary inflammation, chronic infection and structural lung damage early in life, with these manifestations being prevalent among preschool children and infants. While early immune events are believed to play critical roles in shaping the progression, severity and disease burden later in life, T cells and their subsets are poorly studied in the CF lung, particularly during the formative early stages of disease.Using flow cytometry, we analyzed Mucosal Associated Invariant T (MAIT) cells, γδ T cells, and Natural Killer T (NKT)-like cells in bronchoalveolar lavage (BAL) samples from seventeen children with CF, aged two to six years old. The effect of age, sex and lung infections on the frequencies of these cells in BAL samples was analysed (grouped data were tested for normality and compared byNo difference was noted in the proportions of unconventional T cells related to the sex or age of the children. The frequency of γδ T cells and MAIT cells appeared unchanged by infection status. However, viral infections were associated with a significant increase in the proportion of NKT-like cells.By evaluating T cells in the lungs of children during the early formative stages of CF, this study identified potentially important interactions between these cells and viral pathogens.

Gastrokines (GKNs) are anti-inflammatory proteins secreted by gastric epithelial (surface mucous and pit) cells, with their aberrant loss of expression causally linked to premalignant inflammation and gastric cancer (GC). Transcriptional mechanisms accounting for GKN expression loss have not been elucidated. Using human clinical cohorts, mouse transgenics, bioinformatics, and transfection/reporter assays, we report a novel mechanism of GKN gene transcriptional regulation and its impairment in GC. GKN1/GKN2 loss is highly coordinated, with both genes showing parallel downregulation during human and mouse GC development, suggesting joint transcriptional control. In BAC transgenic studies, we defined a 152-kb genomic region surrounding the human GKN1/GKN2 genes sufficient to direct their tissue- and lineage-restricted expression. A screen of the 152-kb region for candidate regulatory elements identified a DNase I hypersensitive site (CR2) located 4 kb upstream of the GKN1 gene. CR2 showed overlapping enrichment of enhancer-related histone marks (H3K27Ac), a consensus binding site (GRE) for the glucocorticoid receptor (GR), strong GR occupancy in ChIP-seq data sets and, critically, exhibited dexamethasone-sensitive enhancer activity in reporter assays. Strikingly, GR showed progressive expression loss, paralleling that of GKN1/2, in human and mouse GC, suggesting desensitized glucocorticoid signaling as a mechanism underlying GKN loss. Finally, mouse adrenalectomy studies revealed a critical role for endogenous glucocorticoids in sustaining correct expression (and anti-inflammatory restraint) of GKNs in vivo. Together, these data link the coordinate expression of GKNs to a glucocorticoid-responsive and likely shared transcriptional enhancer mechanism, with its compromised activation contributing to dual GKN loss during GC progression.NEW & NOTEWORTHY Gastrokine 2 (GKN2) is an anti-inflammatory protein produced by the gastric epithelium. GKN2 expression is progressively lost during gastric cancer (GC), which is believed to play a casual role in GC development. Here, we use bacterial artificial chromosome transgenic studies to identify a glucocorticoid-responsive enhancer element that likely governs expression of GKN1/GKN2, which, via parallel expression loss of the anti-inflammatory glucocorticoid receptor, reveals a novel mechanism to explain the loss of GKN2 during GC pathogenesis.

We test the paradigm that in a future warmer ocean, shallower winter mixing will lead to less net primary production (NPP), by investigating whether warming between 2002 and 2018 led to changes in ...

Deployment of Deep Argo regional pilot arrays is underway as a step toward a global array of 1250 surface-to-bottom profiling floats embedded in the upper-ocean (2000 m) Argo Program. Of the 80 active Deep Argo floats as of July 2019, 55 are Deep Sounding Oceanographic Lagrangian Observer (SOLO) 6000-m instruments, and the rest are composed of three additional models profiling to either 4000 or 6000 m. Early success of the Deep SOLO is owed partly to its evolution from the Core Argo SOLO-II. Here, Deep SOLO design choices are described, including the spherical glass pressure housing, the hydraulics system, and the passive bottom detection system. Operation of Deep SOLO is flexible, with the mission parameters being adjustable from shore via Iridium communications. Long lifetime is a key element in sustaining a global array, and Deep SOLO combines a long battery life of over 200 cycles to 6000 m with robust operation and a low failure rate. The scientific value of Deep SOLO is illustrated, including examples of its ability (i) to observe large-scale spatial and temporal variability in deep ocean temperature and salinity, (ii) to sample newly formed water masses year-round and within a few meters of the sea floor, and (iii) to explore the poorly known abyssal velocity field and deep circulation of the World Ocean. Deep SOLO’s full-depth range and its potential for global coverage are critical attributes for complementing the Core Argo Program and achieving these objectives.

Expression of the cytokine IL-11 is elevated in human Helicobacter pylori infection and progressively increases with worsening gastric pathology. Additionally, IL-11 is required for tumor development in STAT3-dependent murine models of gastric cancer (GC) and, when administered acutely, causes resolving atrophic gastritis. However, it is unclear whether locally elevated IL-11 ligand expression can, in isolation from oncogenic gp130-JAK-STAT pathway mutations, initiate GC pathogenesis. Here we developed a transgenic mouse model of stomach-specific (keratin 19 promoter) IL-11 ligand overexpression. Keratin 19 promoter-IL-11 transgenic ( K19-IL11Tg) mice showed specific IL-11 overexpression in gastric corpus and antrum but not elsewhere in the gastrointestinal tract or in other tissues. K19-IL11Tg mice developed spontaneous premalignant disease of the gastric epithelium, progressing from atrophic gastritis to TFF2-positive metaplasia and severe epithelial hyperplasia, including adenoma-like lesions in a subset of older (1 yr old) animals. Although locally advanced, the hyperplastic lesions remained noninvasive. H. pylori infection in K19-IL11Tg mice accelerated some aspects of the premalignant phenotype. Finally, K19-IL11Tg mice had splenomegaly in association with elevated serum IL-11, with spleens showing an expanded myeloid compartment. Our results provide direct in vivo functional evidence that stomach-specific overexpression of IL-11, in isolation from germline gp130-JAK-STAT3 genetic drivers, is sufficient for premalignant progression. These findings have important functional implications for human GC, in which frequent IL-11 overexpression occurs in the reported absence of somatic mutations in gp130 signaling components. NEW & NOTEWORTHY We provide direct in vivo functional evidence that stomach-specific overexpression of the cytokine IL-11, in isolation from gp130-JAK-STAT3 pathway mutations, can trigger spontaneous atrophic gastritis progressing to locally advanced epithelial hyperplasia (but not dysplasia or carcinoma), which does not require, but may be accelerated by, concomitant Helicobacter pylori infection.

Ocean temperature changes around New Zealand are estimated from satellite sea surface temperature (SST) products since 1981, two high resolution expendable bathythermograph transects (HRXBT...

Cystic Fibrosis (CF) is primarily a progressive lung disease, characterized by chronic pulmonary infections with opportunistic pathogens. Such infections typically commence early in life, producing an inflammatory response marked by IL-8 chemokine production and neutrophilic infiltration, major contributory factors in CF progression. Studying this inflammation, especially early in life, is critical for developing new strategies for preventing or slowing disruption to the structural integrity of the CF airways. However, evaluating the immune responses of bronchoalveolar lavage (BAL) cells from children with CF faces technical challenges, including contamination carried from the lung due to pre-existing infections and low cell number availability. Here, we describe a technique for preparing BAL cells from young children with CF and using those cells in a bacterial stimulation assay. Initial antibiotic treatment proved essential for preventing resident bacteria from overgrowing BAL cell cultures, or non-specifically activating the cells. ACTB, identified as an optimal reference gene, was validated for accurate analysis of gene expression in these cells. Pseudomonas aeruginosa and Staphylococcus aureus were used as bacterial stimulants to evaluate the immune response of BAL cells from young children with CF. Addition of gentamicin prevented bacterial overgrowth, although if added after 3 hours of culture an extremely variable response resulted, with the bacteria causing a suppressive effect in some cultures. Addition of gentamicin after 1 hour of culture completely prevented this suppressive effect. This technique was then able to reproducibly measure the IL-8 response to stimulation with S. aureus and P. aeruginosa, including co-stimulation with both bacteria.

Children have mild severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) confirmed disease (COVID-19) compared to adults and the immunological mechanisms underlying this difference remain unclear. Here, we report acute and convalescent innate immune responses in 48 children and 70 adults infected with, or exposed to, SARS-CoV-2. We find clinically mild SARS-CoV-2 infection in children is characterised by reduced circulating subsets of monocytes (classical, intermediate, non-classical), dendritic cells and natural killer cells during the acute phase. In contrast, SARS-CoV-2-infected adults show reduced proportions of non-classical monocytes only. We also observe increased proportions of CD63+ activated neutrophils during the acute phase to SARS-CoV-2 in infected children. Children and adults exposed to SARS-CoV-2 but negative on PCR testing display increased proportions of low-density neutrophils that we observe up to 7 weeks post exposure. This study characterises the innate immune response during SARS-CoV-2 infection and household exposure in children., Childhood infection with SARS CoV2 is associated with a milder course of infection but the immunopathogenesis of this remains unclear. Here the authors explore immunological differences in the innate immune system during acute and convalescent SARS CoV2 infection in the young.

Compared to adults, children with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have predominantly mild or asymptomatic infections, but the underlying immunological differences remain unclear. Here, we describe clinical features, virology, longitudinal cellular, and cytokine immune profile, SARS-CoV-2-specific serology and salivary antibody responses in a family of two parents with PCR-confirmed symptomatic SARS-CoV-2 infection and their three children, who tested repeatedly SARS-CoV-2 PCR negative. Cellular immune profiles and cytokine responses of all children are similar to their parents at all timepoints. All family members have salivary anti-SARS-CoV-2 antibodies detected, predominantly IgA, that coincide with symptom resolution in 3 of 4 symptomatic members. Plasma from both parents and one child have IgG antibody against the S1 protein and virus-neutralizing activity detected. Using a systems serology approach, we demonstrate higher levels of SARS-CoV-2-specific antibody features of these family members compared to healthy controls. These data indicate that children can mount an immune response to SARS-CoV-2 without virological confirmation of infection, raising the possibility that immunity in children can prevent the establishment of SARS-CoV-2 infection. Relying on routine virological and serological testing may not identify exposed children, with implications for epidemiological and clinical studies across the life-span., Children with SARS-CoV-2 infection are more likely to have mild symptoms and may be asymptomatic, but underlying reasons remain unclear. Here, the authors show cellular, cytokine and antibody response to SARS-CoV-2 infection in three children who repeatedly tested negative for the virus by PCR, despite high exposure in the household.

Compared to adults, children with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have mild or asymptomatic infection, but the underlying immunological differences remain unclear. We describe clinical features, virology, longitudinal cellular and cytokine immune profile, SARS-CoV-2-specific serology and salivary antibody responses in a family of two parents with PCR-confirmed symptomatic SARS-CoV-2 infection and their three children, who were repeatedly SARS-CoV-2 PCR negative. Cellular immune profiles and cytokine responses of all children were similar to their parents at all timepoints. All family members had salivary anti-SARS-CoV-2 antibodies detected, predominantly IgA, that coincided with symptom resolution in 3 of 4 symptomatic members. Plasma from both parents and one child had IgG antibody detected against the S1 protein and virus neutralising activity ranging from just detectable to robust titers. Using a systems serology approach, we show that all family members demonstrated higher levels of SARS-CoV-2-specific antibody features than healthy controls. These data indicate that children can mount an immune response to SARS-CoV-2 without virological evidence of infection. This raises the possibility that despite chronic exposure, immunity in children prevents establishment of SARS-CoV-2 infection. Relying on routine virological and serological testing may therefore not identify exposed children, with implications for epidemiological and clinical studies across the life-span.

The cell surface mucin MUC1 is an important host factor limiting Helicobacter pylori (H. pylori) pathogenesis in both humans and mice by providing a protective barrier and modulating mucosal epithelial and leukocyte responses. The aim of this study was to establish the time-course of molecular events in MUC1-modulated gene expression profiles in response to H. pylori infection in wild type (WT) and MUC1-deficient mice using microarray-determined mRNA expression, gene network analysis and Ingenuity Pathway Analysis (IPA). A time-course over the first 72 h of infection showed significantly higher mucosal loads of bacteria at 8 h of infection in Muc1 -/- mice compared with WT, confirming its importance in the early stages of infection (P = 0.0003). Microarray analysis revealed 266 differentially expressed genes at one or more time-points over 72 h in the gastric mucosa of Muc1 -/- mice compared with WT control using a threshold of 2-fold change. The SPINK1 pancreatic cancer canonical pathway was strongly inhibited in Muc1 -/- mice compared with WT at sham and 8 h infection (P = 6.08E-14 and P = 2.25 E-19, respectively) but potently activated at 24 and 72 h post-infection (P = 1.38E-22 and P = 5.87E-13, respectively). The changes in this pathway are reflective of higher expression of genes mediating digestion and absorption of lipids, carbohydrates, and proteins at sham and 8 h infection in the absence of MUC1, but that this transcriptional signature is highly down regulated as infection progresses in the absence of MUC1. Uninfected Muc1 -/- gastric tissue was highly enriched for expression of factors involved in lipid metabolism and 8 h infection further activated this network compared with WT. As infection progressed, a network of antimicrobial and anti-inflammatory response genes was more highly activated in Muc1 -/- than WT mice. Key target genes identified by time-course microarrays were independently validated using RT-qPCR. These results highlight the dynamic interplay between the host and H. pylori, and the role of MUC1 in host defense, and provide a general picture of changes in cellular gene expression modulated by MUC1 in a time-dependent manner in response to H. pylori infection.

Background Helicobacter pylori occupy a unique niche, located within the mucus layer lining the stomach, and attached to the apical surface of the gastric epithelium. As such, antibodies would be expected to play a major role in regulating infection and/or pathogenesis. However, experiments using antibody-deficient mice to study gastric helicobacter infection have yielded inconsistent results, although some pointed toward antibodies increasing colonization levels and decreasing gastritis severity. The variability in these studies is possibly due to their use of nonmatched wild-type controls. This current study presents the first evaluation of the role of antibodies in H pylori infection by comparing antibody-deficient mice with matched wild-type siblings. Methods Matched wild-type and antibody-deficient μMT mice were generated by heterozygous crossings. In two separate experiments, appropriately genotyped sibling littermates were infected with H pylori for 4 months and then sera and stomachs were collected. Results There was no difference in H pylori colonization levels between infected μMT mice and sibling wild-type controls. Similarly, there was no significant difference in the severity of gastritis between these groups of mice, although there was a trend toward less severe gastritis in μMT mice which was supported by a significantly lower IFNγ (Th1) gastric cytokine response. Conclusions Comparing matched antibody-deficient and antibody-competent mice indicates that an antibody response does not influence H pylori colonization levels. Contrary to previous studies, these results suggest antibodies might have a minor pro-inflammatory effect by promoting gastric Th1 cytokines, although this did not translate to a significant effect on gastritis severity.

Several fast, narrow boundary currents flow along the eastern margin of New Zealand forming part of the western boundary current system of the South Pacific. In this study, using over 20 years of satellite altimeter observations and in situ data, we investigate the mean and variability of the current transports at seasonal, interannual and decadal time scales. We relate the means and fluctuations of the currents to the Southern Oscillation Index and to potential drivers of the circulation, including local and basin-scale winds. We also investigate the barotropic and baroclinic responses of the currents to basin-scale wind forcing using Rossby wave models. We find the currents are highly variable and there are no discernible trends in the transports since 1993. There is little coherence between transports along the boundary, suggesting a range of mechanisms drive the variability of the currents individually rather than the system as a whole. There is little correspondence between transports in any of the boundary currents and the El Nino/Southern Oscillation. We also find that the transports are not well described by the arrival of linear Rossby waves. At decadal time scales, only transports in the Subantarctic Front show a close correspondence with the variability of the wind stress curl averaged over the South Pacific. Seasonality is significant in two of the currents, likely driven by seasonality in local winds. In contrast with the larger East Australian Current, which forms part of the same South Pacific western boundary current system, we see collectively little evidence of a link between trends and variability in the New Zealand boundary currents and large-scale or local wind forcing.

The variability of Subtropical Mode Water (STMW) in the Southwest Pacific is investigated using a 28-year-long time series (1986 to 2014) of high-resolution expendable bathythermograph data north of New Zealand (PX06) and a shorter time series, the Roemmich-Gilson monthly Argo optimal interpolation for the 2004-2014 period. The variability in STMW inventories is compared to the variability in air-sea heat fluxes, mixed layer depths and transport of the East Auckland Current (EAUC) to assess both the atmospheric and oceanic roles influencing the formation and decay of STMW. The STMW north of New Zealand has a short lifespan with little persistence of the water mass from one year to the next one. Deeper mixed layers and negative anomalies in surface heat fluxes are correlated with increased formation of STMW. The heat content of the STMW layer is anticorrelated with inventories, particularly during the El Nino years. This suggests that large volumes of STMW are coincident with cooler conditions in the prior winter and less oceanic heat storage. There is significant seasonal and interannual variability in STMW inventories, however there are no trends in STMW properties, including its core layer temperature over the last decade. The variability of the winter EAUC transport is highly correlated with the STMW inventories and thermocline depth in the following spring, suggesting ocean dynamics deepen the thermocline and precondition for deeper mixed layers.

This paper investigates the mechanisms causing interannual variability of upper ocean heat content and sea surface temperature (SST) in the southwest Pacific. Using the ECCOv4 ocean reanalysis it is shown that air–sea heat flux and ocean heat transport convergence due to ocean dynamics both contribute to the variability of upper ocean temperatures around New Zealand. The ocean dynamics responsible for the ocean heat transport convergence are investigated. It is shown that SSTs are significantly correlated with the arrival of barotropic Rossby waves estimated from the South Pacific wind stress over the latitudes of New Zealand. Both Argo observations and the ECCOv4 reanalysis show deep isotherms fluctuate coherently around the country. The authors suggest that the depth of the thermocline around New Zealand adjusts to changes in the South Pacific winds, modifies the vertical advection of heat into the upper ocean, and contributes to the interannual variability of SST in the region.

β-Thalassemia is associated with several abnormalities of the innate immune system. Neutrophils in particular are defective, predisposing patients to life-threatening bacterial infections. The molecular and cellular mechanisms involved in impaired neutrophil function remain incompletely defined. We used the Hbbth3/+ β-thalassemia mouse and hemoglobin E (HbE)/β-thalassemia patients to investigate dysregulated neutrophil activity. Mature neutrophils from Hbbth3/+ mice displayed a significant reduction in chemotaxis, opsonophagocytosis, and production of reactive oxygen species, closely mimicking the defective immune functions observed in β-thalassemia patients. In Hbbth3/+ mice, the expression of neutrophil CXCR2, CD11b, and reduced NAD phosphate oxidase components (p22phox, p67phox, and gp91phox) were significantly reduced. Morphological analysis of Hbbth3/+ neutrophils showed that a large percentage of mature phenotype neutrophils (Ly6GhiLy6Clow) appeared as band form cells, and a striking expansion of immature (Ly6GlowLy6Clow) hyposegmented neutrophils, consisting mainly of myelocytes and metamyelocytes, was noted. Intriguingly, expression of an essential mediator of neutrophil terminal differentiation, the ets transcription factor PU.1, was significantly decreased in Hbbth3/+ neutrophils. In addition, in vivo infection with Streptococcus pneumoniae failed to induce PU.1 expression or upregulate neutrophil effector functions in Hbbth3/+ mice. Similar changes to neutrophil morphology and PU.1 expression were observed in splenectomized and nonsplenectomized HbE/β-thalassemia patients. This study provides a mechanistic insight into defective neutrophil maturation in β-thalassemia patients, which contributes to deficiencies in neutrophil effector functions.

Background Small-colony variants (SCVs) of Staphylococcus aureus are associated with worse lung disease in children with Cystic Fibrosis (CF), exhibit a higher resistance to antibiotics and co-colonize more commonly with Pseudomonas aeruginosa compared to the normal phenotype. The prevalence of SCVs in lower airway specimens from children with CF is largely unknown. Methods Each visible morphotype of S. aureus was subcultured onto horse blood agar (HBA) to enable identification of SCVs. Results Sixty-one samples from 41 children (mean age 11.7 (SD 5.3) years) were identified with a positive S. aureus culture from lower respiratory tract specimens collected in 2014-2015. None of the differing morphotypes isolated were identified as S. aureus SCVs. Conclusion In a center where anti staphylococcal prophylaxis is adopted, S. aureus SCVs were not isolated from the lower airways specimens in young children with CF indicating that acquisition of small colony variant S. aureus may not be a significant clinical problem in young children with CF.

The Argo Program has been implemented and sustained for almost two decades, as a global array of about 4000 profiling floats. Argo provides continuous observations of ocean temperature and salinity versus pressure, from the sea surface to 2000 dbar. The successful installation of the Argo array and its innovative data management system arose opportunistically from the combination of great scientific need and technological innovation. Through the data system, Argo provides fundamental physical observations with broad societally-valuable applications, built on the cost-efficient and robust technologies of autonomous profiling floats. Following recent advances in platform and sensor technologies, even greater opportunity exists now than 20 years ago to (i) improve Argo’s global coverage and value beyond the original design, (ii) extend Argo to span the full ocean depth, (iii) add biogeochemical sensors for improved understanding of oceanic cycles of carbon, nutrients, and ecosystems, and (iv) consider experimental sensors that might be included in the future, for example to document the spatial and temporal patterns of ocean mixing. For Core Argo and each of these enhancements, the past, present, and future progression along a path from experimental deployments to regional pilot arrays to global implementation is described. The objective is to create a fully global, top-to-bottom, dynamically complete, and multidisciplinary Argo Program that will integrate seamlessly with satellite and with other in situ elements of the Global Ocean Observing System (Legler et al., 2015). The integrated system will deliver operational reanalysis and forecasting capability, and assessment of the state and variability of the climate system with respect to physical, biogeochemical, and ecosystems parameters. It will enable basic research of unprecedented breadth and magnitude, and a wealth of ocean-education and outreach opportunities., Sí

Mucin 1 is a cell-membrane associated mucin, expressed on epithelial and immune cells that helps protect against pathogenic infections. In humans, MUC1 is highly polymorphic, predominantly due to the presence of a variable number tandem repeat (VNTR) region in the extracellular domain that results in MUC1 molecules of typically either short or long length. A genetic link is known between these MUC1 polymorphisms and inflammation-driven diseases, although the mechanism is not fully understood. We previously showed that MUC1 on murine macrophages specifically restricts activation of the NLRP3 inflammasome, thereby repressing inflammation. This study evaluated the effect of MUC1 VNTR polymorphisms on activity of the NLRP3 inflammasome in human macrophages, finding that long MUC1 alleles correlated with increased IL-1β production following NLRP3 inflammasome activation. This indicates that the length of MUC1 can influence IL-1β production, thus providing the first evidence of an immune-modulatory role of MUC1 VNTR polymorphisms in human macrophages.

MUC13 is a transmembrane mucin glycoprotein that is over produced by many cancers, although its functions are not fully understood. Nuclear factor-κB (NF-κB) is a key transcription factor promoting cancer cell survival, but therapeutically targeting this pathway has proved difficult because NF-κB has pleiotropic functions. Here, we report that MUC13 prevents colorectal cancer cell death by promoting two distinct pathways of NF-kB activation, consequently upregulating BCL-XL. MUC13 promoted tumor necrosis factor (TNF)-induced NF-κB activation by interacting with TNFR1 and the E3 ligase, cIAP1, to increase ubiquitination of RIPK1. MUC13 also promoted genotoxin-induced NF-κB activation by increasing phosphorylation of ATM and SUMOylation of NF-κB essential modulator. Moreover, elevated expression of cytoplasmic MUC13 and NF-κB correlated with colorectal cancer progression and metastases. Our demonstration that MUC13 enhances NF-κB signaling in response to both TNF and DNA-damaging agents provides a new molecular target for specific inhibition of NF-κB activation. As proof of principle, silencing MUC13 sensitized colorectal cancer cells to killing by cytotoxic drugs and inflammatory signals and abolished chemotherapy-induced enrichment of CD133+ CD44+ cancer stem cells, slowed xenograft growth in mice, and synergized with 5-fluourouracil to induce tumor regression. Therefore, these data indicate that combining chemotherapy and MUC13 antagonism could improve the treatment of metastatic cancers.

ASBTRACT Heat shock protein Complex (HspC) vaccines are composed of Hsp purified from pathogenic bacteria along with their chaperoned protein cargo. Mouse studies have shown that HspC vaccines can induce a strong immune response against pathogenic bacteria without addition of an exogenous adjuvant. These vaccines are now entering clinical trials. It was predicted, but not previously tested, that HspC vaccines induce an immune response due to the activation of Toll-Like Receptors (TLR) by their component Hsp. Recently we tested this supposition and found that while this held true for the cellular response to neisserial HspC vaccines, strong antigen-specific antibody responses were surprisingly generated in mice deficient in MyD88 and thus most TLR signaling. This suggested an unidentified mechanism by which HspC vaccines induce an antibody response. We have now examined the antigenic profile of this response and found no evidence that this is due to the induction of T-independent antibodies. Examination of the MyD88-dependent signaling pathways involved in the cellular response to neisserial HspC showed that both TRIF-dependent and TRIF-independent pathways are activated, each resulting in the secretion of different cytokines. Hence the mechanism of action of HspC vaccines is clearly more complicated than originally thought.

Multidecadal trends in ocean heat and freshwater content are well documented, but much less evidence exists of long-term changes in ocean circulation. Previously, a 12-yr increase, 1993 to 2004, in the circulation of the South Pacific Subtropical Gyre interior was described. That analysis was based on differences between early Argo and 1990s hydrographic data and changes in sea surface height. Here, it is shown that the trend of increasing circulation continues through 2014, with some differences within the Argo decade (2005 to 2014). Patterns that indicate or are consistent with increasing equatorward transport in the eastern portion of the South Pacific Gyre are seen in Argo temperature and steric height, Argo trajectory velocity, altimetric sea surface height, sea surface temperature, sea level pressure, and wind stress. Between 2005 and 2014 the geostrophic circulation across 35°S, from 160°W to South America, was enhanced by 5 Sv (1 Sv ≡ 106 m3 s−1) of added northward flow. This was countered by a southward transport anomaly between the date line and 160°W. Corresponding temperature trends span the full 2000-m depth range of Argo observations. The 22-yr trend, 1993 to 2014, in sea surface height at 35°S, 160°W is 8 cm decade−1. Trends in sea surface temperature over 34 yr, 1981 to 2014, show a similar spatial pattern to that of sea surface height, with an increase of 0.5°C decade−1 at 35°S, 160°W. These multidecadal trends support the interpretation of the 40°S maximum in global ocean heat gain as resulting from anomalous wind forcing and Ekman convergence.

MUC1 is a cell membrane-associated mucin, expressed ubiquitously on the mucosal epithelia as well as by immune cells, that limits the inflammatory response to multiple pathogens. We have recently shown that MUC1 controls inflammation resulting from Helicobacter pylori infection by suppressing interleukin-1β (IL-1β) produced via the NLRP3 inflammasome. Here, we demonstrate that MUC1 also regulates IL-1β secretion induced by the NLRP3-activating bacteria Haemophilus influenzae but not bacteria that activate other inflammasomes. Using purified ligands, we further demonstrate that MUC1 regulation of NLRP3 is specific, as it has no effect on the NLRP1b, NLRC4 and AIM2 inflammasomes. This indicates a unique role for MUC1 in the regulation of NLRP3-activating bacterial infections.

Background Neisseria meningitidis are common colonizers of the human nasopharynx. In some circumstances, N. meningitidis becomes an opportunistic pathogen that invades tissues and causes meningitis. While a vaccine against a number of serogroups has been in effective use for many years, a vaccine against N. meningitidis group B has not yet been universally adopted. Bacterial heat shock protein complex (HSPC) vaccines comprise bacterial HSPs, purified with their chaperoned protein cargo. HSPC vaccines use the intrinsic adjuvant activity of their HSP, thought to act via Toll-like receptors (TLR), to induce an immune response against their cargo antigens. This study evaluated HSPC vaccines from N. meningitidis and the closely related commensal N. lactamica . Results The protein composition of N. lactamica and N. meningitidis HSPCs were similar. Using human HEK293 cells we found that both HSPCs can induce an innate immune response via activation of TLR2. However, stimulation of TLR2 or TLR4 deficient murine splenocytes revealed that HSPCs can activate an innate immune response via multiple receptors. Vaccination of wildtype mice with the Neisseria HSPC induced a strong antibody response and a Th1-restricted T helper response. However, vaccination of mice deficient in the major TLR adaptor protein, MyD88, revealed that while the Th1 response to Neisseria HSPC requires MyD88, these vaccines unexpectedly induced an antigen-specific antibody response via a MyD88-independent mechanism. Conclusions N. lactamica and N. meningitidis HSPC vaccines both have potential utility for immunising against neisserial meningitis without the requirement for an exogenous adjuvant. The mode of action of these vaccines is highly complex, with HSPCs inducing immune responses via both MyD88-dependent and -independent mechanisms. In particular, these HSPC vaccines induced an antibody response without detectable T cell help.