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Lisbon's historical seismicity, socioeconomic importance and population density contribute to a moderate to high seismic risk. The geological setting of the city includes cases of inclined layers, interbedding sedimentary rock layers in soil deposits, sand and clay layers in the same geological unit, leading to cases of shear wave velocity inversion and a large scatter of geotechnical properties within each geological unit. The morphological setting of the city is characterised by the existence of several hills and relatively shallow, stream-carved valleys filled with alluvial deposits. The seismic site effects in Lisbon were assessed through numerical simulation using the linear equivalent method and adopting the two types of seismic action defined in the Portuguese National Annex of Eurocode 8: (i) one-dimensional subsoil models covering the city, at sites where borehole data and geophysical data were available; (ii) two-dimensional subsoil models along three cross-sections representative of the geological settings and morphology. The distribution of amplification factors in the city revealed a pattern related to ground characteristics that impact seismic soil response, such as the presence of high-thickness cover deposits, significant shear-wave variations, alluvial valleys, a crest or significant slope variations and inclined layers. The 2D/1D spectral ratio highlighted the areas were 2D seismic effects are more important. The soil factor determined in the numerical analyses was consistently greater than the soil factor values indicated in Eurocode 8. [ABSTRACT FROM AUTHOR]

Background: CD6 is one of many cell surface receptors known to regulate signal transduction upon T cell activation. However, whether CD6 mediates costimulatory or inhibitory signals is controversial. When T cells engage with antigen presenting cells (APCs), CD6 interacts with its ligand CD166 at the cell–cell interface while the cytosolic tail assembles a complex signalosome composed of adaptors and effector enzymes, that may either trigger activating signaling cascades, or instead modulate the intensity of signaling. Except for a few cytosolic adaptors that connect different components of the CD6 signalosome, very little is known about the mechanistic effects of the cytosolic effectors that bind CD6. Methods: Jurkat model T cells were transfected to express wild-type (WT) CD6, or a cytoplasmic truncation, signaling-disabled mutant, CD6Δcyt. The two resulting cell lines were directly activated by superantigen (sAg)-loaded Raji cells, used as APCs, to assess the net signaling function of CD6. The Jurkat cell lines were further adapted to express a FRET-based unimolecular HRas biosensor that reported the activity of this crucial GTPase at the immunological synapse. Results: We show that deletion of the cytosolic tail of CD6 enhances T-cell responses, indicating that CD6 restrains T-cell activation. One component of the CD6-associated inhibitory apparatus was found to be the GTPase activating protein of Ras (RasGAP), that we show to associate with CD6 in a phosphorylation-dependent manner. The FRET HRas biosensor that we developed was demonstrated to be functional and reporting the activation of the T cell lines. This allowed to determine that the presence of the cytosolic tail of CD6 results in the down-regulation of HRas activity at the immunological synapse, implicating this fundamental GTPase as one of the targets inhibited by CD6. Conclusions: This study provides the first description of a mechanistic sequence of events underlying the CD6-mediated inhibition of T-cell activation, involving the modulation of the MAPK pathway at several steps, starting with the coupling of RasGAP to the CD6 signalosome, the repression of the activity of Ras, and culminating in the reduction of ERK1/2 phosphorylation and of the expression of the T-cell activation markers CD69 and IL-2R α chain. 9f2SuWv7Lo8KDpPx-hd1D5 Video abstract [ABSTRACT FROM AUTHOR]

Summary: The characterization of the architecture, structure and extracellular interactions of the CD6 glycoprotein, a transmembrane receptor expressed in medullary thymocytes and all mature T‐cell populations, has been enhanced by the existence of monoclonal antibodies (mAbs) that specifically recognize the various scavenger receptor cysteine‐rich (SRCR) domains of the ectodomain. Using engineered isoforms of CD6 including or excluding each of the three SRCR domains, either expressed at the membranes of cells or in soluble forms, we provide conclusive and definitive evidence that domain 2 of CD6, previously not identifiable, can be recognized by the CD6 mAbs OX125 and OX126, and that OX124 targets domain 3 and can block the interaction at the cell surface of CD6 with its major ligand CD166. Alternative splicing‐dependent CD6 isoforms can now be confidently identified. We confirm that following T‐cell activation there is a partial replacement of full‐length CD6 by the CD6Δd3 isoform, which lacks the CD166‐binding domain, and we find no evidence for the expression of other CD6 isoforms at the mRNA or protein levels. [ABSTRACT FROM AUTHOR]

Introduction and aims: Splenic marginal zone lymphoma, an uncommon subtype of non-Hodgkin lymphoma (NHL), is usually present with symptomatic splenomegaly. Although splenectomy has long been considered the first-line therapy in symptomatic or cytopenic patients, it can lead to significant morbidity and mortality. Splenic irradiation is an option for patients who have a poor response to systemic therapy and/or are not surgical candidates. In this paper, we present a case report of a patient who received splenic radiotherapy for symptomatic splenomegaly. Methods: An 85-year-old Caucasian man with a 4 year history of low-grade NHL presented with progressive pancytopenia, significant weight loss and symptomatic splenomegaly (abdominal discomfort, sense of fullness and limitation of mobility due to spleen size). The patient refused splenectomy and, in December 2017, was referred to palliative splenic radiotherapy. He was initially treated with five fractions of one Grey (Gy) in order to evaluate clinical and haematology response. After that, 1.5 Gy daily, 5 days a week for 3 weeks. 3D conformal radiotherapy, multiple fields and mixed energy (6 and 15 Mv) were used. Results: Radiotherapy allowed significant splenic reduction to almost half the size, resolving abdominal discomfort and improving quality of life. There was no decline of haemoglobin, leukocytes and platelet counts; in fact, there was a marginal increase. Conclusion: Palliative splenic irradiation was well tolerated confirming that it is a safe treatment option for palliation of symptomatic splenomegaly. Thereby, splenic irradiation should be strongly considered in the management of symptomatic splenomegaly, for selected patients who are refractory to or unsuitable for other options or when the patient refuses other treatments. [ABSTRACT FROM AUTHOR]

Lisbon has been affected by several moderate to strong earthquakes that caused considerable damage and produced significant economic and social impacts (e.g., the November 1st, 1755, earthquake). Studies on the potential damage due to a seismic event have been done considering Lisbon's moderate to high seismic hazard, but the seismic site effects have not yet been investigated at the city scale. The local ground conditions can locally modify the characteristics of surface seismic motion. Based on a multidisciplinary dataset composed of surface geology, a geotechnical database, and a geophysical database that compiles all the available geophysical tests carried out in Lisbon, an integrated approach to seismic ground characterisation was performed. A regression analysis of the shear-wave velocity values compiled in the geophysical database was done for each geological unit. The peak frequency distribution in the city, assessed from the ambient vibration measurements, showed a pattern in peak frequency variation. It decreases from the oldest to the most recent geological formations that outcrop in the SW-NE direction. Three zones based on peak frequency value distribution were proposed. An estimation of the impedance contrast depths was computed through two processes, considering the previous results: (i) the shallower contrast depth was assessed through a sharp variation of NSPT values available in the geotechnical database, and (ii) the deeper contrast depth was estimated based on geology data and deep borehole information. The results showed that for the upper ∼100 m of depth, a consistent relationship between the contrasts identified through different data was obtained, even if uncertainty increased with depth. • A multidisciplinary dataset-based contribution to seismic microzonation. • V S -depth equations defined for each geological formation. • Peak frequency distribution at the city scale. • Impedance contrast depth map based on an integrated approach. • Consistent relationship between the contrasts identified through different data. [ABSTRACT FROM AUTHOR]

In palliative care, drugs are considered futile if they do not have a short-term benefit in symptom control or quality of life. The authors examined pharmacotherapy prescribed for patients referred to palliative care to identify futile drugs. This was a retrospective analysis of patients referred over 6 months, focusing on the prescription of gastric protectants, antidiabetic agents, bisphosphonates, anticoagulants, antidementia drugs, statins, and antihypertensive agents. The sample consisted of 448 patients. Gastric protectants were prescribed futilely in 50% of cases (125/248), statins in 97% (69/71), antihypertensive agents in 27% (42/155), antidiabetic drugs in 1% (1/70), bisphosphonates in 27% (4/15), and antidementia drugs in 100% (9/9). This study reveals that many patients with advanced cancer continue to be treated with inappropriate drugs and points to the need for medical training in palliative care, drawing attention to the need for therapeutic review at each medical visit. [ABSTRACT FROM AUTHOR]

Promoting a more transparent, clearer and more effective communication between citizens, scientists and policy-makers has been a priority goal of the European Commission and other institutions in recent years. Science communication matters for the extent to which citizens may be more or less available to participate and to get involved in the debate and in the regulatory process related to scientifictechnological developments thus helping guarantee the quality of scientific results and the democratization of decisions. In the last two decades, the concept of Public Engagement with Science and Technology (PEST) has become central to analyses of the relation between citizens and technoscience. However, its meaning is not always clear as there are ambiguities and divergences between different sources. This article aims to map the views of different scholars, and to contribute to a clearer understanding of the concept of PEST and its implications. Further to discussing different understandings of PEST's objectives, the article evaluates the way in which the concept has been used in Portugal through an analysis of legal texts and of the mission and goals of research and higher education institutions. We conclude that instrumental arguments still prevail in the normative discourses that frame the Portuguese scientific activity. [ABSTRACT FROM AUTHOR]

Glyceraldehyde 3-phosphate dehydrogenases (GAPDH) are cytoplasmic glycolytic enzymes that, despite lacking identifiable secretion signals, have been detected at the surface of several prokaryotic and eukaryotic organisms where they exhibit non-glycolytic functions including adhesion to host components. Group B Streptococcus (GBS) is a human commensal bacterium that has the capacity to cause life-threatening meningitis and septicemia in newborns. Electron microscopy and fluorescence-activated cell sorter (FACS) analysis demonstrated the surface localization of GAPDH in GBS. By addressing the question of GAPDH export to the cell surface of GBS strain NEM316 and isogenic mutant derivatives of our collection, we found that impaired GAPDH presence in the surface and supernatant of GBS was associated with a lower level of bacterial lysis. We also found that following GBS lysis, GAPDH can associate to the surface of many living bacteria. Finally, we provide evidence for a novel function of the secreted GAPDH as an inducer of apoptosis of murine macrophages. [ABSTRACT FROM AUTHOR]

Abstract: The present work reports the values of the gaseous standard (p ∘ =0.1MPa) molar enthalpies of formation of the three acetylpyridine isomers, at T =298.15K. For each isomer, that value was derived from measurements of the standard molar energy of combustion of the corresponding liquid, using a static bomb calorimeter, together with measurements of the standard molar enthalpy of vaporization, measured by Calvet microcalorimetry. [Copyright &y& Elsevier]

Historically, Portugal has suffered the effects of several strong earthquakes. In particular, Lisbon and the south and southwestern Portuguese coast were affected by the largest known European earthquake on November 1st, 1755. It is well known that the local ground conditions strongly affect the seismic ground motion, modifying the signal's amplitude, duration, and frequency content, which induces large variability in the motion induced to buildings and infrastructures. Aware of this situation, the Lisbon Municipality promoted the development of a project to elaborate a new seismic microzonation map, based on a large geotechnical database and geological data. The Eurocode 8 ground classification based on the V S30 parameter was adopted as reference. However, the geotechnical database has a very small number of geophysical logs and is mainly composed of borehole data and SPT blows number. An expedited methodology was applied to determine the N 30 parameter, as a proxy of the V S30 parameter. Non-invasive field experiments (surface waves seismic profiles and HVSR performed with ambient vibrations) and data collected from independent geophysical reports were also used to check and validate the classification based on N 30. Because the distribution of the classified profiles was not uniformly distributed, the final microzonation map was obtained from the combination of the profile classification and the surface geology. • Seismic microzonation map based on large geotechnical database. • Automatic algorithm to classify each profile based on a proxy of V S30 EC8 ground classification. • The final zonation joins the profile classification with geological data. [ABSTRACT FROM AUTHOR]

Background: T-cell membrane scaffold proteins are pivotal in T cell function, acting as versatile signaling hubs. While CD6 forms a large intracellular signalosome, it is distinguished from typical scaffolds like LAT or PAG by possessing a substantial ectodomain that binds CD166, a well-characterized ligand expressed on most antigen-presenting cells (APC), through the third domain (d3) of the extracellular region. Although the intact form of CD6 is the most abundant in T cells, an isoform lacking d3 (CD6∆d3) is transiently expressed on activated T cells. Still, the precise character of the signaling transduced by CD6, whether costimulatory or inhibitory, and the influence of its ectodomain on these activities are unclear. Methods: We expressed CD6 variants with extracellular deletions or cytosolic mutations in Jurkat cells containing eGFP reporters for NF-κB and NF-AT transcription factor activation. Cell activation was assessed by eGFP flow cytometry following Jurkat cell engagement with superantigen-presenting Raji cells. Using imaging flow cytometry, we evaluated the impact of the CD6-CD166 pair on cell adhesiveness during the antigen-dependent and -independent priming of T cells. We also examined the role of extracellular or cytosolic sequences on CD6 translocation to the immunological synapse, using immunofluorescence-based imaging. Results: Our investigation dissecting the functions of the extracellular and cytosolic regions of CD6 revealed that CD6 was trafficked to the immunological synapse and exerted tonic inhibition wholly dependent on its cytosolic tail. Surprisingly, however, translocation to the synapse occurred independently of the extracellular d3 and of engagement to CD166. On the other hand, CD6 binding to CD166 significantly increased T cell:APC adhesion. However, this activity was most evident in the absence of APC priming with superantigen, and thus, in the absence of TCR engagement. Conclusions: Our study identifies CD6 as a novel 'on/off' scaffold-receptor capable of modulating responsiveness in two ways. Firstly, and independently of ligand binding, it establishes signaling thresholds through tonic inhibition, functioning as a membrane-bound scaffold. Secondly, CD6 has the capacity for alternative splicing-dependent variable ligand engagement, modulating its checkpoint-like activity. [ABSTRACT FROM AUTHOR]

Body temperature changes in laboratory mice are often assessed by invasive and stressful methods, which may confound the measurement. Infrared thermography is a possible non-invasive alternative, but the cost of standard thermal cameras, lack of dedicated software for biomedical purposes, and labour-intensiveness of thermal image analysis have limited their use. An additional limitation lies on the scarcity of research on the causing factors of differences between body surface and core body temperature. We propose a method for automatic assessment of mean body surface temperature in freely-moving mice, using dedicated software for thermal image analysis. While skin surface temperature may not necessarily be linearly correlated with core body temperature (in itself an imprecise concept), under standardized environmental conditions, such as those in which laboratory animals are kept, mean body surface temperature can provide useful information on their thermal status (i.e. deviations from normothermia, namely hypo- and hyperthermia). We developed a publicly available software that includes an imaging analysis workflow/algorithm for automatic segmentation of the pixels associated with the animal from the pixels associated with the background, removing the need for manually defining the area of analysis. A batch analysis mode is also available, for automatic and high-throughput analysis of all image files located in a folder. The software is compatible with the most widespread thermal camera manufacturer, 'FLIR Systems', as well as with the low-cost 'Thermal Expert TE-Q1' miniaturized high-resolution thermal camera used for this study. Furthermore, the software has been validated in a mouse model expressing non-transient hypothermia, where the thermal analysis results were compared with readings from implanted thermo-sensitive passive integrated transponders tags. Thermography allows for thermal assessment of laboratory animals without the effect of handling stress on their physiology or behaviour. Our automatic image analysis software also removes observer errors and bias, while speeding up the data processing. • Body temperature variation gives valuable information on animal health and welfare • Thermal assessment of laboratory animals raises technical and welfare challenges • IR thermography is an option, but analysis is laborious and prone to variability • We propose a novel user-friendly software for analysis of thermal images of mice • The new analysis methodology was validated in LPS-injected mice showing hypothermia [ABSTRACT FROM AUTHOR]

Background Drowning is the third leading cause of death worldwide (WHO, 2010). According to Brenner et al (2009) participating in swimming lessons (SL) can reduce by 88% the risk of drowning in children 1-4 years old, despite some controversy regarding the most appropriate swimming programs (Ward, 2009). On the other hand no studies tested the skills acquired in SL in drowning prevention. So we proposed a test to evaluate the survivability of a child that accidentally falls into the water. Methods Twenty two children (4.68±0.82yrs) who practice SL (2.01±0.91yrs/practice) were subjected to two tests: aquatic readiness (AR) (Stallman et al, 2008); and survival test (ST), which consisted of an inflatable boat ride (unknown pool; presence of the usual swim teacher; wearing t-shirt) which 'accidentally' turns. Recorded images were later observed by 6 field experts whose observations obtained an overall index of concordance (IC) of 89%. Results In ST 15 children had positive responses (n=10, 100% IC; n=1, 66% IC; n=1, 83% IC; n=3, 50% IC) and 7 (n=6, 100% IC; n=1, 66% IC) would be in danger. Conclusions Through this test, we found that not all children whose result was positive in AR had a positive performance in the ST. This brings us to observe according to Langendörfer (2011) that the positive or negative response of the subject depends on the interaction of various constraints such as individual characteristics, the environment conditions, and the state in which the swimmer is. The application of ST suggests that the inclusion of safety and prevention activities in swimming lessons, aiming to develop attitudes and motor skills as a defense to drowning, must be taken into account. More studies are necessary to provide valid information to assist pediatricians in advising parents regarding what type of SL are more appropriate to reduce drowning. [ABSTRACT FROM AUTHOR]

Objective Orolingual angioedema (OA) is a well known early complication of treatment with alteplase in ischemic stroke patients. Our aim was to study risk factors for OA in these patients, namely insular cortex ischemia. Methods Retrospective case-cohort study using the prospective registry of all consecutive ischemic stroke patients submitted to intravenous thrombolysis with alteplase. Clinical data was retrieved from the registry and medical records. Two independent observers evaluated early signs of insular cortex ischemia on pre-thrombolysis computed tomography (CT) and of insular cortex infarct on early follow-up imaging. Univariate and multivariate analysis were performed to identify predictors of OA. Results Of the 659 patients with acute ischemic stroke treated with alteplase, 32 developed OA (4.9%, 95%CI = 3.3–6.6). Frequency of early signs of insular cortex ischemia on pre-thrombolysis CT and of insular cortex infarct on follow-up imaging was similar in patients with and without OA ( p = 0.241 and p = 0.145, respectively). The only independent predictors of OA occurrence were female sex (OR = 5.47, 95%CI = 1.98–15.10) and angiotensin-converting enzyme inhibitor (ACE-I) use (OR = 3.87, 95%CI = 1.71–8.75). Conclusions Female sex and ACE-I use are independent risk factors for OA occurrence in ischemic stroke patients treated with alteplase. Early signs of insular cortex ischemia on pre-thrombolysis CT were not significantly associated with OA. [ABSTRACT FROM AUTHOR]

Background Chronic heart failure is a complex syndrome manifested by hemodynamic disturbances, exercise intolerance, increased mortality and reduced quality of life (Heidenreich et al., 2006). Besides impaired cardiac function, a variety of changes in peripheral skeletal muscles may contribute to the major and debilitating symptoms of chronic heart failure, dyspnea and fatigue (Coats et al., 1994). The aim of this study was to evaluate the perception of quality of life and physical performance in patients with heart failure. Methods A total of 47 patients, of both genders, with chronic heart failure, were recruited (55,5±12,3 years), and divided into two groups. One group (n=28) clinical and another group (n=19) surgical. Fifty five percent of the patients had NYHA class III and forty five percent NYHA class III. Quality of life was assessed, in both groups, with the Minnesota Living with Heart Failure Questionnaire (Rector et al; 1992). The physical activity level was measured by an accelerometer (number of steps) during seven consecutive days. Results For the quality of life, were found significant differences (p≤0.05), in the physical dimensions of chronic heart failure patients. The surgical group showed a better quality of life. Considering the physical activity, the clinical group appear with better performance (p≤0,01). In the daily activities, there weren't observed vigorous or very vigorous intensity activities. Conclusions These results indicate that chronic heart failure patients differ in their daily physical activity, especially in high-impact activities, due to age, gender, and disease progression (Rector, 2005). Further investigation should be directed towards the impact of the different components of the rehabilitation process upon quality of live improvement in patients with chronic heart failure. [ABSTRACT FROM AUTHOR]

Group B Streptococcus (GBS), a commensal organism, can turn into a life-threatening pathogen in neonates and elderly, or in adults with severe underlying diseases such as diabetes. We developed a vaccine targeting the GBS glyceraldehyde-3-phosphate dehydrogenase (GAPDH), a glycolytic enzyme detected at the bacterial surface, which was proven to be effective in a neonatal mouse model of infection. Since this bacterium has emerged as an important pathogen in non-pregnant adults, here we investigated whether this vaccine also confers protection in an adult susceptible and in a diabetic mouse model of infection. For immunoprotection studies, sham or immunized adult mice were infected with GBS serotype Ia and V strains, the two most prevalent serotypes isolated in adults. Sham and vaccinated mice were also rendered diabetic and infected with a serotype V GBS strain. For toxicological (pre-clinical) studies, adult mice were vaccinated three times, with three concentrations of recombinant GAPDH adjuvanted with Allydrogel, and the toxicity parameters were evaluated twenty-four hours after the last immunization. For the stability tests, the vaccine formulations were maintained at 4°C for 6 and 12 months prior immunization. The results showed that all tested doses of the vaccine, including the stability study formulations, were immunogenic and that the vaccine was innocuous. The organs (brain, blood, heart, and liver) of vaccinated susceptible or diabetic adult mice were significantly less colonized compared to those of control mice. Altogether, these results demonstrate that the GAPDH-based vaccine is safe and stable and protects susceptible and diabetic adult mice against GBS infections. It is therefore a promising candidate as a global vaccine to prevent GBS-induced neonatal and adult diseases. [ABSTRACT FROM AUTHOR]

Streptococcus agalactiae (or Group B Streptococcus, GBS) is a commensal bacterium present in the intestinal and urinary tracts of approximately 30% of humans. We and others previously showed that the PI-2a pilus polymers, made of the backbone pilin PilB, the tip adhesin PilA and the cell wall anchor protein PilC, promote adhesion to host epithelia and biofilm formation. Affinity-purified PI-2a pili from GBS strain NEM316 were recognized by N-acetylneuraminic acid (NeuNAc, also known as sialic acid) specific lectins such as Elderberry Bark Lectin (EBL) suggesting that pili are sialylated. Glycan profiling with twenty different lectins combined with monosaccharide composition by HPLC suggested that affinity-purified PI-2a pili are modified by N-glycosylation and decorated with sialic acid attached to terminal galactose. Analysis of various relevant mutants in the PI-2a pilus operon by flow-cytometry and electron microscopy analyses pointed to PilA as the pilus subunit modified by glycosylation. Double labeling using PilB antibody and EBL lectin, which specifically recognizes N-acetylneuraminic acid attached to galactose in α-2, 6, revealed a characteristic binding of EBL at the tip of the pilus structures, highly reminiscent of PilA localization. Expression of a secreted form of PilA using an inducible promoter showed that this recombinant PilA binds specifically to EBL lectin when produced in the native GBS context. In silico search for potentially glycosylated asparagine residues in PilA sequence pointed to N427 and N597, which appear conserved and exposed in the close homolog RrgA from S. pneumoniae, as likely candidates. Conversion of these two asparagyl residues to glutamyl resulted in a higher instability of PilA. Our results provide the first evidence that the tip PilA adhesin can be glycosylated, and suggest that this modification is critical for PilA stability and may potentially influence interactions with the host. [ABSTRACT FROM AUTHOR]

In the present work, the knowledge on target proteins of standard antibiotics was extended to antimicrobial mushroom compounds. Docking studies were performed for 34 compounds in order to evaluate their affinity to bacterial proteins that are known targets for some antibiotics with different mechanism of action: inhibitors of cell wall synthesis, inhibitors of protein synthesis, inhibitors of nucleic acids synthesis and antimetabolites. After validation of the molecular docking approach, virtual screening of all the compounds was performed against penicillin binding protein 1a (PBP1a), alanine racemase (Alr), D-alanyl-D-alanine synthetase (Ddl), isoleucyl-tRNA sinthetase (IARS), DNA gyrase subunit B, topoisomerase IV (TopoIV), dihydropteroate synthetase (DHPS) and dihydrofolate reductase (DHFR) using AutoDock4. Overall, it seems that for the selected mushroom compounds (namely, enokipodins, ganomycins and austrocortiluteins) the main mechanism of the action is the inhibition of cell wall synthesis, being Alr and Ddl probable protein targets. [ABSTRACT FROM AUTHOR]

Sepsis is the third most common cause of neonatal death, with Group B Streptococcus (GBS) being the leading bacterial agent. The pathogenesis of neonatal septicemia is still unsolved. We described previously that host susceptibility to GBS infection is due to early IL-10 production. In this study, we investigated whether triggering TLR2 to produce IL-10 is a risk factor for neonatal bacterial sepsis. We observed that, in contrast to wild-type (WT) pups, neonatal TLR2-deficient mice were resistant to GBSinduced sepsis. Moreover, if IL-10 signaling were blocked in WT mice, they also were resistant to sepsis. This increased survival rate was due to an efficient recruitment of neutrophils to infected tissues that leads to bacterial clearance, thus preventing the development of sepsis. To confirm that IL-10 produced through TLR2 activation prevents neutrophil recruitment, WT pups were treated with the TLR2 agonist Pam3CSK4 prior to nebulization with the neutrophil chemotactic agent LTB4. Neutrophil recruitment into the neonatal lungs was inhibited in pups treated with Pam3CSK4. However, the migration was restored in Pam3CSK4- treated pups when IL-10 signaling was blocked (either by anti-IL-10R mAb treatment or by using IL-10-deficient mice). Our findings highlight that TLR2-induced IL-10 production is a key event in neonatal susceptibility to bacterial sepsis. [ABSTRACT FROM AUTHOR]

Group B Streptococcus (GBS) is the leading cause of neonatal pneumonia, septicemia, and meningitis. We have previously shown that in adult mice GBS glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is an extracellular virulence factor that induces production of the immunosuppressive cytokine interleukin-10 (IL-10) by the host early upon bacterial infection. Here, we investigate whether immunity to neonatal GBS infection could be achieved through maternal vaccination against bacterial GAPDH. Female BALB/c mice were immunized with rGAPDH and the progeny was infected with a lethal inoculum of GBS strains. Neonatal mice born from mothers immunized with rGAPDH were protected against infection with GBS strains, including the ST-17 highly virulent clone. A similar protective effect was observed in newborns passively immunized with anti-rGAPDH IgG antibodies, or F(ab')2 fragments, indicating that protection achieved with rGAPDH vaccination is independent of opsonophagocytic killing of bacteria. Protection against lethal GBS infection through rGAPDH maternal vaccination was due to neutralization of IL-10 production soon after infection. Consequently, IL-10 deficient (IL-10-/- ) mice pups were as resistant to GBS infection as pups born from vaccinated mothers. We observed that protection was correlated with increased neutrophil trafficking to infected organs. Thus, anti-rGAPDH or anti-IL-10R treatment of mice pups before GBS infection resulted in increased neutrophil numbers and lower bacterial load in infected organs, as compared to newborn mice treated with the respective control antibodies. We showed that mothers immunized with rGAPDH produce neutralizing antibodies that are sufficient to decrease IL-10 production and induce neutrophil recruitment into infected tissues in newborn mice. These results uncover a novel mechanism for GBS virulence in a neonatal host that could be neutralized by vaccination or immunotherapy. As GBS GAPDH is a structurally conserved enzyme that is metabolically essential for bacterial growth in media containing glucose as the sole carbon source (i.e., the blood), this protein constitutes a powerful candidate for the development of a human vaccine against this pathogen. [ABSTRACT FROM AUTHOR]