Innate Immune Responses to Plasmodium Parasites

Bisher gibt es keine effektive Impfung gegen Malaria und der beste immunologische Schutz wird durch wiederholte intravenöse Injektion von nicht-vermehrungsfähigen Sporozoiten erreicht. Im Gegensatz dazu bietet die Infektion im Blutstadium nur eine Teilimmunität gegen schwere Verläufe der Krankheit. Um beide Prozesse besser zu verstehen, ist eine tiefgehende Untersuchung der Reaktion des angeborenen Immunsystems auf Sporozoiten, sowie Parasiten im Blutstadium erforderlich. Erkenntnisse hieraus können dabei helfen, die Überlegenheit des Sporozoiten-Impfstoffs zu verstehen und, letztendlich, seine Wirksamkeit in einem sichereren, kostengünstigeren und skalierbaren Impfstoff zu rekapitulieren. Um sterile Sporozoiten aus Mückenprärationen für in-vitro experimente zu gewinnen, wurden die Parasiten FACS sortiert und anschließend mit Makrophagen co-kultivert. RNA Sequenzierung der Makrophagen, zeigte ein von Sporozoiten induziertes Expressionsprofil, das durch die Expression von inflammatorischen Genen gekennzeichnet ist. Insbesondere CD201 wurde auf Makrophagen stark hochreguliert und könnte eine Rolle bei der gamma-delta T-Zell-Aktivierung spielen. Darüber hinaus kann gezeigt werden, dass die Aktivierung von Makrophagen durch Sporozoiten teilweise von TLR2 und MyD88 abhängig ist. Interessanterweise waren die genetischen Signaturen „Reaktion auf Verwundung" und „Makroautophagie" in Makrophagen überrepräsentiert die mit Sporozoiten co-kultiviert wurden und sind wahrscheinlich Folgen von aktiver Sporozoiten-Traversierung durch Makrophagen. In der Tat zeigten Mäuse, die mit Traversierungs-defizienten Sporozoiten geimpft wurden stark reduzierte CD8 T-Zell Antworten. Dies deutet auf eine mögliche Rolle der Zelltraversion bei der Induktion effektiver adaptiver Immunantworten hin. Insgesamt tragen diese Ergebnisse zu dem Verständnis der angeborenen Immunantwort auf Plasmodium-Parasiten bei und bieten weitere Möglichkeiten zur zukünftigen Forschung.Effective vaccination against malaria remains a critical element in the effort to eradicate the disease. So far, best protection is induced by repeated intravenous injection of irradiated, non-replicating sporozoites. In contrast, blood stage infection only affords semi-immunity after several disease episodes are endured. Therefore, in-depth analyses of innate immune responses to sporozoite and blood stage parasites are needed to understand the superiority of the attenuated sporozoite vaccine and ultimately, to recapitulate its efficacy in a safer, cheaper and more practical vaccine. To probe sporozoite-induced innate cell activation, parasites were flow sorted from salivary gland extracts. In a reductionist system, sorted P. berghei sporozoites were co-cultured with primary mouse macrophages. Transcriptomic analysis of sporozoite-experienced macrophages revealed a distinct expression profile characterized by NF-κB driven expression of inflammatory mediators. In particular, CD201, a CD1d-like transmembrane receptor with lipid presentation capabilities, was strongly upregulated on macrophages and might play a role in gamma-delta T-cell activation. In addition, first evidence is provided that macrophage activation by sporozoites is partly dependent on TLR2 and MyD88. Intriguingly, ‘response to wounding’ and ‘macroautophagy’ signatures were enriched in sporozoite-stimulated macrophages and are likely consequences of active sporozoite traversal through innate cells. Indeed, in vivo vaccination with spect1 knockout sporozoites, which are deficient in cell traversal, induced a defective CD8 T-cell response, showcasing a potential role for cell traversal in the induction of effective adaptive responses. Taken together, these findings open up several interesting avenues for future research which will paint a clearer picture of innate immune responses to Plasmodium parasites

Use of a comprehensive patient safety tool in primary care practices

Purpose To present a tool that can be used to evaluate patient safety in both nurse‐led and physician‐led practices. Data source This article describes our experience with the Physician Practice Patient Safety Assessment (PPPSA) tool in six safety net practices—three of which were primary care nurse‐managed health centers and three were physician‐led federally qualified health centers. The information provided is from the tool itself and how it might be used in clinical settings, especially primary care. Conclusions The PPPSA is a tool to measure the extent to which patient safety practices are rigorously and systematically implemented throughout a health center. The tool's methodology requires discussion and consensus, incorporating a team approach with multiple perspectives within a center. It is designed to promote changes in practices that would improve patient safety. Implications for practice The tool has enormous relevance for primary care settings, especially those preparing themselves for patient‐centered medical home status and meaningful use. But most important, it has relevance as we create healthcare environments that promote patient safety and a practice culture that is truly patient centered.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/99022/1/jaan12021.pd

Acute Morphological and Toxicological Effects in a Human Bronchial Coculture Model after Sulfur Mustard Exposure.

International audienceSulfur mustard (SM) is a strong alkylating agent. Inhalation of SM causes acute lung injury accompanied by severe disruption of the airway barrier. In our study, we tested the acute effects after mustard exposure in an in vitro coculture bronchial model of the proximal barrier. To achieve this, we seeded normal human bronchial epithelial explant-outgrowth cells (HBEC) together with lung fibroblasts as a bilayer on filter plates and exposed the bronchial model after 31 days of differentiation to various concentrations of SM (30, 100, 300, and 500mM). The HBEC formed confluent layers, expressing functional tight junctions as measured by transepithelial electrical resistance (TER). Mucus production and cilia formation reappeared in the coculture model. TER was measured after 2 and 24 h following treatment. Depending on the different concentrations , TER decreased in the first 2 h up to 55% of the control at the highest concentration. After 24 h, TER seemed to recover because at concentrations up to 300mM values were equal to the control. SM induced a widening of intercellular spaces and a loss in cell-matrix adhesion. Mucus production increased with the result that cilia ceased to beat. Changes in the proinflammatory cytokines in-terleukin (IL)-6 and IL-8 were also observed. Apoptotic markers such as cytochrome c, p53, Fas-associated protein with death domain, and procaspase-3 were significantly induced at concentrations of less than 100mM. In summary, SM induces morphological and biochemical changes that reflect pathological effects of SM injury in vivo. It is hoped to use this coculture model to understand further the pathogenesis of SM-induced barrier injury and to search for novel approaches in SM therapy

Barrier functions and paracellular integrity in human cell culture models of the proximal respiratory unit.

International audienceAirway epithelial cells provide a barrier to the translocation of inhaled materials. Tight (TJ) and adherens junctions (AJ) play a key role in maintaining barrier functions, and are responsible for the selective transport of various substances through the paracellular pathway. In this study we compared a bronchial cell line (16HBE14o-) and primary bronchial cells (HBEC), both cocultivated with the fibroblast cell line Wi-38, with respect to their structural differentiation and their reaction to cytokine stimulation. HBEC formed a pseudostratified epithelial layer and expressed TJ and AJ proteins after 2 weeks in coculture. Mucus-producing and ciliated cells were found within 24 days. Additionally, a beating activity of the ciliated HBEC (14-19 Hz) could be detected. 16HBE14o-in coculture showed a multilayered growth without differentiation to a pseudostratified airway epithelium. Simultaneous exposure to TNF-a-and IFN-c-induced significant changes in barrier function and paracellular permeability in the cocultures of HBEC/Wi-38 but not in the 16HBE14o-/Wi-38. In summary, HBEC in coculture mimic the structure of native polarized bronchial epithelium showing basal, mucus-producing and ciliated cells. Our system provides an opportunity to examine the factors that influence barrier and mucociliary function of bronchial epithelium within a time frame of 3 weeks up to 3 months in an in vivo-like differentiated model

Quantitative CT analysis of lung parenchyma to improve malignancy risk estimation in incidental pulmonary nodules.

OBJECTIVES To assess the value of quantitative computed tomography (QCT) of the whole lung and nodule-bearing lobe regarding pulmonary nodule malignancy risk estimation. METHODS A total of 251 subjects (median [IQR] age, 65 (57-73) years; 37% females) with pulmonary nodules on non-enhanced thin-section CT were retrospectively included. Twenty percent of the nodules were malignant, the remainder benign either histologically or at least 1-year follow-up. CT scans were subjected to in-house software, computing parameters such as mean lung density (MLD) or peripheral emphysema index (pEI). QCT variable selection was performed using logistic regression; selected variables were integrated into the Mayo Clinic and the parsimonious Brock Model. RESULTS Whole-lung analysis revealed differences between benign vs. malignant nodule groups in several parameters, e.g. the MLD (-766 vs. -790 HU) or the pEI (40.1 vs. 44.7 %). The proposed QCT model had an area-under-the-curve (AUC) of 0.69 (95%-CI, 0.62-0.76) based on all available data. After integrating MLD and pEI into the Mayo Clinic and Brock Model, the AUC of both clinical models improved (AUC, 0.91 to 0.93 and 0.88 to 0.91, respectively). The lobe-specific analysis revealed that the nodule-bearing lobes had less emphysema than the rest of the lung regarding benign (EI, 0.5 vs. 0.7 %; p < 0.001) and malignant nodules (EI, 1.2 vs. 1.7 %; p = 0.001). CONCLUSIONS Nodules in subjects with higher whole-lung metrics of emphysema and less fibrosis are more likely to be malignant; hereby the nodule-bearing lobes have less emphysema. QCT variables could improve the risk assessment of incidental pulmonary nodules. KEY POINTS • Nodules in subjects with higher whole-lung metrics of emphysema and less fibrosis are more likely to be malignant. • The nodule-bearing lobes have less emphysema compared to the rest of the lung. • QCT variables could improve the risk assessment of incidental pulmonary nodules

SLUDGE COMPOSITION DURING OZONE ACTIVATION: PRELIMINARY RESULTS OF ITS REUSE CAPABILITIES AS CARBON SOURCE FOR DENITRIFICATION

Recirculation Aquaculture Systems (RAS) reduce water consumption but require costly filtering methods needed in order to maintain adequate levels of accumulating compounds, such as nitrogenous compounds and sludge. Sludge (faeces and waste diet) is mechanically removed by drum filters and settling systems and disposed of, while nitrogen compounds are reduced via nitrification-denitrification filters, the latter of which requires of supplementary commercial carbon sources. Sludge is a source of particulate carbon, potentially for use in denitrification, equivalent to ca 20% of feed input (Lekang 2013). The reutilization of sludge implies the correct accumulation and storage to avoid uncontrolled decomposition by partial exposure to aerobic and anaerobic conditions and the disintegration of complex molecules into easily biodegradable nutrients. Ozone exposure is a potential method to promote mineralization and allows formation of biodegradable intermediates. The present study investigated the potential of sludge as an alternative carbon source for denitrification and asks: i) How much time should the sludge be exposed to ozone in order to achieve the highest levels of carbon intermediates in solution? ii) What are the remaining constituents of the solid phase of the sludge post- ozonisation prone be used as nutrients by denitrifying bacteria? iii) Is there an influence of different fish diet composition on the fatty acid content of sludge? iv) Is denitrification possible when using ozone-treated sludge as a carbon source? As particulate matter represents a great amount of the sludge discharge, this study aimed to estimate the dissociative effect of ozonisation on the solid phase and the physicochemical changes that this process could bring to the water matrix in terms of carbon and nitrogen content present in solution and in particulate state. The preliminary results of a batch pilot study using ozone-activated sludge vs. a common commercial carbon source for denitrification are also provided

Prevalence and potential relevance of hyperuricemia in pediatric kidney transplant recipients—a CERTAIN registry analysis

Background: Asymptomatic hyperuricemia is frequently observed in pediatric kidney transplant recipients; symptomatic hyperuricemia, however, is a rare complication. Only few data are available in this patient population. We, therefore, investigated the prevalence of hyperuricemia and its association with kidney transplant function and blood pressure in a multicenter cohort of pediatric kidney transplant recipients. Methods: This is a retrospective, observational multicenter registry study. All pediatric kidney transplant recipients in the CERTAIN database with at least one documented serum uric acid level and a follow-up of 5 years posttransplant were eligible. We identified 151 patients with 395 measurements of serum uric acid. We calculated the prevalence of hyperuricemia, analyzed potential risk factors and clinical consequences such as elevated blood pressure and reduced estimated glomerular filtration rate (eGFR). Statistical analysis was performed using IBM SPSS Statistics 26. Results: One hundred and ten of 395 (27.8%) serum uric acid levels were above 416 µmol/L (7.0 mg/dL), defined as the upper limit of normal. Univariate analysis showed a significant (p = .026) inverse association of serum uric acid with eGFR overtime. There was no significant association of serum uric acid concentrations with body mass index (z-score), blood pressure (z-score), or sex. No episodes of gout were documented. Conclusion: This study shows that hyperuricemia is present in a considerable number of patients sometime after pediatric kidney transplantation and is associated with lower eGFR. Whether hyperuricemia contributes to faster decline of graft function or to the overall cardiovascular risk of these patients remains to be elucidated. Keywords: gout; long-term outcome; pediatric kidney transplantation; uric acid; uric acid-lowering therapy