bluuebunny/crossref_metadata_2025 huggingface dataset:
Pharmacologic Inhibition of ADAM10 Attenuates Brain Tissue Loss, Axonal Injury and Pro-inflammatory Gene Expression Following Traumatic Brain Injury in Mice
Authors: Appel Dominik , Hummel Regina , Weidemeier Martin , Endres Kristina , Gölz Christina , Schäfer Michael K. E.
Published: March 2021

The α-secretase A disintegrin and metalloprotease 10 (ADAM10) regulates various physiological and pathophysiological processes. Despite its broad functional implications during development, plasticity, and disease, no pharmacological approaches to inhibit ADAM10 in acute brain injury have been reported. Here, we examined the effects of the ADAM10 inhibitor GI254023X on the neurological and histopathological outcome after experimental traumatic brain injury (TBI). C57BL/6N mice were subjected to the controlled cortical impact (CCI) model of TBI or sham procedure and received GI254023X or vehicle during the acute phase of injury (n = 40, 100 mg/kg, 25% DMSO, 0.1 M Na2CO3, intraperitoneal, 30 min and 24 h after TBI). GI254023X treatment did not improve neurological deficits from 1 to 7 days post-injury (dpi) but animals treated with GI254023X exhibited smaller brain lesions compared to vehicle treatment. Determination of brain mRNA expression by quantitative PCR showed that TBI-induced up-regulation of Adam10 and Adam17 was not influenced by GI254023X but the up-regulation of the matrix metalloproteinase genes Mmp2 and Mmp9 was attenuated. GI254023X treatment further increased the T cell marker Cd247 but did not affect blood brain barrier integrity, as assessed by Occludin mRNA expression and IgG brain extravasation. However, in agreement with neuroprotective effects of ADAM10 inhibition, GI254023X treatment attenuated axonal injury, as indicated by decreased generation of spectrin breakdown products (SBDPs) and decreased immunostaining using anti-non-phosphorylated neurofilament (SMI-32). Interestingly, reduced axonal injury in GI254023X-treated animals coincided with subtle mRNA dysregulation in the glutamate receptor subunit genes Gria1 and Grin2b. Quantitative PCR also revealed that GI254023X mitigated up-regulation of the pro-inflammatory markers Il6, Tnfa, and Lcn2 but not the up-regulation of the pan-microglia marker Aif1, the M2 microglia marker Arg1 and the reactive astrocyte marker Gfap. Taken together, the ADAM10 inhibitor GI254023X attenuates brain tissue loss, axonal injury and pro-inflammatory gene expression in the CCI model of TBI. These results suggest that ADAM10 may represent a therapeutic target in the acute phase of TBI.
Use of Artificial Intelligence and Machine Learning for Discovery of Drugs for Neglected Tropical Diseases
Authors: Winkler David A.
Published: March 2021

Neglected tropical diseases continue to create high levels of morbidity and mortality in a sizeable fraction of the world’s population, despite ongoing research into new treatments. Some of the most important technological developments that have accelerated drug discovery for diseases of affluent countries have not flowed down to neglected tropical disease drug discovery. Pharmaceutical development business models, cost of developing new drug treatments and subsequent costs to patients, and accessibility of technologies to scientists in most of the affected countries are some of the reasons for this low uptake and slow development relative to that for common diseases in developed countries. Computational methods are starting to make significant inroads into discovery of drugs for neglected tropical diseases due to the increasing availability of large databases that can be used to train ML models, increasing accuracy of these methods, lower entry barrier for researchers, and widespread availability of public domain machine learning codes. Here, the application of artificial intelligence, largely the subset called machine learning, to modelling and prediction of biological activities and discovery of new drugs for neglected tropical diseases is summarized. The pathways for the development of machine learning methods in the short to medium term and the use of other artificial intelligence methods for drug discovery is discussed. The current roadblocks to, and likely impacts of, synergistic new technological developments on the use of ML methods for neglected tropical disease drug discovery in the future are also discussed.
Template-Free Synthesis of One-Dimensional g-C3N4 Chain Nanostructures for Efficient Photocatalytic Hydrogen Evolution
Authors: Zhang Mingyi , Sun Ye , Chang Xin , Zhang Peng
Published: March 2021

The development of graphite-carbon nitride (g-C3N4) photocatalyst is of great significance for various visible utilization applications. Control the nanostructures of g-C3N4 can tailor its photocatalytic performance. In this paper, one-dimensional chain-like g-C3N4 was successfully synthesized by heat-induced polymerization of melamine which was saturated in ethylene glycol. The photocatalytic hydrogen production rate (HER) of the prepared g-C3N4 chain enhanced about 3 times than that of bulk g-C3N4, increasing from 9.6 μmolh−1 to 28.7 μmolh−1. The improved photocatalytic activity of the g-C3N4 chain was attributed to the advantages of porosity and nanostructure. The extraordinary nanopores result in an enlarged specific surface area for adsorption and the production of abundantly available channels for charge transfer. The one-dimensional chain-like structure can facilitate the exposure of internal/external active sites as many as possible, and induce the directional migration of charge carriers.
Deceiving Phenotypic Susceptibility Results on a Klebsiella pneumoniae Blood Isolate Carrying Plasmid-Mediated AmpC Gene blaDHA-1
Authors: Realegeno Susan , Ward Kevin , Garner Omai B. , Yang Shangxin
Published: March 2021

Carbapenem-resistant Klebsiella pneumoniae (CRKP) frequently causes hospital-acquired infections and is associated with high morbidity and mortality. CRKP can have multiple resistance mechanisms and only a few can be routinely detected by commercial molecular or phenotypic assays making surveillance for CRKP particularly challenging. In this report, we identified and characterized an unusual non–carbapenemase-producing CRKP carrying a rare plasmid-borne inducible AmpC gene, blaDHA-1. The isolate was recovered from blood culture of a 67-year-old female presenting with sepsis post bladder surgery and ureteral stent removal. The primary isolate displayed an indeterminate susceptibility pattern for ceftriaxone by broth microdilution, but was susceptible by disk diffusion with one colony growing within the zone of inhibition. The ceftriaxone resistant colony was sub-cultured and had a minimum inhibitory concentration (MIC) of 2 ug/ml for imipenem (intermediate) and a zone size of 18 mm for ertapenem (resistant), but remained susceptible to cefepime and meropenem. Further phenotypic characterization of this sub-cultured isolate showed carbapenemase activity. Whole genome sequencing (WGS) revealed the presence of two subpopulations of a K. pneumoniae (MLST sequence type 11) from the primary blood culture isolate: one pan-susceptible to beta-lactams tested and the other resistant to the 3rd generation cephalosporins and ertapenem. WGS analysis identified the resistant K. pneumoniae harboring IncFIB(K) and IncR plasmids and the presence of plasmid-borne beta-lactam resistance genes blaOXA-1 and blaDHA-1, an inducible AmpC gene. Additional resistance genes against quinolones (aac(6′)-Ib-cr, oqxA, oqB), aminoglycoside (aph(3′)-Ia), sulfonamide (sul1), and tetracycline (tet(A)) were also identified. DHA-1 positive K. pneumoniae have been previously identified outside the US, particularly in Asia and Europe, but limited cases have been reported in the United States and may be underrecognized. Our study highlights the importance of using both extended phenotypic testing and WGS to identify emerging resistance mechanisms in clinical Enterobacterales isolates with unusual antimicrobial resistance patterns.
Routine Oxygen Therapy Does Not Improve Health-Related Quality of Life in Patients With Acute Myocardial Infarction—Insights From the Randomized DETO2X-AMI Trial
Authors: Hofmann Robin , Befekadu Abebe Tamrat , Herlitz Johan , James Stefan K. , Erlinge David , Yndigegn Troels , Alfredsson Joakim , Kellerth Thomas , Ravn-Fischer Annica , Völz Sebastian , Lauermann Jörg , Jernberg Tomas , Lindahl Bertil , Langenskiöld Sophie
Published: March 2021

Background: After decades of ubiquitous oxygen therapy in all patients with acute myocardial infarction (MI), recent guidelines are more restrictive based on lack of efficacy in contemporary trials evaluating hard clinical outcomes in patients without hypoxemia at baseline. However, no evidence regarding treatment effects on health-related quality of life (HRQoL) exists. In this study, we investigated the impact of routine oxygen supplementation on HRQoL 6–8 weeks after hospitalization with acute MI. Secondary objectives included analyses of MI subtypes, further adjustment for infarct size, and oxygen saturation at baseline and 1-year follow-up.

Methods: In the DETermination of the role of Oxygen in suspected Acute Myocardial Infarction (DETO2X-AMI) trial, 6,629 normoxemic patients with suspected MI were randomized to oxygen at 6 L/min for 6–12 h or ambient air. In this prespecified analysis, patients younger than 75 years of age with confirmed MI who had available HRQoL data by European Quality of Life Five Dimensions questionnaire (EQ-5D) in the national registry were included. Primary endpoint was the EQ-5D index assessed by multivariate linear regression at 6–10 weeks after MI occurrence.

Results: A total of 3,086 patients (median age 64, 22% female) were eligible, 1,518 allocated to oxygen and 1,568 to ambient air. We found no statistically significant effect of oxygen therapy on EQ-5D index (−0.01; 95% CI: −0.03–0.01; p = 0.23) or EQ-VAS score (−0.57; 95% CI: −1.88–0.75; p = 0.40) compared to ambient air after 6–10 weeks. Furthermore, no significant difference was observed between the treatment groups in EQ-5D dimensions. Results remained consistent across MI subtypes and at 1-year follow-up, including further adjustment for infarct size or oxygen saturation at baseline.

Conclusions: Routine oxygen therapy provided to normoxemic patients with acute MI did not improve HRQoL up to 1 year after MI occurrence.

Clinical Trial Registration:ClinicalTrials.gov number, NCT01787110.
Ge/Si and Ge Isotope Fractionation During Glacial and Non-glacial Weathering: Field and Experimental Data From West Greenland
Authors: Baronas J. Jotautas , Hammond Douglas E. , Bennett Mia M. , Rouxel Olivier , Pitcher Lincoln H. , Smith Laurence C.
Published: March 2021

Glacial environments offer the opportunity to study the incipient stages of chemical weathering due to the high availability of finely ground sediments, low water temperatures, and typically short rock-water interaction times. In this study we focused on the geochemical behavior of germanium (Ge) in west Greenland, both during subglacial weathering by investigating glacier-fed streams, as well as during a batch reactor experiment by allowing water-sediment interaction for up to 2 years in the laboratory. Sampled in late August 2014, glacial stream Ge and Si concentrations were low, ranging between 12–55 pmol/L and 7–33 µmol/L, respectively (Ge/Si = 0.9–2.2 µmol/mol, similar to parent rock). As reported previously, the dissolved stable Ge isotope ratio (δ74Ge) of the Watson River was 0.86 ± 0.24‰, the lowest among global rivers and streams measured to date. This value was only slightly heavier than the suspended load (0.48 ± 0.23‰), which is likely representative of the bulk parent rock composition. Despite limited Ge/Si and δ74GeGe fractionation, both Ge and Si appear depleted relative to Na during subglacial weathering, which we interpret as the relatively congruent uptake of both phases by amorphous silica (aSi). Continued sediment-water interaction over 470–785 days in the lab produced a large increase in dissolved Si concentrations (up to 130–230 µmol/L), a much smaller increase in dissolved Ge (up to ∼70 pmol/L), resulting in a Ge/Si decrease (to 0.4–0.5 µmol/mol) and a significant increase in δ74Ge (to 1.9–2.2‰). We argue that during the experiment, both Si and Ge are released by the dissolution of previously subglacially formed aSi, and Ge is then incorporated into secondary phases (likely adsorbed to Fe oxyhydroxides), with an associated Δ74Gesecondary−dissolved fractionation factor of −2.15 ± 0.46‰. In summary, we directly demonstrate Ge isotope fractionation during the dissolution-precipitation weathering reactions of natural sediments in the absence of biological Ge and Si uptake, and highlight the significant differences in Ge behavior during subglacial and non-glacial weathering.
A Possible Roll-Over Slab Geometry Under the Caroline Plate Imaged by Monte Carlo Finite-Frequency Traveltime Inversion of Teleseismic SS Phases
Authors: Fuji Nobuaki , Jang Hyoihn , Nakao Atsushi , Kim YoungHee , Fernández-Blanco David , Lee Sang-Mook , Schroeder Alexia , Konishi Kensuke
Published: March 2021

The shape of a subducting slab varies as a function of trench motion. Two end-members of subduction modes are geodynamically possible: roll-back mode underneath neighboring plates and roll-over mode underneath the plate itself. Whereas most of major slabs seem to roll back while the Pacific plate shows a slab piling behavior down to ∼1,000 km depth under the Mariana trench, no clear evidence of slab roll-over in nature has been reported so far. Here we show a possible roll-over slab beneath the Caroline microplate, revealed from its three-dimensional seismic velocity structure derived by analyzing teleseismic reverberating SS phases. We suggest that slab roll-over is driven by at least two factors: 1) the overall buoyancy and fragility of the Caroline microplate at the surface, induced by a thin hot mantle plume that rises from depths ≥800 km; and 2) the pushing force of the Pacific plate acting on the trailing edge of the Caroline plate.
Bayesian Analysis to Determine Relative Significance of Inputs of a Rock-Physics Model
Authors: Spikes Kyle T. , Sen Mrinal K.
Published: March 2021

Rock-physics models relate rock properties to elastic properties through non-unique relationships and often in the presence of seismic data that contain significant noise. A set of inputs define the rock-physics model, and any errors in that model map directly into uncertainty in target seismic-scale amplitudes, velocities, or inverted impedances. An important aspect of using rock-physics models in this manner is to determine and understand the significance of the inputs into a rock-physics model under consideration. Such analysis enables the design of prior distributions that are informative within a reservoir-characterization formulation. We use the framework of Bayesian analysis to find internal dependencies and correlations among the inputs. This process requires the assignments of prior distributions, and calculation of the likelihood function, whose product is the posterior distribution. The data are well-log data that come from a hydrocarbon-bearing set of sands from the Gulf of Mexico. The rock-physics model selected is the soft-sand model, which is applicable to the data from the reservoir sands. Results from the Bayesian algorithm are multivariate histograms that demonstrate the most frequent values of the inputs given the data. Four analyses are applied to different subsets of the reservoir sands, and each reveals some correlations among certain model inputs. This quantitative approach points out the significance of a singular or joint set of rock-physics model parameters.
Disease and Treatment-Related Burden in Patients With Acromegaly Who Are Biochemically Controlled on Injectable Somatostatin Receptor Ligands
Authors: Fleseriu Maria , Molitch Mark , Dreval Alexander , Biermasz Nienke R. , Gordon Murray B. , Crosby Ross D. , Ludlam William H. , Haviv Asi , Gilgun-Sherki Yossi , Mathias Susan D.
Published: March 2021

Medical treatment for acromegaly commonly involves receiving intramuscular or deep subcutaneous injections of somatostatin receptor ligands (SRLs) in most patients. In addition to side effects of treatment, acromegaly patients often still experience disease symptoms even when therapy is successful in controlling GH and IGF-1 levels. Symptoms and side effects can negatively impact patients’ health-related quality of life. In this study, we examine the disease- and treatment-related burden associated with SRL injections as reported through the use of the Acromegaly Treatment Satisfaction Questionnaire (Acro-TSQ©) and clinician-reported symptom severity through the Acromegaly Index of Severity (AIS). Patients included in this analysis were enrolled in a randomized phase 3 study, were biochemically-controlled (an IGF-1 < 1.3 × the upper limit of normal [ULN] and average GH < 2.5 ng/ml) and receiving SRL injections for ≥6 months with a stable dose of either long-acting octreotide or lanreotide monotherapy for ≥4 months. The sample (N = 91) was 65% female, 91% Caucasian, with a mean [standard deviation (SD)] age of 53 (1) years. Two-thirds of patients reported that they still experience acromegaly symptoms; 82% of these said they experience symptoms all of the time. Three-fourths experienced gastrointestinal (GI) side effects after injections, and 77% experienced treatment-related injection site reactions (ISRs). Patients commonly reported that these interfered with their daily life, leisure, and work activities. Those with higher symptom severity, as measured by the AIS, scored significantly worse on several Acro-TSQ domains: Symptom Interference, GI Interference, Treatment Satisfaction, and Emotional Reaction. Despite being biochemically controlled with injectable SRLs, most patients reported experiencing acromegaly symptoms that interfere with daily life, leisure, and work. GI side effects and ISRs were also common. This study highlights the significant disease burden that still persists for patients with acromegaly that have achieved biochemical control with the use of injectable SRLs.
Soil Microbiome Structure and Function in Ecopiles Used to Remediate Petroleum-Contaminated Soil
Authors: Wang M. , Garrido-Sanz D. , Sansegundo-Lobato P. , Redondo-Nieto M. , Conlon R. , Martin M. , Mali R. , Liu X. , Dowling D. N. , Rivilla R. , Germaine K. J.
Published: March 2021

The soil microbiome consists of a vast variety of microorganisms which contribute to essential ecosystem services including nutrient recycling, protecting soil structure, and pathogen suppression. Recalcitrant organic compounds present in soils contaminated with fuel oil can lead to a decrease in functional redundancy within soil microbiomes. Ecopiling is a passive bioremediation technique involving biostimulation of indigenous hydrocarbon degraders, bioaugmentation through inoculation with known petroleum-degrading consortia, and phytoremediation. The current study investigates the assemblage of soil microbial communities and pollutant-degrading potential in soil undergoing the Ecopiling process, through the amplicon marker gene and metagenomics analysis of the contaminated soil. The analysis of key community members including bacteria, fungi, and nematodes revealed a surprisingly diverse microbial community composition within the contaminated soil. The soil bacterial community was found to be dominated by Alphaproteobacteria (60–70%) with the most abundant genera such as Lysobacter, Dietzia, Pseudomonas, and Extensimonas. The fungal community consisted mainly of Ascomycota (50–70% relative abundance). Soil sequencing data allowed the identification of key enzymes involved in the biodegradation of hydrocarbons, providing a novel window into the function of individual bacterial groups in the Ecopile. Although the genus Lysobacter was identified as the most abundant bacterial genus (11–46%) in all of the contaminated soil samples, the metagenomic data were unable to confirm a role for this group in petrochemical degradation. Conversely, genera with relatively low abundance such as Dietzia (0.4–9.0%), Pusillimonas (0.7–2.3%), and Bradyrhizobium (0.8–1.8%) did possess genes involved in aliphatic or aromatic compound degradation.
Capacity Building of Health Professionals on Genetics and Genomics Practice: Evaluation of the Effectiveness of a Distance Learning Training Course for Italian Physicians
Authors: Calabrò Giovanna Elisa , Tognetto Alessia , Mazzaccara Alfonso , Barbina Donatella , Carbone Pietro , Guerrera Debora , Di Pucchio Alessandra , Federici Antonio , Ricciardi Walter , Boccia Stefania
Published: March 2021

Background

The rapid spread of personalized medicine requires professionals to manage the “omics revolution.” Therefore, the genetics/genomics literacy of healthcare professionals should be in line with the continuous advances in this field, in order to implement its potential implications for diagnosis, control and treatment of diseases. The present study investigates the effectiveness of a distance learning course on genetics and genomics targeted at medical doctors.

Methods

In the context of a project funded by the Italian Ministry of Health, we developed a distance learning course, entitled Genetics and Genomics practice. The course focused on genetic/genomics testing, pharmacogenetics and oncogenomics and was developed according to andragogical training methods (Problem-based Learning and Case-based Learning). We used a pre-test vs. post-test study design to assess knowledge improvement on a set of 10 Multiple Choice Questions (MCQs). We analyzed the proportion of correct answers for each question pre and post-test and the mean score difference stratified by gender, age, professional status and medical discipline. Moreover, the test was submitted to the participants 8 months after the conclusion of the course (follow-up), in order to assess the retained knowledge.

Results

The course was completed by 1,637 Italian physicians, most of which were primary care physicians (20.8%), public health professionals (11.5%) and specialist pediatricians (10.6%). The proportion of correct answers increased in the post-test for all the MCQs. The overall mean score significantly increased, from 59.46 in the pre-test to 71.42 in the post-test (p < 0.0001). The comparison in test performance between follow-up and pre-test demonstrated an overall knowledge improvement.

Conclusion

Genomics literacy among healthcare professionals is essential to ensure optimal translation to healthcare delivery of research. The results of this course suggest that distance-learning training in genetic/genomics practice represents an effective method to improve physicians’ knowledge in the immediate and mid-term time scale. A preprint version of this paper is available at: https://www.researchsquare.com/article/rs-10083/v1.
Wnt Inhibition Sensitizes PD-L1 Blockade Therapy by Overcoming Bone Marrow-Derived Myofibroblasts-Mediated Immune Resistance in Tumors
Authors: Huang Tinglei , Li Fuli , Cheng Xiaojiao , Wang Jianzheng , Zhang Wenhui , Zhang Baiwen , Tang Yao , Li Qingli , Zhou Cong , Tu Shuiping
Published: March 2021

Cancer-associated fibroblasts (CAFs) has been recognized as one cause of tumor resistance to immune checkpoint blockade therapy, but the underlying mechanisms still remain elusive. In the present study, a bone marrow-derived CAF (BMF) -rich tumor model is successfully established by subcutaneously mixed inoculation of BMFs and tumor cells into mice and the BMF-mixed tumor xenografts are demonstrated to be resistant to anti-PD-L1 antibody immunotherapy compared to the mere tumor xenografts. In vitro assays via the co-culture system of BMFs and tumor cells indicate that the co-cultured BMFs are induced to overexpress PD-L1, while there is no such a phenomenon in the co-cultured cancer cells. The further knock-out of PD-L1 in BMFs rescues the sensitivity of BMF-mixed tumor xenografts to PD-L1 blockade therapy. Mechanistically, via the microarray assay, we identify that the upregulation of PD-L1 in BMFs stimulated by cancer cells is medicated by the activation of the Wnt/β-catenin signaling pathway in BMFs. Moreover, the administration of Wnt/β-catenin signaling inhibitors, including XAV-939 and Wnt-C59, distinctly inhibits the upregulation of PD-L1 expression in the co-cultured BMFs. The further combination administration of XAV-939 significantly potentiates the therapeutic outcome of PD-L1 blockade therapy in BMF-mixed tumors. In summary, our study demonstrates that Wnt inhibition augments PD-L1 blockade efficacy by overcoming BMF-mediated immunotherapy resistance.
Poor Birth Outcomes in Malaria in Pregnancy: Recent Insights Into Mechanisms and Prevention Approaches
Authors: Chua Caroline L. L. , Hasang Wina , Rogerson Stephen J. , Teo Andrew
Published: March 2021

Pregnant women in malaria-endemic regions are susceptible to malaria in pregnancy, which has adverse consequences on birth outcomes, including having small for gestational age and preterm babies. These babies are likely to have low birthweights, which predisposes to infant mortality and lifelong morbidities. During malaria in pregnancy, Plasmodium falciparum-infected erythrocytes express a unique variant surface antigen, VAR2CSA, that mediates sequestration in the placenta. This process may initiate a range of host responses that contribute to placental inflammation and dysregulated placental development, which affects placental vasculogenesis, angiogenesis and nutrient transport. Collectively, these result in the impairment of placental functions, affecting fetal development. In this review, we provide an overview of malaria in pregnancy and the different pathological pathways leading to malaria in pregnancy-associated low birthweight. We also discuss current prevention and management strategies for malaria in pregnancy, and some potential therapeutic interventions that may improve birth outcomes. Lastly, we outline some priorities for future research that could bring us one step closer to reducing this health burden.
Human Mast Cell Line HMC1 Expresses Functional Mas-Related G-Protein Coupled Receptor 2
Authors: Hermans Maud A. W. , van Stigt Astrid C. , van de Meerendonk Sanne , Schrijver Benjamin , van Daele Paul L. A. , van Hagen Petrus M. , van Splunter Marloes , Dik Willem A.
Published: March 2021

The Mas-related G-protein-coupled receptor X2 (MRGPRX2) is prominently expressed by mast cells and induces degranulation upon binding by different ligands. Its activation has been linked to various mast cell-related diseases, such as chronic spontaneous urticaria, atopic dermatitis and asthma. Therefore, inhibition of MRGPRX2 activity represents a therapeutic target for these conditions. However, the exact pathophysiology of this receptor is still unknown. In vitro research with mast cells is often hampered by the technical limitations of available cell lines. The human mast cell types LAD2 and HuMC (human mast cells cultured from CD34+ progenitor cells) most closely resemble mature human mast cells, yet have a very slow growth rate. A fast proliferating alternative is the human mast cell line HMC1, but they are considered unsuitable for degranulation assays due to their immature phenotype. Moreover, the expression and functionality of MRGPRX2 on HMC1 is controversial. Here, we describe the MRGPRX2 expression and functionality in HMC1 cells, and compare these with LAD2 and HuMC. We also propose a model to render HMC1 suitable for degranulation assays by pre-incubating them with latrunculin-B (Lat-B). Expression of MRGPRX2 by HMC1 was proven by RQ-PCR and flowcytometry, although at lower levels compared with LAD2 and HuMC. Pre-incubation of HMC1 cells with Lat-B significantly increased the overall degranulation capacity, without significantly changing their MRGPRX2 expression, phenotype or morphology. The MRGPRX2 specific compound 48/80 (C48/80) effectively induced degranulation of HMC1 as measured by CD63 membrane expression and β-hexosaminidase release, albeit in lower levels than for LAD2 or HuMC. HMC1, LAD2 and HuMC each had different degranulation kinetics upon stimulation with C48/80. Incubation with the MRGPRX2 specific inhibitor QWF inhibited C48/80-induced degranulation, confirming the functionality of MRGPRX2 on HMC1. In conclusion, HMC1 cells have lower levels of MRGPRX2 expression than LAD2 or HuMC, but are attractive forin vitroresearch because of their high growth rate and stable phenotype. HMC1 can be used to study MRGPRX2-mediated degranulation after pre-incubation with Lat-B, which provides the opportunity to explore MPRGRX2 biology in mast cells in a feasible way.
Neutrophil Extracellular Traps: A Potential Therapeutic Target in MPO-ANCA Associated Vasculitis?
Authors: O'Sullivan Kim M. , Holdsworth Stephen R.
Published: March 2021

Our understanding of immune recognition and response to infection and non-infectious forms of cell damage and death is rapidly increasing. The major focus is on host immunity and microbiological invasion. However, it is also clear that these same pathways are important in the initiation and maintenance of autoimmunity and the damage caused to targeted organs. Understanding the involvement of cell death in autoimmune disease is likely to help define critical pathways in the immunopathogenesis of autoimmune disease and new therapeutic targets. An important immune responder cell population in host defense and autoimmunity is the neutrophil. One autoimmune disease where neutrophils play important roles is MPO-ANCA Microscopic Vasculitis. This a severe disease that results from inflammation to small blood vessels in the kidney, the glomeruli (high blood flow and pressure filters). One of the best studied ways in which neutrophils participate in this disease is by cell death through NETosis resulting in the discharge of proinflammatory enzymes and nuclear fragments. In host defense against infection this process helps neutralize pathogens however in auto immunity NETosis results in injury and death to the surrounding healthy tissues. The major autoimmune target in this disease is myeloperoxidase (MPO) which is found uniquely in the cytoplasm of neutrophils. Although the kidney is the major organ targeted in this disease MPO is not expressed in the kidney. Autoantibodies target surface MPO on activated circulating neutrophils resulting in their lodgment in glomerular capillaries where they NETose releasing extracellularly MPO and nuclear fragments initiating injury and planting the key autoantigen MPO. It is the cell death of neutrophils that changes the kidney from innocent bystander to major autoimmune target. Defining the immunopathogenesis of this autoimmune disease and recognizing critical injurious pathways will allow therapeutic intervention to block these pathways and attenuate autoimmune injury. The insights (regarding mechanisms of injury and potential therapeutic targets) are likely to be highly relevant to many other autoimmune diseases.
Schistosomiasis Morbidity Hotspots: Roles of the Human Host, the Parasite and Their Interface in the Development of Severe Morbidity
Authors: Mawa Patrice A. , Kincaid-Smith Julien , Tukahebwa Edridah M. , Webster Joanne P. , Wilson Shona
Published: March 2021

Schistosomiasis is the second most important human parasitic disease in terms of socioeconomic impact, causing great morbidity and mortality, predominantly across the African continent. For intestinal schistosomiasis, severe morbidity manifests as periportal fibrosis (PPF) in which large tracts of macro-fibrosis of the liver, visible by ultrasound, can occlude the main portal vein leading to portal hypertension (PHT), sequelae such as ascites and collateral vasculature, and ultimately fatalities. For urogenital schistosomiasis, severe morbidity manifests as pathology throughout the urinary system and genitals, and is a definitive cause of squamous cell bladder carcinoma. Preventative chemotherapy (PC) programmes, delivered through mass drug administration (MDA) of praziquantel (PZQ), have been at the forefront of schistosomiasis control programmes in sub-Saharan Africa since their commencement in Uganda in 2003. However, despite many successes, ‘biological hotspots’ (as distinct from ‘operational hotspots’) of both persistent high transmission and morbidity remain. In some areas, this failure to gain control of schistosomiasis has devastating consequences, with not only persistently high infection intensities, but both “subtle” and severe morbidity remaining prevalent. These hotspots highlight the requirement to revisit research into severe morbidity and its mechanisms, a topic that has been out of favor during times of PC implementation. Indeed, the focality and spatially-structured epidemiology of schistosomiasis, its transmission persistence and the morbidity induced, has long suggested that gene-environmental-interactions playing out at the host-parasite interface are crucial. Here we review evidence of potential unique parasite factors, host factors, and their gene-environmental interactions in terms of explaining differential morbidity profiles in the human host. We then take the situation of schistosomiasis mansoni within the Albertine region of Uganda as a case study in terms of elucidating the factors behind the severe morbidity observed and the avenues and directions for future research currently underway within a new research and clinical trial programme (FibroScHot).
Elevated Numbers of HIV-Specific Poly-Functional CD8+ T Cells With Stem Cell-Like and Follicular Homing Phenotypes in HIV-Exposed Seronegative Individuals
Authors: Munusamy Ponnan Sivasankaran , Thiruvengadam Kannan , Kathirvel Sujitha , Shankar Janani , Rajaraman Akshaya , Mathaiyan Manikannan , Dinesha Thongadi Ramesh , Poongulali Selvamuthu , Saravanan Shanmugam , Murugavel Kailapuri Gangatharan , Swaminathan Soumya , Tripathy Srikanth Prasad , Neogi Ujjwal , Velu Vijayakumar , Hanna Luke Elizabeth
Published: March 2021

HIV-specific CD8+T cells are known to play a key role in viral control during acute and chronic HIV infection. Although many studies have demonstrated the importance of HIV-specific CD8+T cells in viral control, its correlation with protection against HIV infection remains incompletely understood. To better understand the nature of the immune response that contributes to the early control of HIV infection, we analyzed the phenotype, distribution and function of anti-viral CD8+T cells in a cohort of HIV-exposed seronegative (HESN) women, and compared them with healthy controls and HIV-infected individuals. Further, we evaluated thein vitroviral inhibition activity of CD8+T cells against diverse HIV-1 strains. We found that the HESN group had significantly higher levels of CD8+T cells that express T-stem cell-like (TSCM) and follicular homing (CXCR5+) phenotype with more effector like characteristics as compared to healthy controls. Further, we observed that the HESN population had a higher frequency of HIV-specific poly-functional CD8+T cells with robustin vitrovirus inhibiting capacity against different clades of HIV. Overall, our results demonstrate that the HESN population has elevated levels of HIV-specific poly-functional CD8+T cells with robust virus inhibiting ability and express elevated levels of markers pertaining to TSCM and follicular homing phenotype. These results demonstrate that future vaccine and therapeutic strategies should focus on eliciting these critical CD8+T cell subsets.
Profiling Tissue and Biofluid miR-155-5p, miR-155*, and miR-146a-5p Expression in Graft vs. Host Disease
Authors: Crossland Rachel E. , Norden Jean , Ghimire Sakhila , Juric Mateja Kralj , Pearce Kim F. , Lendrem Clare , Collin Matthew , Mischak-Weissinger Eva , Holler Ernst , Greinix Hildegard T. , Dickinson Anne M.
Published: March 2021

Introduction: Acute graft vs. host disease (aGvHD) is a frequent complication following allogeneic haematopoeitic transplantation (HSCT). Despite recent advances, there are no universally accepted biomarkers to determine development of aGvHD. MicroRNAs miR-146a and miR-155 have been previously associated with aGvHD and show promise as clinically translatable biomarkers. In this study, we performed comprehensive expression profiling of miR-146a, miR-155, and miR-155* expression in aGvHD target tissue and biofluids and relate expression to post-HSCT outcomes.

Materials and Methods: MicroRNA expression was assessed by qRT-PCR in gastrointestinal (n = 31) and skin (n = 31) biopsies as well as serum (exploratory cohort n = 34, verification cohort n = 81, diagnostic cohort n = 65) and urine (exploratory cohort n = 30, verification cohort n = 56, diagnostic cohort n = 20) biofluids, including extracellular vesicle (EV) cohorts (serum EV n = 15, urine EV n = 30). Expression was related to aGvHD incidence, severity and overall survival.

Results: In GI samples, expression of miR-155 (p = 0.03) and miR-146a (p = 0.03) was higher at aGvHD onset compared to patients with no GvHD. In skin biopsies, expression of miR-155 (p = 0.004) was upregulated in aGvHD patients compared to normal control skin. Expression of miR-146a was higher in aGvHD compared to no aGvHD biopsies (p = 0.002). In serum, miR-155 (p = 0.03) and miR-146a (p = 0.02) expression was higher at day 14 (D14), while in urine expression was elevated at D7 post-HSCT in patients who developed aGvHD compared to those disease-free. This was verified in an independent serum (miR-155 p = 0.005, miR-146a p = 0.003) and urine (miR-155 p = 0.02, miR-146a p = 0.04) cohort, where both microRNAs were also associated with aGvHD by ROC analysis. In serum and urine samples taken at the time of aGvHD symptoms, expression of miR-155 and miR-146a was also elevated (serum miR-155 p = 0.03, miR-146a p < 0.001; urine miR-155 p = 0.02, miR-146a p = 0.02). In contrast, miR-146a and miR-155 were downregulated at D14 in serum EVs and at D7 in urine EVs in patients who developed aGvHD compared to those that remained disease-free, in both an exploratory (serum miR-155 p = 0.02, miR-146a p = 0.06; urine miR-155 p = 0.02, miR-146a p = 0.07) and an independent cohort (serum miR-155 p = 0.01, miR-146a p = 0.02).

Conclusions: These results further support a role for miR-155 and miR-146a as non-invasive, clinically relevant biomarkers for aGvHD. However, the link between their involvement in generalized inflammation and in specific pathophysiology requires further investigation at a systemic level.
Effector T Helper Cells Are Selectively Controlled During Pregnancy and Related to a Postpartum Relapse in Multiple Sclerosis
Authors: Koetzier Steven C. , Neuteboom Rinze F. , Wierenga-Wolf Annet F. , Melief Marie-José , de Mol C. Louk , van Rijswijk Angelique , Dik Willem A. , Broux Bieke , van der Wal Ronald , van den Berg Sjoerd A. A. , Smolders Joost , van Luijn Marvin M.
Published: March 2021

Background: Multiple sclerosis (MS) patients are protected from relapses during pregnancy and have an increased relapse risk after delivery. It is unknown how pregnancy controls disease-contributing CD4+ T helper (Th) cells and whether this differs in MS patients who experience a postpartum relapse. Here, we studied the effector phenotype of Th cells in relation to pregnancy and postpartum relapse occurrence in MS.

Methods: Memory skewing and activation of effector Th subsets were analyzed in paired third trimester and postpartum blood of 19 MS patients with and without a postpartum relapse and 12 healthy controls. Ex vivo results were associated with circulating levels of pregnancy-induced hormones and mirrored in vitro by exposing proliferating Th cells to corresponding serum samples.

Results: Based on HSNE-guided analyses, we found that effector memory proportions of Th cells were increased in postpartum vs. third trimester samples from MS patients without a postpartum relapse. This was not seen for relapsing patients or healthy controls. CXCR3 was upregulated on postpartum memory Th cells, except for relapsing patients. These changes were verified by adding sera from the same individuals to proliferating Th cells, but did not associate with third trimester cortisol, estradiol or progesterone levels. For relapsing patients, activated memory Th cells of both third trimester and postpartum samples produced higher levels of pro-inflammatory cytokines.

Conclusion: Effector Th cells are differentially regulated during pregnancy in MS patients, likely via serum-related factors beyond the studied hormones. The pro-inflammatory state of memory Th cells during pregnancy may predict a postpartum relapse.
Development of an Inflammatory CD14+ Dendritic Cell Subset in Humanized Mice
Authors: Iwabuchi Ryutaro , Ide Keigo , Terahara Kazutaka , Wagatsuma Ryota , Iwaki Rieko , Matsunaga Hiroko , Tsunetsugu-Yokota Yasuko , Takeyama Haruko , Takahashi Yoshimasa
Published: March 2021

Humanized mouse models are attractive experimental models for analyzing the development and functions of human dendritic cells (DCs) in vivo. Although various types of DC subsets, including DC type 3 (DC3s), have been identified in humans, it remains unclear whether humanized mice can reproduce heterogeneous DC subsets. CD14, classically known as a monocyte/macrophage marker, is reported as an indicator of DC3s. We previously observed that some CD14+ myeloid cells expressed CD1c, a pan marker for bona fide conventional DC2 (cDC2s), in humanized mouse models in which human FLT3L and GM-CSF genes were transiently expressed using in vivo transfection (IVT). Here, we aimed to elucidate the identity of CD14+CD1c+ DC-like cells in humanized mouse models. We found that CD14+CD1c+ cells were phenotypically different from cDC2s; CD14+CD1c+ cells expressed CD163 but not CD5, whereas cDC2s expressed CD5 but not CD163. Furthermore, CD14+CD1c+ cells primed and polarized naïve CD4+ T cells toward IFN-γ+ Th1 cells more profoundly than cDC2s. Transcriptional analysis revealed that CD14+CD1c+ cells expressed several DC3-specific transcripts, such as CD163, S100A8, and S100A9, and were clearly segregated from cDC2s and monocytes. When lipopolysaccharide was administered to the humanized mice, the frequency of CD14+CD1c+ cells producing IL-6 and TNF-α was elevated, indicating a pro-inflammatory signature. Thus, humanized mice are able to sustain development of functional CD14+CD1c+ DCs, which are equivalent to DC3 subset observed in humans, and they could be useful for analyzing the development and function of DC3s in vivo.
Interplay Between Nanoplastics and the Immune System of the Mediterranean Sea Urchin Paracentrotus lividus
Authors: Murano Carola , Bergami Elisa , Liberatori Giulia , Palumbo Anna , Corsi Ilaria
Published: March 2021

The present study highlights for the first time the interplay between model nanoplastics, such as the carboxyl-modified polystyrene nanoparticles (PS-COOH, 60 nm) NPs and the coelomocytes of the sea urchin Paracentrotus lividus, a benthic grazer widely distributed in Mediterranean coastal area, upon acute in vitro exposure (4 h) (5 and 25 μg mL–1). Insight into PS-COOH trafficking (uptake and clearance) and effects on immune cell functions (i.e., cell viability, lysosomal membrane stability, and phagocytosis) are provided. Dynamic Light Scattering analysis reveals that PS NP suspensions in CF undergo a quick agglomeration, more pronounced for PS-COOH (608.3 ± 43 nm) compared to PS-NH2 (329.2 ± 5 nm). However, both PS NPs are still found as nano-scale agglomerates in CF after 4 h of exposure, as shown by the polydispersity index > 0.3 associated with the presence of different PS NP size populations in the CF. The observed changes in ζ-potential upon suspension in CF (–11.1 ± 3 mV and –12.1 ± 4 mV for PS-COOH and PS-NH2, respectively) confirm the formation of a bio-corona on both PS NPs. Optical fluorescence microscopy and fluorimetric analyses using fluorescently labeled PS-COOH (60 nm) reveal a fast uptake of PS-COOH primarily by phagocytes within 1 h of exposure. Upon transfer to PS NP-free CF, a significant decrease in fluorescence signal is observed, suggesting a fast cell clearance. No effect on cell viability is observed after 4 h of exposure to PS-COOH, however a significant decrease in lysosomal membrane stability (23.7 ± 4.8%) and phagocytic capacity (63.43 ± 3.4%) is observed at the highest concentration tested. Similarly, a significant reduction in cell viability, lysosomal membrane stability and phagocytosis is found upon exposure to PS-NH2 (25 μg mL–1), which confirms the important role of surface charges in triggering immunotoxicity. Overall, our results show that, although being quickly internalized, PS-COOH can be easily eliminated by the coelomocytes but may still be able to trigger an immune response upon long-term exposure scenarios. Taking into account that sediments along Mediterranean coasts are a sink for micro- and nanoplastics, the latter can reach concentrations able to exceed toxicity-thresholds for marine benthic species.
Case Report: Post-operative Angioedema After a Laryngeal Mask Airway Application
Authors: Soghomonyan Suren , Fleming Qian , Bhandary Sujatha P.
Published: March 2021

Angioedema with macroglossia is a rare complication of anesthesia. We present a clinical case of post-operative development of angioedema presenting as macroglossia in a patient receiving chronic therapy with lisinopril, who developed symptoms in the early post-operative period following surgery in a lateral position, when a laryngeal mask airway was used. Possible mechanisms of angioedema and macroglossia development in our patient are discussed along with potential underlying predisposing mechanisms and available therapeutic approaches.
How Do Neurons Signal Itch?
Authors: Schmelz Martin
Published: March 2021

Mechanistic theories of itch are based on neuronal specificity, stimulus intensity, and temporal or spatial discharge patterns. Traditionally, these theories are conceptualized as mutually exclusive, assuming that finding evidence for one theory would exclude the others and could sufficiently explain itch. Current experimental data primarily support the specificity or pattern theory of itch. However, in contrast to an assumed inherent exclusivity, recent results have shown that even within itch-specific pathways in the spinal cord, temporal discharge patterns are important as sustained pruriceptor is required to allow successful transsynaptic signal progression. Also, optogenetic activation of pruriceptors suggest that the combination of neuronal specificity and temporal pattern determines the sensory effect: tonic activation of pruriceptors is required to induce scratching behavior whereas short-lasting stimulation rather causes withdrawal. In addition to the mere duration of discharge, also the temporal pattern or spatial aspects could critically contribute to elicit pruritus instead of pain. Basic neurophysiological studies trying to validate neuronal theories for pruritus in their pure form provide unitary concepts leading from neuronal discharge to the itch sensation. However, the crucial clinical questions have the opposite perspective: which mechanisms explain the chronic itch in a given patient or a given disease? In trying to solve these clinical problems we should not feel bound to the mutual exclusive nature of itch theories, but rather appreciate blending several theories and also accept combinations of itch and pain. Thus, blended versions of itch theories might better suffice for an explanation of chronic itch in patients and will improve the basis for mechanistic treatment options.