39 research outputs found
Metastatic Melanomas Express Inhibitory Low Affinity Fc Gamma Receptor and Escape Humoral Immunity
Our research, inspired by the pioneering works of Isaac Witz in the 1980s, established that 40% of human metastatic melanomas express ectopically inhibitory Fc gamma receptors (FcγRIIB), while they are detected on less than 5% of primary cutaneous melanoma and not on melanocytes. We demonstrated that these tumoral FcγRIIB act as decoy receptors that bind the Fc portion of antimelanoma IgG, which may prevent Fc recognition by the effector cells of the immune system and allow the metastatic melanoma to escape the humoral/natural immune response. The FcγRIIB is able to inhibit the ADCC (antibody dependent cell cytotoxicity) in vitro. Interestingly, the percentage of melanoma expressing the FcγRIIB is high (70%) in organs like the liver, which is rich in patrolling NK (natural killer) cells that exercise their antitumoral activity by ADCC. We found that this tumoral FcγRIIB is fully functional and that its inhibitory potential can be triggered depending on the specificity of the anti-tumor antibody with which it interacts.
Together these observations elucidate how metastatic melanomas interact with and potentially evade humoral immunity and provide direction for the improvement of anti-melanoma monoclonal antibody therapy
Actinomadura meyerae osteitis following wound contamination with hay in a woman in France: a case report
<p>Abstract</p> <p>Introduction</p> <p>Mycetoma is a chronic granulomatous infection caused by environmental fungi or bacteria. It affects dermal and subcutaneous tissues, with putative contiguous extension to muscles or bones. While common in tropical and subtropical areas, mycetoma is rare in Europe.</p> <p>Case presentation</p> <p>We describe a case of <it>Actinomadura meyerae </it>osteitis in a 49-year-old Caucasian woman who suffered a tibia open fracture contaminated with hay; to the best of our knowledge the first case of autochthonous <it>A. meyerae </it>infection reported in France. The bacterium was cultivated from a bone biopsy. Following surgical osteosynthesis and six months of treatment with cotrimoxazole, our patient made a full recovery.</p> <p>Conclusion</p> <p>Our case report suggests that <it>A. meyerae </it>is a potential agent of wound infection in farm workers in contact with hay.</p
Meta-analysis of the clinical performance of commercial SARS-CoV-2 nucleic acid and antibody tests up to 22 August 2020
Background: Reliable testing for SARS-CoV-2 is key for the management of the COVID-19 pandemic. Aim: We estimate diagnostic accuracy for nucleic acid and antibody tests 5 months into the COVID-19 pandemic, and compare with manufacturer-reported accuracy. Methods: We reviewed the clinical performance of SARS-CoV-2 nucleic acid and antibody tests based on 93,757 test results from 151 published studies and 20,205 new test results from 12 countries in the European Union and European Economic Area (EU/ EEA). Results: Pooling the results and considering only results with 95% confidence interval width ≤ 5%, we found four nucleic acid tests, including one pointof- care test and three antibody tests, with a clinical sensitivity ≥ 95% for at least one target population (hospitalised, mild or asymptomatic, or unknown). Nine nucleic acid tests and 25 antibody tests, 12 of them point-of-care tests, had a clinical specificity of ≥ 98%. Three antibody tests achieved both thresholds. Evidence for nucleic acid point-of-care tests remains scarce at present, and sensitivity varied substantially. Study heterogeneity was low for eight of 14 sensitivity and 68 of 84 specificity results with confidence interval width ≤ 5%, and lower for nucleic acid tests than antibody tests. Manufacturer-reported clinical performance was significantly higher than independently assessed in 11 of 32 and four of 34 cases, respectively, for sensitivity and specificity, indicating a need for improvement in this area. Conclusion: Continuous monitoring of clinical performance within more clearly defined target populations is needed.</p
The European Reference Genome Atlas: piloting a decentralised approach to equitable biodiversity genomics
A genomic database of all Earth’s eukaryotic species could contribute to many scientific discoveries; however, only a tiny fraction of species have genomic information available. In 2018, scientists across the world united under the Earth BioGenome Project (EBP), aiming to produce a database of high-quality reference genomes containing all ~1.5 million recognized eukaryotic species. As the European node of the EBP, the European Reference Genome Atlas (ERGA) sought to implement a new decentralised, equitable and inclusive model for producing reference genomes. For this, ERGA launched a Pilot Project establishing the first distributed reference genome production infrastructure and testing it on 98 eukaryotic species from 33 European countries. Here we outline the infrastructure and explore its effectiveness for scaling high-quality reference genome production, whilst considering equity and inclusion. The outcomes and lessons learned provide a solid foundation for ERGA while offering key learnings to other transnational, national genomic resource projects and the EBP.info:eu-repo/semantics/publishedVersio
The European Reference Genome Atlas: piloting a decentralised approach to equitable biodiversity genomics.
ABSTRACT: A global genome database of all of Earth’s species diversity could be a treasure trove of scientific discoveries. However, regardless of the major advances in genome sequencing technologies, only a tiny fraction of species have genomic information available. To contribute to a more complete planetary genomic database, scientists and institutions across the world have united under the Earth BioGenome Project (EBP), which plans to sequence and assemble high-quality reference genomes for all ∼1.5 million recognized eukaryotic species through a stepwise phased approach. As the initiative transitions into Phase II, where 150,000 species are to be sequenced in just four years, worldwide participation in the project will be fundamental to success. As the European node of the EBP, the European Reference Genome Atlas (ERGA) seeks to implement a new decentralised, accessible, equitable and inclusive model for producing high-quality reference genomes, which will inform EBP as it scales. To embark on this mission, ERGA launched a Pilot Project to establish a network across Europe to develop and test the first infrastructure of its kind for the coordinated and distributed reference genome production on 98 European eukaryotic species from sample providers across 33 European countries. Here we outline the process and challenges faced during the development of a pilot infrastructure for the production of reference genome resources, and explore the effectiveness of this approach in terms of high-quality reference genome production, considering also equity and inclusion. The outcomes and lessons learned during this pilot provide a solid foundation for ERGA while offering key learnings to other transnational and national genomic resource projects.info:eu-repo/semantics/publishedVersio
Activated phosphoinositide 3-kinase δ syndrome: Update from the ESID Registry and comparison with other autoimmune-lymphoproliferative inborn errors of immunity
Background: Activated phosphoinositide-3-kinase d syndrome (APDS) is an inborn error of immunity (IEI) with infection susceptibility and immune dysregulation, clinically overlapping with other conditions. Management depends on disease evolution, but predictors of severe disease are lacking. Objectives: This study sought to report the extended spectrum of disease manifestations in APDS1 versus APDS2; compare these to CTLA4 deficiency, NFKB1 deficiency, and STAT3 gain of-function (GOF) disease; and identify predictors of severity in APDS. Methods: Data was collected from the ESID (European Society for Immunodeficiencies)-APDS registry and was compared with published cohorts of the other IEIs. Results: The analysis of 170 patients with APDS outlines high penetrance and early onset of APDS compared to the other IEIs. The large clinical heterogeneity even in individuals with the same PIK3CD variant E1021K illustrates how poorly the genotype predicts the disease phenotype and course. The high clinical overlap between APDS and the other investigated IEIs suggests relevant pathophysiological convergence of the affected pathways. Preferentially affected organ systems indicate specific pathophysiology: bronchiectasis is typical of APDS1; interstitial lung disease and enteropathy are more common in STAT3 GOF and CTLA4 deficiency. Endocrinopathies are most frequent in STAT3 GOF, but growth impairment is also common, particularly in APDS2. Early clinical presentation is a risk factor for severe disease in APDS. Conclusions: APDS illustrates how a single genetic variant can result in a diverse autoimmune-lymphoproliferative phenotype. Overlap with other IEIs is substantial. Some specific features distinguish APDS1 from APDS2. Early onset is a risk factor for severe disease course calling for specific treatment studies in younger patients. (J Allergy Clin Immunol 2023;152:984-96.
Characterization of the ciliary beating efficiency in primary diffuse chronic rhinosinusitis
International audienceCiliary dysfunction may result in chronic airway inflammation and infection causing injury and structural changes to the airway epithelium, leading to a variety of diseases, like bronchiectasis and primary diffuse chronic rhinosinusitis (CRS). Currently, ciliary beating analysis has mainly been studied through the measure of the ciliary beating frequency (CBF) by high-speed digital video microscopy (HSDV). However, a normal CBF has been described in different forms of primary and acquired ciliary dyskinesia
Life history traits and functional immune parameters in the wild trout of the Kerguelen Islands
International audienceCommon trouts (Salmo trutta L.) over 3 years old, were sampled in hydrosystems of Kerguelen Islands in 2010. Biometric and biogeographical data of caught fish were collected in the field. Ages and migratory status of individuals were determined by scale reading and validated by otolithometry and otolith microchemistry (LA-ICPMS). Prey types ingested by trout were determined by analysis of stomach contents. Molecules organochlorine pesticides (OCPs) and PCBs accumulated in the liver and muscle tissues of fish were analyzed by GC-ECD. The immunomarkers were measured directly in the field by appropriate protocols in flow cytometry. Five groups of trouts associated with distinct ecological niches, were defined by the nature of ingested preys. Groups 1 and 3 fed from only benthic invertebrates, group 2 from terrestrial origin preys (insects or arthropods drained by runoff waters), group 4 from pelagic invertebrates (insect larvae) and the group 5 fed exclusively from marine organisms. High significant variations in oxidative burst of blood and pronephros leukocytes were observed between groups. It was particularly true for trouts whose diet consisted in benthic or terrestrial preys which had the highest levels in leukocyte oxidative burst. In addition, a negative influence of hepatic contamination by DDT, HCB and PCB was observed on oxidative burst of pronephrotic leukocytes. The basal level of apoptosis in pronephrotic leukocytes was strongly correlated with muscle bioaccumulation of OCPs, PCBs and PBDEs. Levels of induced apoptosis were particularly high in the blood or in the pronephros of trouts predating preferentially pelagic organisms. This factor was positively correlated with the levels of hepatic OCP, such as DDT. Chronic contamination of trout was also associated with low blood phagocytic activity in migratory trout feeding exclusively marine organisms. In the natural environment, the ecological niche occupied by the fish influence their chemical contamination and plays a major role in the expression levels of immune cell functionality
Synthesis and evaluation of new arylbenzo[b]thiophene and diarylthiophene derivatives as inhibitors of the NorA multidrug transporter of Staphylococcus aureus.
International audienc