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International audience; Coronavirus disease 2019 (COVID-19) caused by the SARS-CoV-2 is particularly severe in older individuals because of an impaired immune response.1 The vaccines presently available are less efficacious in older individuals, because of the senescence of their immune systems.2 A recent letter in Journal of Infection showed the need of a third vaccine dose due to a waning antibody response against new SARS-CoV-2 variants in healthy and immunocompromised individuals.3 In this study, we analysed the protection against Omicron provided by the immune responses of nursing home residents (NHRs) and a population of healthcare workers (HCWs).

International audience; BackgroundIt is currently unknown whether early B cell reconstitution (EBR) in MS patients under rituximab is associated with a risk of relapse or progression.ObjectivesAnalyzing EBR in rituximab-treated patients and its putative association with clinical findings.MethodsProspective lymphocytes immunophenotyping was performed in a monocentric cohort of MS patients treated by rituximab for 2 years. EBR was defined when B cells concentration was > 5 cells/mm3. B cell subsets were retrospectively associated with clinical data. Clinical and radiological monitoring included relapses, EDSS (Expanded Disability Status Scale), SDMT (Symbol Digit Modalities Test), and MRI.Results182 patients were analyzed (61 remitting-relapsing and 121 progressive-active). 38.5% experienced EBR at least once, but very few (7/182) showed systematic reconstitution. Most patients remained stable upon treatment, regardless of the occurrence of EBR. Dynamics of B cell reconstitution featured increased naïve/transitional B cells, and decreased memory subsets. Homeostasis of the B cell compartment differed at baseline between patients experiencing or not EBR upon treatment. In patients with EBR, reciprocal dynamics of transitional and pro-inflammatory double-negative B cell subsets was associated with better response to rituximab treatment.ConclusionEBR is common in rituximab-treated MS patients and is not associated with clinical disease activity. EBR in the peripheral blood may reflect regulatory immunological phenomena in subgroup of patients.

Motivation High-content imaging screens provide a cost-effective and scalable way to assess cell states across diverse experimental conditions. The analysis of the acquired microscopy images involves assembling and curating raw cellular measurements into morphological profiles suitable for testing biological hypotheses. Despite being a critical step, general-purpose and adaptable tools for morphological profiling are lacking and no solution is available for the high-performance Julia programming language. Results Here, we introduce BioProfiling.jl, an efficient end-to-end solution for compiling and filtering informative morphological profiles in Julia. The package contains all the necessary data structures to curate morphological measurements and helper functions to transform, normalize and visualize profiles. Robust statistical distances and permutation tests enable quantification of the significance of the observed changes despite the high fraction of outliers inherent to high-content screens. This package also simplifies visual artifact diagnostics, thus streamlining a bottleneck of morphological analyses. We showcase the features of the package by analyzing a chemical imaging screen, in which the morphological profiles prove to be informative about the compounds' mechanisms of action and can be conveniently integrated with the network localization of molecular targets. Availability and implementation The Julia package is available on GitHub: https://github.com/menchelab/BioProfiling.jl. We also provide Jupyter notebooks reproducing our analyses: https://github.com/menchelab/BioProfilingNotebooks. The data underlying this article are available from FigShare, at https://doi.org/10.6084/m9.figshare.14784678.v2. Supplementary information Supplementary data are available at Bioinformatics online.

International audience; We identified an additional case of documented Rotavirus meningitis in an adult with full medical history. A previously healthy 37-year-old patient presented herself for transient aphasia associated with fever and headaches at the end of a one-week history of gastroenteritis. Cerebrospinal fluid (CSF) analysis revealed lymphocytic meningitis, and treatment with aciclovir was initiated. Rotavirus A reverse transcription-polymerase chain reaction (RT-PCR) was positive in CSF and the patient's stools in favor of Rotavirus meningitis. Testing for other viruses was negative. Magnetic resonance imaging (MRI) showed no signs of encephalitis. Aphasia was resolutive in less than 12 hours, and no neurological symptoms relapsed. All symptoms evolved favorably despite aciclovir discontinuation.Viral sequencing methods have recently identified unexpected viruses as potential causative agents in meningitis, including Rotavirus. We confirm the detectability of Rotavirus in the analysis of CSF in the context of Rotavirus gastroenteritis in an adult. This case suggests postviral headache and neurological deficits with cerebrospinal fluid lymphocytosis (HaNDL) syndrome may be linked to previously undetected direct viral infection of the central nervous system.Therefore, clinicians should consider Rotavirus meningitis in diagnosing meningitis associated with gastroenteritis in adults.

International audience; T follicular helper (Tfh) cells cognately guide differentiation of antigen-primed B cells in secondary lymphoid tissues. 'Tfh-like' populations not expressing the canonical Tfh cell transcription factor BCL6 have also been described, which can aid particular aspects of B cell differentiation. Tfh and Tfh-like cells are essential for protective and pathological humoral immunity. These CD4+ T cells that help B cells are polarized to produce diverse combinations of cytokines and chemokine receptors and can be grouped into distinct subsets that promote antibodies of different isotype, affinity, and duration, according to the nature of immune challenge. However, unified nomenclature to describe the distinct functional Tfh and Tfh-like cells does not exist. While explicitly acknowledging cellular plasticity, we propose categorizing these cell states into three groups based on phenotype and function, paired with their anatomical site of action.

International audience; Le psoriasis est une maladie inflammatoire chronique de la peau, à forte charge émotionnelle, et qui affecte 2 à 3 % de la population mondiale. Elle est fréquemment associée à des comorbidités, comme l’arthrite ou les maladies cardio-métaboliques. Les lésions cutanées se présentent sous la forme de plaques érythémato-squameuses. Elles sont caractérisées par une hyper-prolifération des kératinocytes, une desquamation accélérée et désordonnée et une infiltration de cellules inflammatoires [1]. Le psoriasis résulte du dialogue anormal entre les cellules de l’immunité innée et celles de l’immunité adaptative, dans lequel les lymphocytes Th17 jouent un rôle important. L’expression du facteur de transcription RORgt définit le lignage de ces lymphocytes, qui produisent des interleukines (IL) inflammatoires, dont l’IL-17. Il a été proposé que la mort cellulaire et la libération de l’ADN et de produits anti-microbiens, tels que la cathélicidine LL37, dans la peau lésée de patients psoriasiques activent localement les cellules dendritiques plasmacytoïdes ou les kératinocytes, entraînant la production d’interféron (IFN) de type I et la maturation des cellules dendritiques. Les cellules dendritiques activées migrent vers les ganglions lymphatiques drainant le territoire cutané correspondant, où elles induisent, via la sécrétion d’IL-12 et surtout d’IL-23, la différenciation de lymphocytes T CD4+ auto-réactifs en lymphocytes Th17 producteurs d’IL-17, d’IL-22, d’interféron gamma (IFN-g) et de facteur de nécrose tumorale α (TNF-α) [1]. Les lymphocytes Th17 sont alors recrutés dans la peau, et produisent les cytokines inflammatoires qui induisent la prolifération des kératinocytes, favorisant une boucle de rétroaction positive entre les cellules épithéliales et immunitaires, ce qui entretient l’inflammation [1]. Cibler chacune de ces cytokines (TNF-α, IL-23, IL-17), qui sont des acteurs clés de la pathogenèse du psoriasis [2], avec des anticorps neutralisants a un effet protecteur contre le psoriasis [3-5]. Cependant, ces traitements présentent des inconvénients en termes de coût, de voie d’administration et d’effets indésirables potentiels. D’où l’intérêt de développer de nouvelles thérapies visant à réduire la production de l’ensemble de ces cytokines dans le psoriasis.

International audience; Genetics, environmental factors, and epigenetics all contribute to autoimmune disease onset and progression (Gulati and Brunner, 2018). Most of the earlier research on autoimmune diseases focused on genetics and environmental factors. Research into genetics, in attempting to identify specific risk alleles has had limited success, for example, identifying HLA-DRB1, a complex of genes coding for cell surface proteins, has emerged as a risk allele for autoimmune diseases such as systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) (Niu et al., 2015). However, genetic findings have not been sufficient to explain the majority of RA and SLE cases, autoimmune diseases in general, or the typical delay in initial onset, occurring later in life (early to mid-adulthood), in most autoimmune diseases. Even with identification of a risk allele, it is not clear if it is a cause of the disease or just a subsidiary factor. Likewise, environmental factors (e.g., viruses, toxins, bacteria, etc.) also present confusion as to their role since a variety of environmental factors and combinations can be involved in triggering onset of an autoimmune disease (Arleevskaya et al., 2016; Arleevskaya et al., 2020). For example, Epstein-Barr virus (EBV) is suspected of a role in autoimmune diseases, especially multiple sclerosis (MS) (Bjornevik et al., 2022). However, almost all adults have had exposure to EBV but only a small percentage develop MS and onset can be many years after initial infection with EBV. It may be that another environmental factor and/or a genetic risk allele needs to be involved, such as an especially heavy cellular viral load of EBV that may occur by viral binding and entry using HLA-DR cell surface proteins as opposed to other HLA types (Agostini et al., 2018). Research into the involvement of epigenetics in autoimmune diseases has been steadily increasing in the past two decades. Epigenetics is the control of gene expression or suppression without changing the underlying DNA sequence of the gene (Renaudineau et al., 2011). Epigenetics can involve methylation of DNA, which typically suppresses the underlying gene, or demethylation of the DNA as a step towards expression (Fali et al., 2014). Coordinated with the DNA methylation state are

International audience; In their recent article, Yang et al. reported reduced COVID-19 severity after sotrovimab infusion in solid-organ-transplant (SOT) recipients with SARS-CoV-2 infection. Since the emergence of the BA.2 omicron subvariant, this monoclonal antibody (mAb) therapy is no longer used in France due to its low neutralizing activity against BA.2 and its capacity to induce resistance-associated spike mutations. A new combination of two mAbs, tixagevimab-cilgavimab, has recently been authorized in France as an emergency treatment of SARS-CoV-2 BA.2 infections in patients at risk of severe COVID-19. While this association has been shown to protect against severe COVID-19 infections, little is known of its capacity to provoke spike mutations in the virus due to selective pressure.

International audience; Increased mortality due to SARS-CoV-2 infection was observed among solid organ transplant patients. During the pandemic, in order to prevent and treat COVID-19 infections in this context, several innovative procedures and therapies were initiated within a short period of time. A large number of these innovations can be applied and expanded to improve the management of non-COVID-19 infectious diseases in solid organ transplant patients and in the case of a future pandemic. In this vein, the present paper reviews and discusses medical care system adaptation, modification of immunosuppression, adjuvant innovative therapies, the role of laboratory expertise, and the prevention of infections as examples of such innovations.

The ability of immune-modulating biologics to prevent and reverse pathology has transformed recent clinical practice. Full utility in the neuroinflammation space, however, requires identification of both effective targets for local immune modulation and a delivery system capable of crossing the blood-brain barrier. The recent identification and characterization of a small population of regulatory T (Treg) cells resident in the brain presents one such potential therapeutic target. Here, we identified brain interleukin 2 (IL-2) levels as a limiting factor for brain-resident Treg cells. We developed a gene-delivery approach for astrocytes, with a small-molecule on-switch to allow temporal control, and enhanced production in reactive astrocytes to spatially direct delivery to inflammatory sites. Mice with brain-specific IL-2 delivery were protected in traumatic brain injury, stroke and multiple sclerosis models, without impacting the peripheral immune system. These results validate brain-specific IL-2 gene delivery as effective protection against neuroinflammation, and provide a versatile platform for delivery of diverse biologics to neuroinflammatory patients. The work was supported by the VIB, an ERC Consolidator Grant TissueTreg (to A.L.), an ERC Proof of Concept Grant TreatBrainDamage (to A.L.), an ERC Starting Grant AstroFunc (to M.G.H.), an ERC Proof of Concept Grant AD-VIP (to M.G.H.), FWO Research Grant 1513616N (to M.G.H.), Thierry Latran Foundation Grant SOD-VIP (to M.G.H.), an ERNAET Chair (H2020-WIDESPREAD-2018-2020-6; NCBio: 951923; to M.G.H.), FWO Research Grants 1503420N (to E.P.) and 1513020N (to J.W.), an SAO-FRA pilot grant (20190032, to E.P.), and the Biotechnology and Biological Sciences Research Council through Institute Strategic Program Grant funding BBS/E/B/000C0427 and BBS/E/B/000C0428, and the Biotechnology and Biological Sciences Research Council Core Capability Grant to the Babraham Institute. E.P., V.L., M.M., P.G., J.W. and A.d.B. were supported by fellowships from the FWO. R.L. is a senior clinical investigator of FWO Flanders. P.B., O.A. and C.P.F. were supported by an ERA-NET-NEURON grant EJTC 2016 to C.P.F. and by the Netherlands Organization for Scientific research (NWO). The authors acknowledge the important contributions of J. Haughton (VIB) for mouse husbandry, M. Rincon (VIB) for advice on AAV design and production, K. Vennekens for technical support, P. -A. Penttila and the KUL FACS Core, J. Wouters and the KUL Molecular Small Animal Imaging Center (MoSAIC), S. Walker and the Babraham Institute Imaging Core, the VIB Bio-Imaging Core, the VIB Single Cell Sequencing Core, and R. Breedijk, M. Hink and the Leeuwenhoek Center for Advanced Microscopy at the University of Amsterdam.

BackgroundAutoimmune encephalitis (AIE) is an increasingly broad nosological framework that may clinically mimic neurodegenerative diseases (NDDs).Cases ReportedWe describe here the clinical, radiological, electrophysiological, and biological evolution of three patients. Two women aged 73 and 72 years and a 69-year-old man presented with complex cognitive and focal neurological symptoms and each had a predominant frontal dysexecutive involvement and an unexpectedly high titer of anti-MAG antibodies in the serum and cerebrospinal fluid (CSF). The question of an autoimmune cause was raised. After 2 years of follow-up and, for two of them, without improvement despite immunosuppressive treatments, diagnoses of NDD were eventually retained: post-radiation encephalopathy, progressive supranuclear palsy (PSP), and Alzheimer's disease.ConclusionThe presence of a high titer of anti-MAG antibodies may be found in NDD. It could reflect cerebral tissue damages, particularly in the case of significant frontal involvement. Atypical presentations may lead to a search for a paraneoplastic neurologic syndrome or AIE. However, the indirect immunofluorescence staining positivity on a monkey cerebellum section linked with anti-MAG antibodies should not lead to those diagnoses being retained.

Given their well-known antifungal abilities, species of the genus Trichoderma are of significant interest in modern agriculture. Recent studies have shown that Trichoderma species can induce plant resistance against different phytopathogens. To further extend this line of investigation, we investigate herein the transcriptomic response of grapevine trunk to Vintec®, which is a Trichoderma atroviride SC1-based commercial formulation for biological control of grapevine trunk diseases and which reduces wood colonization. The aim of the study is to understand whether the biocontrol agent Vintec® modifies the trunk response to Phaeoacremonium minimum and Phaeomoniella chlamydospora, which are two esca-associated fungal pathogens. An analysis of transcriptional regulation identifies clusters of co-regulated genes whose transcriptomic reprogramming in response to infection depends on the absence or presence of Vintec®. On one hand, the results show that Vintec® differentially modulates the expression of putative genes involved in hormonal signaling, especially those involved in auxin signaling. On the other hand, most significant gene expression modifications occur among secondary-metabolism-related genes, especially regarding phenylpropanoid metabolism and stilbene biosynthesis. Taken together, these results suggest that the biocontrol agent Vintec® induces wood responses that counteract disease development.

Erythemato-ceruminous otitis externa (ECOE) is the most common type of otitis in dogs and is generally associated with bacterial and/or yeast infections. The performance of an ear cleaner was assessed over two weeks in canine ECOE, associated with a mild or moderate secondary infection, in a prospective open-label study. Forty ear canals with ECOE that did not receive any type of aural treatment and were not cleaned for 7 days were included. Pruritus (PS), 0–3 Otitis Index Score (OTIS-3) and 0–4 scale cytology (CYTO) scores were assessed on Day (D) 0, D7 and D14. Concentrations of a panel of 13 cytokines on the ear canal surface and the lipid profile of the exudate were measured on D0 and D14. From D0 to D12 or D13, the dogs’ ears were cleaned daily if the secretion score (SEC) was 3/3, every second day if the score was 2/3 and every third day if the score was 1/3. PS, OTIS-3, SEC and CYTO were significantly lower on D7 compared to baseline (−40%, −31%, −36%, −34%, respectively; p < 0.0001). The same parameters decreased further on D14 (−60%, −53%, −61%, −73%, respectively; p < 0.0001) and amounts of interleukin 8 and chemokine KC-like were also reduced compared to baseline (−45%, p < 0.01; −36%, p = 0.3, respectively). The lipid profile was also modified, with a decrease in free lipids and an increase in bound lipids.

International audience; We read with interest the letter published recently by Costa et al. in the journal of Infection. They analyzed the difference between the viral loads of the SARS-CoV-2 Alpha and Delta variants using the parameters of clinical presentation, time to testing from symptoms onset, age and vaccination status.1 A new variant of concern (VOC), the Omicron variant (B.1.1.529), emerged in South Africa in November 2021, and rapidly spread throughout the world.2 Recent data suggest that this variant is more transmissible,3 less sensitive to vaccination,4 and causes less severe outcomes than the Delta variant.5 In vitro studies have demonstrated changes in cell entry and cellular tropism with the Omicron variant that might explain its greater transmissibility and reduced severity.6,7 However, clinical data comparing Delta and Omicron infections remain scarce, especially for ambulatory patients. We therefore examined the virological features of these two variants found in patients attending testing center.

International audience; The whole world has been struggling to cope with the SARS-CoV-2 pandemic since the beginning of 2020.The measures initially used to combat the epidemic were nonpharmaceutical, such as physical distancing, mask wearing, tightened basic hygiene, quarantine, and even curfews. These measures were applied, accepted, and effective to varying degrees, depending on the country.Their application did reduce the transmission of SARS-CoV-2 and decreased the virus reproductive number R0. However, the epidemic flared up from time to time and new waves of epidemic appeared, undoubtedly due to noncompliance and/or the partial lifting of containment measures such as curfews and movement restriction.

International audience; Patients with chronic kidney disease (CKD), particularly those undergoing hemodialysis (HD), are at high risk of a severe form of coronavirus disease 2019 (COVID-19). Recently we showed that an elevated neutrophil: lymphocyte ratio at day 7 of COVID-19 predicted outcome in adult HD patients. Elevated serum C reactive protein (CRP) and ferritin were also hallmarks of the disease, confirming that, similar to all COVID-19 patients, hyperinflammation and iron disorder are also present in HD patients. Here we additionally explored hepcidin, the master regulator of iron homeostasis that has rarely been measured in COVID-19 and interleukin-6 (IL-6), the cytokine that stimulates hepcidin in inflammatory conditions.

International audience; The B.1.1.529 SARS-CoV-2 lineage, named Omicron, was recently divided into three lineages (BA.1, BA.2 and BA.3). BA.1 and BA.2 are much more dominant than BA.3. BA.1 could cause breakthrough infections in highly immune populations [1]. Preliminary studies indicate that BA.2 can readily overcome the immunity provided by vaccination and/or infection with an earlier variant. We used data for the French city of Toulouse to evaluate the impact of the proportions of the BA.1 and BA.2 variants in positive-testing samples and the impact of vaccination on SARS-CoV-2 proliferation.

International audience; Background: Two doses of anti-SARS-CoV-2 mRNA-based vaccines are poorly immunogenic in solid organ transplant recipients (SOT). Methods: In total, 68 belatacept-treated SOT recipients followed at the Toulouse University Hospital were investigated. They were given three injections of the BNT162b2 mRNA COVID-19 vaccine. Their humoral response was assessed by determining anti-spike antibodies and neutralizing antibodies. The T-cell responses were assessed using an enzyme-linked immunospot assay that measured the interferon-γ produced by specific SARS-CoV-2 T-cells in a subgroup of 17 patients. Results: Only 23.5% of these patients developed a detectable anti-spike response. Moreover, the cellular and the humoral responses were well correlated. Patients with no humoral response were also without a detectable cellular response. Those belatacept-treated patients who developed an anti-SARS-CoV-2 humoral response were younger, had been transplanted for longer, and had a higher lymphocyte count and a better glomerular filtration rate than those with no response. Finally, patients on tacrolimus plus belatacept produced a lower immune response. Conclusions: Belatacept-treated SOT recipients have a reduced immune response to anti-SARS-CoV-2 mRNA vaccination. The vaccine should be given quite separately from the belatacept infusion to improve immunogenicity. Studies to assess whether switching to another immunosuppressive regimen can improve the post-vaccination immune response would be useful.

Cutaneous cytokines and chemokines are involved in the pathogenesis of human and canine atopic dermatitis. The aim of the present study was to discriminate cytokine expression in the ear canals of atopic dogs with otitis, dogs with non-allergic inflammatory otitis (otodectic mange) and healthy non-atopic dogs. The ear canals of nine atopic dogs suffering from non-infected otitis externa (n = 14 ears), 10 healthy dogs suffering from otodectic mange (n = 20 ears) and 21 healthy controls (39 ears) were swabbed. The concentrations of a panel of 13 cytokines and chemokines on the aural surface were measured by multiplex analyses (Milliplex Canine Cytokine Panel). In addition, Canine Atopic Dermatitis Extent and Severity Index (CADESI)-04 and Otitis Index Score (OTIS3) scores were used to evaluate the overall status of the dogs. The concentration of IL-8 was significantly higher in the ears of atopic dogs and dogs with otodectic mange compared to those of healthy dogs. Significant increases in the levels of IL-10 were also overexpressed in atopic otitis but at lower rates. The concentrations of interleukin(IL)-8 were positively correlated with the OTIS3 hyperplasia score in atopic dogs. Taken together, these results suggest that IL-8 is overexpressed in atopic otitis and otodectic mange and that levels correlate with the otitis severity in atopic dogs.

BACKGROUND: The rapid development and universal access to vaccines represent a milestone in combating the coronavirus disease 2019 (COVID-19) pandemic. However, there are major concerns about vaccine response in immunocompromised populations in particular transplant recipients. In the present study, we aim to comprehensively assess the humoral response to COVID-19 vaccination in both orthotopic organ transplant and allogeneic hematopoietic stem cell transplant recipients.METHODS: We performed a systematic review and meta-analysis of 96 studies that met inclusion criteria.RESULTS: The pooled rates of seroconversion were 49% (95% confidence interval [CI], 43%-55%) in transplant recipients and 99% (95% CI, 99%-99%) in healthy controls after the second dose of vaccine. The pooled rate was 56% (95% CI, 49%-63%) in transplant recipients after the third dose. Immunosuppressive medication is the most prominent risk factor associated with seroconversion failure, but different immunosuppressive regimens are associated with differential outcomes in this respect. Calcineurin inhibitors, steroids, or mycophenolate mofetil/mycophenolic acid are associated with an increased risk of seroconversion failure, whereas azathioprine or mammalian target of rapamycin inhibitors do not. Advanced age, short interval from receiving the vaccine to the time of transplantation, or comorbidities confers a higher risk for seroconversion failure.CONCLUSIONS: Transplant recipients compared with the general population have much lower rates of seroconversion upon receiving COVID-19 vaccines. Immunosuppressants are the most prominent factors associated with seroconversion, although different types may have differential effects.

Patients with Wiskott–Aldrich syndrome (WAS) lacking a human leukocyte antigen-matched donor may benefit from gene therapy through the provision of gene-corrected, autologous hematopoietic stem/progenitor cells. Here, we present comprehensive, long-term follow-up results (median follow-up, 7.6 years) (phase I/II trial no. NCT02333760) for eight patients with WAS having undergone phase I/II lentiviral vector-based gene therapy trials (nos. NCT01347346 and NCT01347242), with a focus on thrombocytopenia and autoimmunity. Primary outcomes of the long-term study were to establish clinical and biological safety, efficacy and tolerability by evaluating the incidence and type of serious adverse events and clinical status and biological parameters including lentiviral genomic integration sites in different cell subpopulations from 3 years to 15 years after gene therapy. Secondary outcomes included monitoring the need for additional treatment and T cell repertoire diversity. An interim analysis shows that the study meets the primary outcome criteria tested given that the gene-corrected cells engrafted stably, and no serious treatment-associated adverse events occurred. Overall, severe infections and eczema resolved. Autoimmune disorders and bleeding episodes were significantly less frequent, despite only partial correction of the platelet compartment. The results suggest that lentiviral gene therapy provides sustained clinical benefits for patients with WAS., Long-term monitoring of patients with Wiskott–Aldrich syndrome following lentiviral gene therapy shows a safe profile and a reduction in the frequency of autoimmune manifestations and bleeding events, despite incomplete platelet reconstitution.

International audience; The SARS-CoV-2 B.1.1.529 (Omicron) variant, divided in five lineages (BA.1/BA.2/BA.3/BA.4/BA.5), harbors numerous spike protein mutations particularly in the receptor-binding domain (RBD). Recent studies showed that the Omicron variant resists the majority of RBD-targeting monoclonal antibodies (mAb). Sotrovimab, a pan-sarbecovirus neutralizing mAb recently authorized, seems to remain efficient to neutralize the omicron variant. However, as it targets a single epitope, the risk of developing resistance mutations is not negligible. We determined the evolution of the virus load, the development of spike mutations, and the evolution of the virus complexity in nasopharyngeal (NP) swabs from sotrovimab-treated ambulatory Omicron-infected patients.

International audience; Intradialytic hypotension (IDH) is one of the most frequent and worrying issues in chronic hemodialysis. Systolic blood pressure (BP)

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in December 2019 and caused a dramatic pandemic. Serological assays are used to check for immunization and assess herd immunity. We evaluated commercially available assays designed to quantify antibodies directed to the SARS-CoV-2 Spike (S) antigen, either total (Wantaï SARS-CoV-2 Ab ELISA) or IgG (SARS-CoV-2 IgG II Quant on Alinity, Abbott, and Liaison SARS-CoV-2 TrimericS IgG, Diasorin). The specificities of the Wantaï, Alinity, and Liaison assays were evaluated using 100 prepandemic sera and were 98, 99, and 97%, respectively. The sensitivities of all three were around 100% when tested on 35 samples taken 15 to 35 days postinfection. They were less sensitive for 150 sera from late infections (>180 days). Using the first WHO international standard (NIBSC), we showed that the Wantai results were concordant with the NIBSC values, while Liaison and Alinity showed a proportional bias of 1.3 and 7, respectively. The results of the 3 immunoassays were significantly globally pairwise correlated and for late infection sera (P < 0.001). They were correlated for recent infection sera measured with Alinity and Liaison (P < 0.001). However, the Wantai results of recent infections were not correlated with those from Alinity or Liaison. All the immunoassay results were significantly correlated with the neutralizing antibody titers obtained using a live virus neutralization assay with the B1.160 SARS-CoV-2 strain. These assays will be useful once the protective anti-SARS-CoV-2 antibody titer has been determined. IMPORTANCE Standardization and correlation with virus neutralization assays are critical points to compare the performance of serological assays designed to quantify anti-SARS-CoV-2 antibodies in order to identify their optimal use. We have evaluated three serological immunoassays based on the virus spike antigen that detect anti-SARS-CoV-2 antibodies: a microplate assay and two chemiluminescent assays performed with Alinity (Abbott) and Liaison (Diasorin) analysers. We used an in-house live virus neutralization assay and the first WHO international standard to assess the comparison. This study could be useful to determine guidelines on the use of serological results to manage vaccination and treatment with convalescent plasma or monoclonal antibodies.

Hepatitis E virus (HEV) is the first cause of viral hepatitis in the world. While the water-borne HEV genotypes 1 and 2 are found in developing countries, HEV genotypes 3 and 4 are endemic in developed countries due to the existence of animal reservoirs, especially swine. An HEV infection produces many extra-hepatic manifestations in addition to liver symptoms, especially neurological disorders. The most common are neuralgic amyotrophy or Parsonage–Turner syndrome, Guillain–Barré syndrome, myelitis, and encephalitis. The pathophysiology of the neurological injuries due to HEV remains uncertain. The immune response to the virus probably plays a role, but direct virus neurotropism could also contribute to the pathophysiology. This review describes the main neurological manifestations and their possible pathogenic mechanisms.

International audience; We read with real enthusiasm the paper by Hoertel et al. showing an “association between antidepressant use and reduced risk of intubation or death in hospitalized patients with COVID-19”. Their observation reinforces preliminary data of a double-blind, randomized clinical trial showing significant reduction of COVID-19 worsening in outpatients treated with fluvoxamine. By the time those promising results should obviously stimulate organization of large randomized clinical trials on the use of antidepressants in the fight against COVID-19, we want to plead for introducing rimonabant combined to an antidepressant in some of those trials as well as in preclinical studies.

International audience; The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is the causal agent of the COVID-19 pandemic that emerged in late 2019. The outbreak of variants with mutations in the region encoding the spike protein S1 sub-unit that can make them more resistant to neutralizing or monoclonal antibodies is the main point of the current monitoring. This study examines the feasibility of predicting the variant lineage and monitoring the appearance of reported mutations by sequencing only the region encoding the S1 domain by Pacific Bioscience Single Molecule Real-Time sequencing (PacBio SMRT). Using the PacBio SMRT system, we successfully sequenced 186 of the 200 samples previously sequenced with the Illumina COVIDSeq (whole genome) system. PacBio SMRT detected mutations in the S1 domain that were missed by the COVIDseq system in 27/186 samples (14.5%), due to amplification failure. These missing positions included mutations that are decisive for lineage assignation, such as G142D (n = 11), N501Y (n = 6), or E484K (n = 2). The lineage of 172/186 (92.5%) samples was accurately determined by analyzing the region encoding the S1 domain with a pipeline that uses key positions in S1. Thus, the PacBio SMRT protocol is appropriate for determining virus lineages and detecting key mutations.

The germinal centre (GC) is required for the generation of high affinity antibodies and immunological memory. Here we show that the RNA binding protein HuR has an essential function in GC B cells to sustain the GC response. In its absence, the GC reaction and production of high-affinity antibody is severely impaired. Mechanistically, HuR affects the transcriptome qualitatively and quantitatively. The expression and splicing patterns of hundreds of genes are altered in the absence of HuR. Among these genes, HuR is required for the expression of Myc and a Myc-dependent transcriptional program that controls GC B cell proliferation and Ig somatic hypermutation. Additionally, HuR regulates the splicing and abundance of mRNAs required for entry into and transition through the S phase of the cell cycle, and it modulates a gene signature associated with DNA deamination protecting GC B cells from DNA damage and cell death., Germinal centre (GC) responses may require RNA binding proteins (RBP) for post-transcriptional gene regulation. Here the authors show the RBP HuR supports GCs by promoting Myc and Myc-dependent transcription to enhance antigen-specific GC B cell selection and production of high affinity antibodies.

International audience; γδ T cells are activated in viral, bacterial and parasitic infections. Among viruses that promote γδ T cell mobilisation in humans, herpes viruses (HHVs) occupy a particular place since they infect the majority of the human population and persist indefinitely in the organism in a latent state. Thus, other infections should, in most instances, be considered co-infections, and the reactivation of HHV is a serious confounding factor in attributing γδ T cell alterations to a particular pathogen in human diseases. We review here the literature data on γδ T cell mobilisation in HHV infections and co-infections, and discuss the possible contribution of HHVs to γδ alterations observed in various infectious settings. As multiple infections seemingly mobilise overlapping γδ subsets, we also address the concept of possible cross-protection.

International audience; Solid-organ transplant (SOT) patients are at high risk of developing severe coronavirus disease-19 (COVID-19). Neutralizing monoclonal antibodies that bind to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein prevent viral attachment to ACE2 receptor. When administered to immunocompetent patients in the early phase of infection, they reduce the risk of hospitalization and improved symptoms resolution. Similar data were reported in a real-life study that included 69 immunosuppressed patients. However, the proportion of SOT patients and their specific outcome were not reported. Dhand et al reported encouraging results in SOT patients given bamlanivimab monotherapy or casirivimab/imdevimab without a control group.

International audience; The hepatitis A virus (HAV) is a leading cause of acute viral hepatitis worldwide. It is transmitted mainly by direct contact with patients who have been infected or by ingesting contaminated water or food. The virus is endemic in low-income countries where sanitary and sociodemographic conditions are poor. Paradoxically, improving sanitary conditions in these countries, which reduces the incidence of HAV infections, can lead to more severe disease in susceptible adults. The populations of developed countries are highly susceptible to HAV, and large outbreaks can occur when the virus is spread by globalization and by increased travel and movement of foodstuffs. Most of these outbreaks occur among high-risk groups: travellers, men who have sex with men, people who use substances, and people facing homelessness. Hepatitis A infections can be prevented by vaccination; safe and effective vaccines have been available for decades. Several countries have successfully introduced universal mass vaccination for children, but high-risk groups in high-income countries remain insufficiently protected. The development of HAV antivirals may be important to control HAV outbreaks in developed countries where a universal vaccination programme is not recommended.

International audience; Hepatitis E virus (HEV) infection can lead to a variety of neurological disorders. While HEV RNA is known to be present in the central nervous system, HEV quasispecies in serum and cerebrospinal fluid (CSF) have rarely been explored. We studied the virus’ quasispecies in the blood and the CSF of five patients at the onset of their neurological symptoms. The samples of three patients suffering from meningitis, neuralgic amyotrophy and acute inflammatory polyradiculoneuropathy were taken at the acute phase of the HEV infection. The samples from the other two patients were taken during the chronic phase (5 years after HEV diagnosis) when they presented with clinical signs of encephalitis. We sequenced at least 20 randomly polyproline regions of the selected virus clones. Phylogenetic analysis of the virus variants in the blood and the CSF revealed no virus compartmentalization for the three acute-phase patients but there was clear evidence of HEV quasispecies compartmentalization in the CSF of the two patients during chronic infection. In conclusion, prolonged infection in the immunocompromised condition can lead to independent virus replication in the liver and the tissues, producing viruses in CSF.

International audience; Background: Hepatitis E Virus (HEV) is one of the most common causes of hepatitis worldwide, and South-Western France is a high HEV seroprevalence area. While most cases of HEV infection are associated with the species Orthohepevirus-A, several studies have reported a few cases of HEV infections due to Orthohepevirus-C (HEV-C) that usually infects rats. Most of these human cases have occurred in immunocompromised patients. We have screened for the presence of HEV-C in our region. Methods and Results: We tested 224 sera, mostly from immunocompromised patients, for HEV-C RNA using an in-house real time RT-PCR. Liver function tests gave elevated results in 63% of patients: mean ALT was 159 IU/L (normal < 40 IU/L). Anti-HEV IgG (49%) and anti-HEV IgM (9.4%) were frequently present but none of the samples tested positive for HEV-C RNA. Conclusion: HEV-C does not circulate in the human population of South-Western France, despite the high seroprevalence of anti-HEV IgG.

International audience; Background: Recipients of solid organ transplant (SOT) are a high-risk group for severe SARS-CoV-2 infection. The mortality rate of patients with SOT during the COVID-19 pandemic has been reported to be approximately 20% (1). The anti–SARS-CoV-2 vaccines represent a hope to protect this population against this life-threatening infection.Objective: To assess the humoral response to messenger RNA (mRNA)–based vaccination in recipients of SOT.Methods: All patients with heart, kidney, liver, or pancreas transplants from the Midi-Pyrénées region (southwest France) are followed in our department. When the vaccination campaign started (7 January 2021), these patients were invited via text message, e-mail, or transplant patients' associations to be vaccinated. Patients were asked to register via a dedicated telephone number or website. They were vaccinated consecutively according to their registration date. According to the recommendations of the Francophone Society of Transplantation, anti–SARS-CoV-2 spike protein antibodies were monitored before and after vaccination. We used the SARS-CoV-2 total antibodies enzyme-linked immunosorbent assay test (Beijing Wantai Biological Pharmacy Enterprise) (80% of patients) or another validated anti–SARS-CoV-2 spike protein assay. According to French law (loi Jardé), anonymous retrospective studies do not require institutional review board approval.Findings: By 16 April 2021, 950 patients of the 2666 from our cohort had received at least 1 dose of an mRNA vaccine (BNT162b2 vaccine [Pfizer-BioNTech], n = 942; mRNA-1273 vaccine [Moderna], n = 8) and had anti–SARS-CoV-2 antibodies monitored. Fifty patients had vaccination without monitoring of antibodies, 80 patients are planned to be vaccinated within the next month, and 257 patients declined the vaccine. We had no feedback from the remaining 1329 patients.

International audience; A weak immune response to two doses of vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been observed in recipients of solid-organ transplants. Severe cases of coronavirus disease 2019 (Covid-19) have also been reported in transplant recipients who had received two doses of vaccine. These reports prompted the French National Authority for Health to recommend the use of a third dose in immunosuppressed patients. Here, we report the humoral response in a group of 101 consecutive solid-organ transplant recipients (mean [±SD] age, 58±2 years; 69% were men) who were given three doses of the messenger RNA vaccine BNT162b2 (Pfizer–BioNTech). The group included 78 kidney-transplant recipients, 12 liver-transplant recipients, 8 lung-transplant or heart-transplant recipients, and 3 pancreas-transplant recipients.

The host lymphocyte response is decisive in Pneumocystis pneumonia (PCP) pathophysiology but little is known of the specific roles of lymphocyte subpopulations in this fungal infection. Peripheral NK, NKT, B, TCD4+ and TCD8+ subpopulations were compared by immunophenotyping between 20 patients diagnosed with PCP (PCP(+)] and 20 uninfected immunosuppressed patients (PCP(−)). Among PCP(+) subjects, the lymphocyte populations were also compared between surviving and deceased patients. Low B cell count (&lt, 40 cells/µL) was more frequent in PCP(+) than in PCP(−) patients (p = 0.03), while there was no difference for the TCD4 count. Among the PCP(+) group, the 7 deceased patients had lower Th1 (p = 0.02) and Tc1 (p = 0.03) populations, higher Th2 response (p = 0.03), higher effector TCD8 (p &lt, 0.01), lower central memory TCD8 (p = 0.04) and reduced NK cells (p = 0.02) compared with the 13 survivors. Th1/Th2 ratio &lt, 17, CD8 Tc1 &lt, 44%, effector TCD8 &lt, 25%, central memory TCD8 &lt, 4%, NK cells &lt, 50 cells/µL and total lymphocytes &lt, 0.75 G/L were associated with a higher risk of mortality (p = 0.003, p = 0.007, p = 0.0007, p = 0.004, p = 0.02 and p = 0.019, respectively). The traditional analysis of TCD4 and TCD8 populations may be insufficient in the context of PCP. It could be completed by using B cells to predict the risk of PCP, and by using lymphocyte subpopulations or total lymphocyte count, which are easy to obtain in all health care facilities, to evaluate PCP prognosis.

The ability of phenolic compounds to autofluoresce upon illumination by UV or blue light was exploited to explore the nature and distribution of these metabolites within the flower petals, leaves and roots of the violet, Viola alba subsp. dehnhardtii. This was achieved through a dual complementary approach that combined fluorescence microscopy imaging of living intact tissues and chemical extraction of pulverized material. The blue to red fluorescence displayed by living tissues upon illumination was indicative of their richness in phenolic compounds. Phenolic acids were found in all tissues, while flavonoids characterized the aerial part of the plant, anthocyanidins being restricted to the petals. The chemical quantification of phenolics in plant extracts confirmed their tissue-specific distribution and abundance. A key finding was that the spectral signatures obtained through confocal microscopy of endogenous fluorophores in living tissues and their counterpart extracts share the same fluorescence patterns, pointing out the potential of fluorescence imaging of intact organs for a proper estimation of their phenolic content. In addition, this study highlighted a few distinct morphology cell types, in particular foliar-glandular-like structures, and jagged petal cell walls. Altogether, these data provide a comprehensive histochemical localization of phenolics in living tissues of a violet. Converting fluorescence imaging into a chemical imprint indicated that one can rely on fluorescence microscopy of intact living tissues as a rapid, non-destructive means to follow their phenolic imprint under various environmental conditions., The Parma violet Viola alba subsp. dehnhardtii distinguishes from other violets by the presence of double chasmogame flowers harbouring up to 40 petals. The phenolic imprint of its different plant parts was characterized by a dual approach that combines fluorescence imaging of living tissues and chemical analysis. The knowledge gained from this study indicated that one can rely on fluorescence microscopy as a rapid, non-destructive means to follow the phenolic pattern of a given organ or tissue. It also highlighted a few distinct morphology cell types, most notably foliar-glandular-like structures, and jagged petal cell walls.

International audience; A weak humoral response to two-doses of SARS-CoV-2 vaccine was observed in solid organ transplant (SOT) patients. Preliminary reports suggested the usefulness of a boost with a third dose. Herein, we report the humoral response in 396 SOT patients (mean age 59 ± 15 years, 65% men) who were given three doses messenger RNA-based vaccine (BNT162b2 vaccine [Pfizer-BioNTech]) (Table S1). Of these, 101 were included in our previous report.3 The two first doses were given one month apart, and the third dose was administered 59 (IQR25-75: 47–67) days after the second dose, that is, once the third dose was recommended by the French National Authority for Health. Anti-SARS-CoV-2 spike protein total antibodies were assessed the day of vaccination before the injection using either the Wantai enzyme-linked immunosorbent assay test (Beijing Wantai Biological Pharmacy Enterprise) (228 patients, 57.6%), or another anti-SARS-CoV-2 spike protein assay (n = 168) (Table S2). According to French law (loi Jardé), anonymous retrospective studies do not require institutional review board approval.

Background Prader–Willi syndrome is a rare genetic neurodevelopmental disorder caused by a paternal deficiency of maternally imprinted gene expression located in the chromosome 15q11–q13 region. Previous studies have demonstrated that several classes of neurodevelopmental disorders can be attributed to either over- or under-expression of specific genes that may lead to impairments in neuronal generation, differentiation, maturation and growth. Epigenetic changes that modify gene expression have been highlighted in these disorders. One recent study focused on epigenetic analysis and compared patients with PWS with patients with other imprinting disorders. No study, however, has yet focused on epigenetics in patients with PWS specifically by comparing the mutations associated with this syndrome. Objective This study investigated the epigenetic modifications in patients with PWS and patients with PWS-related disorders caused by inactivation of two genes of the PWS chromosomal region, SNORD116 and MAGEL2. Our approach also aimed to compare the epigenetic modifications in PWS and PWS-related disorders. Methods We compared genome-wide methylation analysis (GWAS) in seven blood samples from patients with PWS phenotype (five with deletions of the PWS locus, one with a microdeletion of SNORD116 and one with a frameshift mutation of MAGEL2 presenting with Schaaf–Yang syndrome), as well as two control patients. Controls were infants that had been studied for suspicion of genetic diseases that was not confirmed by the genetic analysis and the clinical follow-up. Results The analysis identified 29,234 differentially methylated cytosines, corresponding to 5,308 differentially methylated regions (DMRs), which matched with 2,280 genes. The DMRs in patients with PWS were associated with neurodevelopmental pathways, endocrine dysfunction and social and addictive processes consistent with the key features of the PWS phenotype. In addition, the separate analysis for the SNORD116 and MAGEL2 deletions revealed that the DMRs associated with the SNORD116 microdeletion were found in genes implicated in metabolic pathways and nervous system development, whereas MAGEL2 mutations mostly concerned genes involved in macromolecule biosynthesis. Conclusion The PWS is associated with epigenetic modifications with differences in SNORD116 and MAGEL2 mutations, which seem to be relevant to the different associated phenotypes.

International audience; The host immune response is critical in Pneumocystis pneumonia (PCP). Immunocompetent hosts can eliminate the fungus without symptoms, while immunodeficient hosts develop PCP with an unsuitable excessive inflammatory response leading to lung damage. From studies based on rodent models or clinical studies, this review aimed to better understand the pathophysiology of Pneumocystis infection by analysing the role of immune cells, mostly lymphocytes, according to the immune status of the infected host. Hence, this review first describes the immune physiological response in infected immunocompetent hosts that are able to eliminate the fungus. The objective of the second part is to identify the immune elements required for the control of the fungus, focusing on specific immune deficiencies. Finally, the third part concentrates on the effect of the different immune elements in immunocompromised subjects during PCP, to better understand which cells are detrimental, and which, on the contrary, are beneficial once the disease has started. This work highlights that the immune response associated with a favourable outcome of the infection may differ according to the immune status of the host. In the case of immunocompetency, a close communication between B cells and TCD4 within tertiary lymphocyte structures appears critical to activate M2 macrophages without much inflammation. Conversely, in the case of immunodeficiency, a pro-inflammatory response including Th1 CD4, cytotoxic CD8, NK cells, and IFNγ release seems beneficial for M1 macrophage activation, despite the impact of inflammation on lung tissue.

International audience; While kidney transplant recipients (KTRs) represent a high-risk population for severe SARS-CoV-2 infection, almost half of them do not develop adequate levels of antibodies conferring clinical protection despite 3 doses of the mRNA vaccine. In the present study we retrospectively analyzed the humoral and cellular responses resulting from a fourth dose of vaccine administered to KTRs having an anti-SARS-CoV-2 antibody titer below 142 binding antibody unit (BAU)/mL at 3 months post-third-dose. We observed a significant increase in anti-SARS-CoV-2 antibody concentration from 6.1 (Q1 4.3; Q3 12.7) BAU/mL on the day of the fourth dose to 1054.0 (Q1 739.6; Q3 1649.0) BAU/mL one month later (p = 0.0007), as well as neutralizing antibody titers (from 0.0 (Q1 0.0; Q3 2.0) to 8 (4; 16) IU/mL, p = 0.01) and CD3+ T cell response (from 37.5 (Q1 12.5; Q3 147.5) to 170.0 (Q1 57.5; Q3 510.0) SFUs per 106 PBMCs, p = 0.001). Hence, delaying the fourth dose seems to improve vaccine immunogenicity in KTRs, compared with previously reported data obtained in respect of a fourth dose one month after the third dose. Nevertheless, antibody concentrations seem to remain insufficient to confer clinical protection, especially for Omicron, for which breakthrough infections occur even at very high concentrations.

International audience; The actin cytoskeleton is composed of dynamic filament networks that build adaptable local architectures to sustain nearly all cellular activities in response to a myriad of stimuli. Although the function of numerous players that tune actin remodeling is known, the coordinated molecular orchestration of the actin cytoskeleton to guide cellular decisions is still ill defined. T lymphocytes provide a prototypical example of how a complex program of actin cytoskeleton remodeling sustains the spatio-temporal control of key cellular activities, namely antigen scanning and sensing, as well as polarized delivery of effector molecules, via the immunological synapse. We here review the unique knowledge on actin dynamics at the T lymphocyte synapse gained through the study of primary immunodeficiences caused by mutations in genes encoding actin regulatory proteins. Beyond the specific roles of individual actin remodelers, we further develop the view that these operate in a coordinated manner and are an integral part of multiple signaling pathways in T lymphocytes.

The SARS-CoV-2 virus has spread world-wide since December 2019, killing more than 2.9 million of people. We have adapted a statistical model from the SIR epidemiological models to predict the spread of SARS-CoV-2 in France. Our model is based on several parameters and assumed a 4.2% seroprevalence in Occitania after the first lockdown. The recent use of serological tests to measure the effective seroprevalence of SARS-CoV-2 in the population of Occitania has led to a seroprevalence around 2.4%. This implies to review the parameters of our model to conclude at a lower than expected virus transmission rate, which may be due to infectivity varying with the patient’s symptoms or to a constraint due to an uneven population geographical distribution.

International audience; Previous studies have attested that the admission of a relative to an intensive care unit (ICU) is associated with increased stress for the patient's family. Indeed, 70% of family members have been found to present with symptoms of anxiety, 35% with depressive symptoms and 33% with post-traumatic stress disorder (PTSD). Consequently, specific guidance has been produced concerning family-centered care, which is a partnership approach to decision-making involving families and health-care providers.

International audience; The spread of SARS-CoV-2 and the resulting disease Covid-19 has killed over 2 million people as of January 22, 2021. We have designed a model and used it to quantify the effect of a 6 p.m curfew on the SARS-CoV-2 epidemic in Toulouse, France. The data show that this measure can lead to the opposite effect from that intended due to larger groups of people on the authorized hours.

International audience; In order to ascertain the significance of transmembrane tumor necrosis factor (tmTNF) reverse signaling in vivo, we generated a triple transgenic mouse model (3TG, TNFR1-/-, TNFR2-/-, and tmTNFKI/KI) in which all canonical tumor necrosis factor (TNF) signaling was abolished. In bone-marrow-derived macrophages harvested from these mice, various anti-TNF biologics induced the expression of genes characteristic of alternative macrophages and also inhibited the expression of pro-inflammatory cytokines mainly through the upregulation of arginase-1. Injections of TNF inhibitors during arthritis increased pro-resolutive markers in bone marrow precursors and joint cells leading to a decrease in arthritis score. These results demonstrate that the binding of anti-TNF biologics to tmTNF results in decreased arthritis severity. Collectively, our data provide evidence for the significance of tmTNF reverse signaling in the modulation of arthritis. They suggest a complementary interpretation of anti-TNF biologics effects in the treatment of inflammatory diseases and pave the way to studies focused on new arginase-1-dependent therapeutic targets.

International audience; Treatment with asfotase alfa has transformed the prognosis of hypophosphatasia in children and improves the bone and muscle signs in adults. The doses used in adults are the same as in children, whereas bone remodeling is different between them. We report on the cases of two patients treated with 1 mg/kg/day of asfotase alfa who developed spinal cord compression from spinal ossifications during treatment. The first patient, 50 years old, presented after 2 years of treatment with quadraparesis secondary to an increase in ossifications of the cervical vertebral ligaments. The neurological damage was resolved after laminectomy, and the patient was then treated for 18 months with doses of 80 mg per week, without recurrence of the bone and muscle signs. The second patient, 26 years old, 78 kg, developed pain and cervical stiffness with pyramidal tract irritation secondary to ossifications of the vertebral ligaments. This improved with a reduction of doses to 80 mg/week, which then, after 6 months of follow-up, enabled maintained improvement of the bone and muscle pain that was initially obtained. To our knowledge, these are the first reported cases of increased spinal ligamentous ossifications with neurological complications. Biological monitoring in adults does not seem to enable asfotase alfa doses to be adjusted. The levels of serum alkaline phosphatase (ALP) while on the recommended treatment of 1 mg/kg/day are significantly supraphysiological (5000 to 20,000 IU) and the assays of pyrophosphate and pyridoxal phosphate are not correlated with clinical efficacy. In both of our patients, the treatment with 80 mg of asfotase alfa per week, which was proposed after the occurrence of spinal complications, seemed as effective, after a follow-up of 18 months and 6 months, as the initial treatment for improving the bone and muscle signs, and could be provided as “attack” doses after healing of the pseudoarthroses.

International audience; Control of the rapid spread of the SARS-CoV-2 virus requires efficient testing. We collected paired nasopharyngeal swab (NPs) and saliva samples from 303 subjects (52.8% symptomatic) at a drive-through testing center; 18% of whom tested positive. The NPs, salivas and five saliva pools were tested for SARS-CoV-2 RNA using the Aptima™ assay and a laboratory-developed test (LDT) on the Panther-Fusion™ Hologic® platform. The saliva sensitivity was 80% (LDT) and 87.5% (Aptima™) whereas that of NPs was 96.4% in both assays. The pooled saliva sensitivity of 72.7% (LDT) and 75% (Aptima™) was not significantly different of that of individual saliva testing. Saliva specimens appear to be suitable for sensitive non-invasive assays to detect SARS-CoV-2 nucleic acid; pooling them for a single test will improve laboratory throughput.

International audience; Solar ultraviolet A (UV-A) radiation promotes a huge variety of damages on connective tissues and dermal fibroblasts, including cellular senescence, a major contributor of skin photoaging. The mechanisms of skin photoaging evoked by UV-A partly involve the generation of reactive oxygen species and lipid peroxidation. We previously reported that 4-hydroxynonenal (HNE), a lipid peroxidation-derived aldehyde, forms adducts on elastin in the skins of UV-A irradiated hairless mice, possibly contributing to actinic elastosis. In the present study, we investigated whether and how HNE promotes fibroblast senescence in skin photoaging. Dermal fibroblasts of skins from UV-A-exposed hairless mice exhibited an increased number of γH2AX foci characteristic of cell senescence, together with an accumulation of HNE adducts partly colocalizing with the cytoskeletal protein vimentin. Murine fibroblasts exposed to UV-A radiation (two cycles of 15 J/cm2), or HNE (30 µM, 4 h), exhibited senescence patterns characterized by an increased γH2AX foci expression, an accumulation of acetylated proteins, and a decreased expression of the sirtuin SIRT1. HNE adducts were detected on vimentin in cultured fibroblasts irradiated by UV-A or incubated with HNE. The HNE scavenger carnosine prevented both vimentin modification and fibroblast senescence evoked by HNE in vitro and in the skins of UV-A-exposed mice. Altogether, these data emphasize the role of HNE and lipid peroxidation-derived aldehydes in fibroblast senescence, and confirm the protective effect of carnosine in skin photoaging.

Women diagnosed with high-grade serous ovarian cancers (HGSOC) are still likely to exhibit a bad prognosis, particularly when suffering from HGSOC of the Mesenchymal molecular subtype (50% cases). These tumors show a desmoplastic reaction with accumulation of extracellular matrix proteins and high content of cancer-associated fibroblasts. Using patient-derived xenograft mouse models of Mesenchymal and Non-Mesenchymal HGSOC, we show here that HGSOC exhibit distinct stiffness depending on their molecular subtype. Indeed, tumor stiffness strongly correlates with tumor growth in Mesenchymal HGSOC, while Non-Mesenchymal tumors remain soft. Moreover, we observe that tumor stiffening is associated with high stromal content, collagen network remodeling, and MAPK/MEK pathway activation. Furthermore, tumor stiffness accompanies a glycolytic metabolic switch in the epithelial compartment, as expected based on Warburg’s effect, but also in stromal cells. This effect is restricted to the central part of stiff Mesenchymal tumors. Indeed, stiff Mesenchymal tumors remain softer at the periphery than at the core, with stromal cells secreting high levels of collagens and showing an OXPHOS metabolism. Thus, our study suggests that tumor stiffness could be at the crossroad of three major processes, i.e. matrix remodeling, MEK activation and stromal metabolic switch that might explain at least in part Mesenchymal HGSOC aggressiveness.