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The organization and dynamics of chromatin within the interphase nucleus as chromosome territories ( CTs) and the relationship with transcriptional regulation are not fully understood. We studied a natural example of chromosomal disorganization: aneuploidy due to trisomies 13, 18 and 21. We hypothesized that the presence of an extra copy of one chromosome alters the CT distribution, which perturbs transcriptional activity. We used 3D-FISH to study the position of the chromosomes of interest (18 and 21) in cultured amniocytes and chorionic villus cells from pregnancies with a normal or aneuploid karyotype. We studied the volumes of nuclei and CTs in both conditions and performed a compared transcriptome analysis. We did not observe any differences between euploid and aneuploid cells in terms of the radial and relative CT positions, suggesting that the same rules govern nuclear organization in cases of trisomy. We observed lower volumes for CTs 18 and 21. Overall genome expression profiles highlighted changes in the expression of a subset of genes in trisomic chromosomes, while the majority of transcriptional changes concerned genes located on euploid chromosomes. Our results suggest that a dosage imbalance of the genes on trisomic chromosomes is associated with a disturbance of overall genomic expression. [ABSTRACT FROM AUTHOR]

Examines the function of the cytoplasmic tail of CD3 epsilon of the multichain T cell antigen receptor. How receptor functions; Role of xi chain cytoplasmic tail; Ability of CD3 epsilon cytoplasmic tail to independently activate T cells; Results of stimulation of T cells by cytoplasmic tails of xi or CD3 epsilon; Possible activation of different biochemical pathways.

Abstract Background Epicutaneous immunotherapy (EPIT) on intact skin with an epicutaneous delivery system has already been used in preclinical and clinical studies. In epicutaneous vaccination and immunotherapy, the stripping of skin before application of the allergen is suggested to facilitate the passage of allergen through immune cells. Objectives The aim of this study was to compare the immunological response induced by EPIT performed on intact and stripped skin in a mouse model of peanut allergy. Methods After oral sensitization with peanut and cholera toxin, BALB/c mice were epicutaneously treated using an epicutaneous delivery system (Viaskin® (DBV Technologies, Paris) applied either on intact skin or on stripped skin. Following EPIT, mice received an exclusive oral peanut regimen, aimed at triggering esophageal and jejunal lesions. We assessed eosinophil infiltration by histology, mRNA expression in the esophagus, antibody levels and peripheral T-cell response. Results EPIT on intact skin significantly reduced Th2 immunological response (IgE response and splenocyte secretion of Th2 cytokines) as well as esophageal eosinophilia (2.7 ± 0.9, compared to Sham 19.9 ± 1.5, p Conclusions Epicutaneous allergen-specific immunotherapy needs the integrity of superficial layers of the stratum corneum to warranty safety of treatment and to induce a tolerogenic profile of the immune response.

Abstract Background Emergence of viral variants that escape CTL control is a major hurdle in HIV vaccination unless such variants affect gene regions that are essential for virus replication. Vaccine-induced multispecific CTL could also be able to control viral variants replication. To explore these possibilities, we extensively characterized CTL responses following vaccination with an epitope-based lipopeptide vaccine and challenge with pathogenic SIVmac251. The viral sequences corresponding to the epitopes present in the vaccine as well as the viral loads were then determined in every macaque following SIV inoculation. Results In most cases, the emergence of several viral variants or mutants within vaccine CTL epitopes after SIV challenge resulted in increased viral loads except for a single macaque, which showed a single escape viral variant within its 6 vaccine-induced CTL epitopes. Conclusion These findings provide a better understanding of the evolution of CD8+ epitope variations after vaccination-induced CTL expansion and might provide new insight for the development of an effective HIV vaccine.

Abstract Background Plasmodium vivax is the second most prevalent malaria parasite affecting more than 75 million people each year, mostly in South America and Asia. In addition to major morbidity this parasite is associated with relapses and a reduction in birthweight. The emergence and spread of drug resistance in Plasmodium falciparum is a major factor in the resurgence of this parasite. P. vivax resistance to drugs has more recently emerged and monitoring the situation would be helped, as for P. falciparum, by molecular methods that can be used to characterize parasites in field studies and drug efficacy trials. Methods Practical PCR genotyping protocols based on polymorphic loci present in two P. vivax genetic markers, Pvcs and Pvmsp1, were developed. The methodology was evaluated using 100 P. vivax isolates collected in Thailand. Results and Discussion Analysis revealed that P. vivax populations in Thailand are highly diverse genetically, with mixed genotype infections found in 26 % of the samples (average multiplicity of infection = 1.29). A large number of distinguishable alleles were found for the two markers, 23 for Pvcs and 36 for Pvmsp1. These were generally randomly distributed amongst the isolates. A total of 68 distinct genotypes could be enumerated in the 74 isolates with a multiplicity of infection of 1. Conclusion These results indicate that the genotyping protocols presented can be useful in the assessment of in vivo drug efficacy clinical trials conducted in endemic areas and for epidemiological studies of P. vivax infections.

Background: In kidney transplantation, molecular diagnostics may be a valuable approach to improve the precision of the diagnosis. Using next-generation sequencing (NGS), we aimed to identify clinically relevant archetypes., Methods: We conducted an Illumina bulk RNA sequencing on 770 kidney biopsies (540 kidney recipients) collected between 2006 and 2021 from 11 European centers. Differentially expressed genes were determined for 11 Banff lesions. An ElasticNet model was used for feature selection, and 4 machine learning classifiers were trained to predict the probability of presence of the lesions. NGS-based classifiers were used in an unsupervised archetypal analysis to different archetypes. The association of the archetypes with allograft survival was assessed using the iBox risk prediction score., Results: The ElasticNet feature selection reduced the number of the genes from a range of 859-10 830 to a range of 52-867 genes. NGS-based classifiers demonstrated robust performances (precision-recall area under the curves 0.708-0.980) in predicting the Banff lesions. Archetypal analysis revealed 8 distinct phenotypes, each characterized by distinct clinical, immunological, and histological features. Although the archetypes confirmed the well-defined Banff rejection phenotypes for T cell-mediated rejection and antibody-mediated rejection, equivocal histologic antibody-mediated rejection, and borderline diagnoses were reclassified into different archetypes based on their molecular signatures. The 8 NGS-based archetypes displayed distinct allograft survival profiles with incremental graft loss rates between archetypes, ranging from 90% to 56% rates 7 y after evaluation (P < 0.0001)., Conclusions: Using molecular phenotyping, 8 archetypes were identified. These NGS-based archetypes might improve disease characterization, reclassify ambiguous Banff diagnoses, and enable patient-specific risk stratification., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Radiotherapy represents a major curative treatment for prostate cancer (PCa), but some patients will develop radioresistance (RR) and relapse. The underlying mechanisms remain poorly understood, and miRNAs might be key players in the acquisition and maintenance of RR. Through their encapsulation in small extracellular vesicles (EVs), they can also be relevant biomarkers of radiation response. Using next-generation sequencing, we found that miR-200c-3p was downregulated in PCa RR cells and in their small EVs due to a gain of methylation on its promoter during RR acquisition. We next showed that its exogenous overexpression restores the radiosensitivity of RR cells by delaying DNA repair through the targeting of HP1α. Interestingly, we also observed downregulation of miR-200c-3p expression by DNA methylation in radiation-resistant lung and breast cancer cell lines. In summary, our study demonstrates that the downregulation of miR-200c-3p expression in PCa cells and in their small EVs could help distinguish radioresistant from sensitive tumor cells. This miRNA targets HP1α to delay DNA repair and promote cell death., (© 2024. The Author(s).)

Exposure to polycyclic aromatic hydrocarbons (PAHs), ubiquitously environmental contaminant, leads to the development of major toxic effects on human health, such as carcinogenic and immunosuppressive alterations reported for the most studied PAH, i.e., benzo(a)pyrene (B(a)P). In order to assess the risk associated with this exposure, it is necessary to have predictive biomarkers. Thus, extracellular vesicles (EVs) and their microRNA (miRNA) contents, have recently been proposed as potentially interesting biomarkers in Toxicology. Our study here explores the use of vesicles secreted and found in blood fluids, and their miRNAs, as biomarkers of exposure to B(a)P alone and within a realistic occupational mixture. We isolated EVs from primary human cultured blood mononuclear cells (PBMCs) and rat plasma after PAH exposure and reported an increased EV production by B(a)P, used either alone or in the mixture, in vitro and in vivo. We then investigated the association of this EV release with the blood concentration of the 7,8,9,10-hydroxy (tetrol)-B(a)P reactive metabolite, in rats. By performing RNA-sequencing (RNA-seq) of miRNAs in PBMC-derived EVs, we analyzed miRNA profiles and demonstrated the regulation of the expression of miR-342-3p upon B(a)P exposure. We then validated B(a)P-induced changes of miR-342-3p expression in vivo in rat plasma-derived EVs. Overall, our study highlights the feasibility of using EVs and their miRNA contents, as biomarkers of PAH exposure and discusses their potential in environmental Toxicology., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Lydie SPARFEL reports financial support was provided by National Agency for Food Environmental and Occupational Health and Safety. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Loss of endothelial integrity and vascular leakage are central features of sepsis pathogenesis; however, no effective therapeutic mechanisms for preserving endothelial integrity are available. Here we show that, compared to dermal microvessels, brain microvessels resist infection by Neisseria meningitidis, a bacterial pathogen that causes sepsis and meningitis. By comparing the transcriptional responses to infection in dermal and brain endothelial cells, we identified angiopoietin-like 4 as a key factor produced by the brain endothelium that preserves blood-brain barrier integrity during bacterial sepsis. Conversely, angiopoietin-like 4 is produced at lower levels in the peripheral endothelium. Treatment with recombinant angiopoietin-like 4 reduced vascular leakage, organ failure and death in mouse models of lethal sepsis and N. meningitidis infection. Protection was conferred by a previously uncharacterized domain of angiopoietin-like 4, through binding to the heparan proteoglycan, syndecan-4. These findings reveal a potential strategy to prevent endothelial dysfunction and improve outcomes in patients with sepsis., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)

Bilateral macronodular adrenocortical disease (BMAD) is an uncommon cause of Cushing's syndrome leading to bilateral macronodules. Isolated BMAD has been classified into three molecular groups: patients with ARMC5 alteration, KDM1A alteration, and patients without known genetic cause. The aim of this study was to identify by NGS, in a cohort of 26 patients with BMAD, the somatic alterations acquired in different nodules after macrodissection from patients with germline ARMC5 or KDM1A alterations and to analyze potential somatic alterations in a panel of five other genes involved in adrenal pathology (GNAS, PDE8B, PDE11A, PRKAR1A, and PRKACA). Twenty-three patients (7 ARMC5, 3 KDM1A, and 13 BMAD with unknown genetic cause) were analyzable. Somatic ARMC5 or KDM1A events were exclusively observed in patients with germline ARMC5 and KDM1A alterations, respectively. Six out of 7 ARMC5 patients have a high heterogeneity in identified somatic events, whereas one ARMC5 and all KDM1A patients show a loss of heterozygosity (LOH) in all nodules. Except for passenger alterations of GNAS, no genetic alteration susceptible to causing the disease was detected in the BMAD with unknown genetic cause. Our study reinforces our knowledge of the somatic genetic heterogeneity of ARMC5 and the somatic homogeneity of KDM1A. It reveals the absence of purely somatic events in these two genes and provides a new tool for detecting KDM1A alterations by FISH 1p36/1q25., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Objective: Cushing's syndrome is characterized by high morbidity and mortality with high interindividual variability. Easily measurable biomarkers, in addition to the hormone assays currently used for diagnosis, could reflect the individual biological impact of glucocorticoids. The aim of this study is to identify such biomarkers through the analysis of whole blood transcriptome., Design: Whole blood transcriptome was evaluated in 57 samples from patients with overt Cushing's syndrome, mild Cushing's syndrome, eucortisolism, and adrenal insufficiency. Samples were randomly split into a training cohort to set up a Cushing's transcriptomic signature and a validation cohort to assess this signature., Methods: Total RNA was obtained from whole blood samples and sequenced on a NovaSeq 6000 System (Illumina). Both unsupervised (principal component analysis) and supervised (Limma) methods were used to explore the transcriptome profile. Ridge regression was used to build a Cushing's transcriptome predictor., Results: The transcriptomic profile discriminated samples with overt Cushing's syndrome. Genes mostly associated with overt Cushing's syndrome were enriched in pathways related to immunity, particularly neutrophil activation. A prediction model of 1500 genes built on the training cohort demonstrated its discriminating value in the validation cohort (accuracy .82) and remained significant in a multivariate model including the neutrophil proportion (P = .002). Expression of FKBP5, a single gene both overexpressed in Cushing's syndrome and implied in the glucocorticoid receptor signaling, could also predict Cushing's syndrome (accuracy .76)., Conclusions: Whole blood transcriptome reflects the circulating levels of glucocorticoids. FKBP5 expression could be a nonhormonal marker of Cushing's syndrome., Competing Interests: Conflict of interest: G.A. is on the editorial board of EJE. G.A. was not involved in the review or editorial process for this paper, on which he is listed as an author., (© The Author(s) 2024. Published by Oxford University Press on behalf of European Society of Endocrinology.)

Background: A scale for self-assessment of auditory verbal hallucinations (SAVH) was developed for patients, and this study aimed to validate the scale by investigating its psychometric properties., Methods: Forty one patients with schizophrenia or schizoaffective disorders (DSM-5) self-assessed their hallucinations using nine SAVH questions. Each question was scored from 0 to 5, indicating the severity of the symptoms. Patients were also evaluated with the Brief Psychiatric Rating Scale (BPRS), Auditory Hallucination Rating Scale (AHRS), and Birchwood Insight Scale (BIS). The psychometric properties of the SAVH were assessed by the face, internal consistency, construct, convergent and discriminant validities., Results: SAVH scores were used to examine the psychometric properties. Cronbach's α and Guttman's Lambda-6 were 0.67 and 0.73 respectively. Significant correlations were observed between SAVH and AHRS total scores, as well as BPRS hallucinatory behavior subscores. No significant correlations were found between total SAVH scores and (i) levels of insight or (ii) negative BPRS subscores. Factor analysis on SAVH revealed three factors accounting for 59.3 % of the variance. Most patients found the questions clear, appropriate, and of adequate length., Conclusions: SAVH demonstrated good psychometric properties, suggesting its utility in assessing auditory verbal hallucinations (AVH). This self-assessment could be valuable in evaluating AVH treatment efficacy, monitoring AVH, and empowering patients., Competing Interests: Declaration of competing interest The authors have declared that there are no conflicts of interest in relation to the subject of this study., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Foxo family transcription factors are critically involved in multiple processes, such as metabolism, quiescence, cell survival and cell differentiation. Although continuous, high activity of Foxo transcription factors extends the life span of some species, the involvement of Foxo proteins in mammalian aging remains to be determined. Here, we show that Foxo1 is down-regulated with age in mouse T cells. This down-regulation of Foxo1 in T cells may contribute to the disruption of naive T-cell homeostasis with age, leading to an increase in the number of memory T cells. Foxo1 down-regulation is also associated with the up-regulation of co-inhibitory receptors by memory T cells and exhaustion in aged mice. Using adoptive transfer experiments, we show that the age-dependent down-regulation of Foxo1 in T cells is mediated by T-cell-extrinsic cues, including type 1 interferons. Taken together, our data suggest that type 1 interferon-induced Foxo1 down-regulation is likely to contribute significantly to T-cell dysfunction in aged mice., (© 2024. The Author(s).)

Objective: Mesial Temporal Lobe Epilepsy-associated Hippocampal Sclerosis (MTLE-HS) is a syndrome associated with various aetiologies. We previously identified CD34-positive extravascular stellate cells (CD34+ cells) possibly related to BRAF V600E oncogenic variant in a subset of MTLE-HS. We aimed to identify the BRAF V600E oncogenic variants and characterise the CD34+ cells., Methods: We analysed BRAF V600E oncogenic variant by digital droplet Polymerase Chain Reaction in 53 MTLE-HS samples (25 with CD34+ cells) and nine non-expansive neocortical lesions resected during epilepsy surgery (five with CD34+ cells). Ex vivo multi-electrode array recording, immunolabelling, methylation microarray and single nuclei RNAseq were performed on BRAF wildtype MTLE-HS and BRAF V600E mutant non-expansive lesion of hippocampus and/or neocortex., Results: We identified a BRAF V600E oncogenic variant in five MTLE-HS samples with CD34+ cells (19%) and in five neocortical samples with CD34+ cells (100%). Single nuclei RNAseq of resected samples revealed two unique clusters of abnormal cells (including CD34+ cells) associated with senescence and oligodendrocyte development in both hippocampal and neocortical BRAF V600E mutant samples. The co-expression of the oncogene-induced senescence marker p16 INK4A and the outer subventricular zone radial glia progenitor marker HOPX in CD34+ cells was confirmed by multiplex immunostaining. Pseudotime analysis showed that abnormal cells share a common lineage from progenitors to myelinating oligodendrocytes. Epilepsy surgery led to seizure freedom in eight of the 10 patients with BRAF mutant lesions., Interpretation: BRAF V600E underlies a subset of MTLE-HS and epileptogenic non-expansive neocortical focal lesions. Detection of the oncogenic variant may help diagnosis and open perspectives for targeted therapies., (© 2023 The Authors. Neuropathology and Applied Neurobiology published by John Wiley & Sons Ltd on behalf of British Neuropathological Society.)

Non-coding RNAs (ncRNAs) are important regulators of gene expression. They are expressed not only in cells, but also in cell-derived extracellular vesicles (EVs). The mechanisms controlling their loading and sorting remain poorly understood. Here, we investigated the impact of TP53 mutations on the non-coding RNA content of small melanoma EVs. After purification of small EVs from six different patient-derived melanoma cell lines, we characterized them by small RNA sequencing and lncRNA microarray analysis. We found that TP53 mutations are associated with a specific micro and long non-coding RNA content in small EVs. Then, we showed that long and small non-coding RNAs enriched in TP53 mutant small EVs share a common sequence motif, highly similar to the RNA-binding motif of Sam68, a protein interacting with hnRNP proteins. This protein thus may be an interesting partner of p53, involved in the expression and loading of the ncRNAs. To conclude, our data support the existence of cellular mechanisms associate with TP53 mutations which control the ncRNA content of small EVs in melanoma., Competing Interests: The authors declare no competing interests., (© 2023 The Authors. Journal of Extracellular Biology published by Wiley Periodicals, LLC on behalf of the International Society for Extracellular Vesicles.)

Polycyclic aromatic hydrocarbons (PAHs) are widely distributed environmental contaminants, triggering deleterious effects such as carcinogenicity and immunosuppression, and peripheral blood mononuclear cells (PBMCs) are among the main cell types targeted by these pollutants. In the present study, we sought to identify the expression profiles and function of miRNAs, gene regulators involved in major cellular processes recently linked to environmental pollutants, in PBMC-exposed to the prototypical PAH, benzo[a]pyrene (B[a]P). Using small RNA deep sequencing, we identified several B[a]P-responsive miRNAs. Bioinformatics analyses showed that their predicted targets could modulate biological processes relevant to cell death and survival. Further studies of the most highly induced miRNA, miR-132, showed that its up-regulation by B[a]P was time- and dose-dependent and required aryl hydrocarbon receptor (AhR) activation. By evaluating the role of miR-132 in B[a]P-induced cell death, we propose a mechanism linking B[a]P-induced miR-132 expression and cytochromes P-450 (CYPs) 1A1 and 1B1 mRNA levels, which could contribute to the apoptotic response of PBMCs. Altogether, this study increases our understanding of the roles of miRNAs induced by B[a]P and provides the basis for further investigations into the mechanisms of gene expression regulation by PAHs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Host metabolism reprogramming is a key feature of Mycobacterium tuberculosis ( Mtb ) infection that enables the survival of this pathogen within phagocytic cells and modulates the immune response facilitating the spread of the tuberculosis disease. Here, we demonstrate that a previously uncharacterized secreted protein from Mtb , Rv1813c, manipulates the host metabolism by targeting mitochondria. When expressed in eukaryotic cells, the protein is delivered to the mitochondrial intermembrane space and promotes the enhancement of host ATP production by boosting the oxidative phosphorylation metabolic pathway. Furthermore, the release of cytochrome c from mitochondria, an early apoptotic event in response to short-term oxidative stress, is delayed in Rv1813c-expressing cells. This study reveals a novel class of mitochondria targeting effectors from Mtb that might participate in host cell metabolic reprogramming and apoptosis control during Mtb infections. IMPORTANCE In this article, using a combination of techniques (bioinformatics, structural biology, and cell biology), we identified and characterized a new class of effectors present only in intracellular mycobacteria. These proteins specifically target host cell mitochondria when ectopically expressed in cells. We showed that one member of this family (Rv1813c) affects mitochondria metabolism in a way that might twist the immune response. This effector also inhibits the cytochrome c exit from mitochondria, suggesting that it might alter normal host cell apoptotic capacities, one of the first defenses of immune cells against Mtb infection., Competing Interests: The authors declare no conflict of interest.

The amoeba-resistant bacterium Legionella pneumophila causes Legionnaires' disease and employs a type IV secretion system (T4SS) to replicate in the unique, ER-associated Legionella -containing vacuole (LCV). The large fusion GTPase Sey1/atlastin is implicated in ER dynamics, ER-derived lipid droplet (LD) formation, and LCV maturation. Here, we employ cryo-electron tomography, confocal microscopy, proteomics, and isotopologue profiling to analyze LCV-LD interactions in the genetically tractable amoeba Dictyostelium discoideum . Dually fluorescence-labeled D. discoideum producing LCV and LD markers revealed that Sey1 as well as the L. pneumophila T4SS and the Ran GTPase activator LegG1 promote LCV-LD interactions. In vitro reconstitution using purified LCVs and LDs from parental or Δ sey1 mutant D. discoideum indicated that Sey1 and GTP promote this process. Sey1 and the L. pneumophila fatty acid transporter FadL were implicated in palmitate catabolism and palmitate-dependent intracellular growth. Taken together, our results reveal that Sey1 and LegG1 mediate LD- and FadL-dependent fatty acid metabolism of intracellular L. pneumophila ., Competing Interests: DH, PS, BK, DB, TS, AO, SV, BS, AS, FL, SM, DB, WE, MP, HH No competing interests declared, (© 2023, Hüsler et al.)

Legionella pneumophila replicates in macrophages and amoeba within a unique compartment, the Legionella-containing vacuole (LCV). Hallmarks of LCV formation are the phosphoinositide lipid conversion from PtdIns(3)P to PtdIns(4)P, fusion with ER-derived vesicles and a tight association with the ER. Proteomics of purified LCVs indicate the presence of membrane contact sites (MCS) proteins possibly implicated in lipid exchange. Using dually fluorescence-labeled Dictyostelium discoideum amoeba, we reveal that VAMP-associated protein (Vap) and the PtdIns(4)P 4-phosphatase Sac1 localize to the ER, and Vap also localizes to the LCV membrane. Furthermore, Vap as well as Sac1 promote intracellular replication of L. pneumophila and LCV remodeling. Oxysterol binding proteins (OSBPs) preferentially localize to the ER (OSBP8) or the LCV membrane (OSBP11), respectively, and restrict (OSBP8) or promote (OSBP11) bacterial replication and LCV expansion. The sterol probes GFP-D4H* and filipin indicate that sterols are rapidly depleted from LCVs, while PtdIns(4)P accumulates. In addition to Sac1, the PtdIns(4)P-subverting L. pneumophila effector proteins LepB and SidC also support LCV remodeling. Taken together, the Legionella- and host cell-driven PtdIns(4)P gradient at LCV-ER MCSs promotes Vap-, OSBP- and Sac1-dependent pathogen vacuole maturation., (© 2022 The Authors.)

Introduction: Spondylarthritis (SpA) development in HLA-B27/human β2-microglobulin transgenic rat (B27-rat) is correlated with altered conventional dendritic cell (cDC) function that promotes an inflammatory pattern of CD4+T cells, including a biased expansion of pro-inflammatory Th 17 population and imbalance of regulatory T cells cytokine profile. Transcriptomic analysis revealed that cDCs from B27-rats under express IL-27, an anti-inflammatory cytokine which induces the differentiation of IL-10 + regulatory T cells and inhibits Th 17 cells., Methods: Here, we first investigated whether in vitro addition of exogenous IL-27 could reverse the inflammatory pattern observed in CD4 + T cells. Next, we performed preclinical assay using IL-27 to investigate whether in vivo treatment could prevent SpA development in B27-rats., Results: in vitro addition of IL-27 to cocultures of cDCs and CD4 + T cell subsets from B27-rats reduced IL-17 and enhanced IL-10 production by T cells. Likewise, IL-27 inhibited the production of IL-17 by CD4 + T cells from SpA patients. Interestingly, in vivo treatment with recombinant IL-27 starting before SpA onset, inhibited SpA development in B27-rats through the suppression of IL-17/TNF producing CD4 + T cells., Discussion: Overall, our results reveal a potent inhibitory effect of IL-27 and highlight this cytokine as a promising new therapeutic target in SpA, especially for SpA patients non responders to currently approved biotherapies., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Jouhault, Cherqaoui, Jobart-Malfait, Glatigny, Lauraine, Hulot, Morelle, Hagege, Ermoza, El Marjou, Izac, Saintpierre, Letourneur, Rémy, Anegon, Boissier, Chiocchia, Breban and Araujo.)

Background & Aims: Axin1 is a negative regulator of wingless-type MMTV integration site family, member 1 (Wnt)/β-catenin signaling with tumor-suppressor function. The Wnt pathway has a critical role in the intestine, both during homeostasis and cancer, but the role of Axin1 remains elusive., Methods: We assessed the role of Axin1 in normal intestinal homeostasis, with control, epithelial-specific, Axin1-knockout mice (Axin1 ΔIEC ) and Axin2-knockout mice. We evaluated the tumor-suppressor function of Axin1 during chemically induced colorectal tumorigenesis and dextran sulfate sodium-induced colitis, and performed comparative gene expression profiling by whole-genome RNA sequencing. The clinical relevance of the Axin1-dependent gene expression signature then was tested in a database of 2239 clinical colorectal cancer (CRC) samples., Results: We found that Axin1 was dispensable for normal intestinal homeostasis and redundant with Axin2 for Wnt pathway down-regulation. Axin1 deficiency in intestinal epithelial cells rendered mice more susceptible to chemically induced colon carcinogenesis, but reduced dextran sulfate sodium-induced colitis by attenuating the induction of a proinflammatory program. RNA-seq analyses identified an interferon γ/T-helper1 immune program controlled by Axin1 that enhances the inflammatory response and protects against CRC. The Axin1-dependent gene expression signature was applied to human CRC samples and identified a group of patients with potential vulnerability to immune checkpoint blockade therapies., Conclusions: Our study establishes, in vivo, that Axin1 has redundant function with Axin2 for Wnt down-regulation and infers a new role for Axin1. Physiologically, Axin1 stimulates gut inflammation via an interferon γ/Th1 program that prevents tumor growth. Linked to its T-cell-mediated effect, the colonic Axin1 signature offers therapeutic perspectives for CRC., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Toxoplasma gondii is a cyst-forming apicomplexan parasite of virtually all warm-blooded species, with all true cats (Felidae) as definitive hosts. It is the etiologic agent of toxoplasmosis, a disease causing substantial public health burden worldwide. Few intercontinental clonal lineages represent the large majority of isolates worldwide. Little is known about the evolutionary forces driving the success of these lineages, the timing and the mechanisms of their global dispersal. In this study, we analyse a set of 156 genomes and we provide estimates of T. gondii mutation rate and generation time. We elucidate how the evolution of T. gondii populations is intimately linked to the major events that have punctuated the recent history of cats. We show that a unique haplotype, whose length represents only 0.16% of the whole T. gondii genome, is common to all intercontinental lineages and hybrid populations derived from these lineages. This haplotype has accompanied wildcats (Felis silvestris) during their emergence from the wild to domestic settlements, their dispersal in the Old World, and their expansion in the last five centuries to the Americas. The selection of this haplotype is most parsimoniously explained by its role in sexual reproduction of T. gondii in domestic cats., (© 2022. The Author(s).)

Oligophrenin-1 (OPHN1) is a Rho-GTPase-activating protein (RhoGAP), whose mutations are associated with X-linked intellectual disability (XLID). OPHN1 is enriched at the synapse in both pre- and postsynaptic compartments, where it regulates the RhoA/ROCK/MLC2 signaling pathway, playing a critical role in cytoskeleton remodeling and vesicle recycling. Ophn1 knockout (KO) adult mice display some behavioral deficits in multiple tasks, reminiscent of some symptoms in the human pathology. We also previously reported a reduction in dendritic spine density in the adult hippocampus of KO mice. Yet the nature of the deficits occurring in these mice during postnatal development remains elusive. Here, we show that juvenile KO mice present normal basal synaptic transmission, but altered synaptic plasticity, with a selective impairment in long-term depression, but no change in long-term potentiation. This contrasts with the functional deficits that these mice display at the adult stage, as we found that both basal synaptic transmission and long-term potentiation are reduced at later stages, due to presynaptic alterations. In addition, the number of excitatory synapses in adult is increased, suggesting some unsuccessful compensation. Altogether, these results suggest that OPHN1 function at synapses is differentially affected during maturation of the brain, which provides some therapeutic opportunities for early intervention.

Design: Molecular classification is important for the diagnosis and prognosis of adrenocortical tumors (ACT). Transcriptome profiles separate adrenocortical adenomas 'C2' from carcinomas, and identify two groups of carcinomas 'C1A' and 'C1B', of poor and better prognosis respectively. However, many ACT cannot be profiled because of improper or absent freezing procedures, a mandatory requirement so far. The main aim was to determine transcriptome profiles on formalin-fixed paraffin-embedded (FFPE) samples, using the new 3'-end RNA-sequencing technology. A secondary aim was to demonstrate the ability of this technique to explore large FFPE archives, by focusing on the rare oncocytic ACT variants., Methods: We included 131 ACT: a training cohort from Cochin hospital and an independent validation cohort from Wuerzburg hospital. The 3' transcriptome was generated from FFPE samples using QuantSeq (Lexogen, Vienna, Austria) and NextSeq500 (Illumina, San Diego, CA, USA)., Results: In the training cohort, unsupervised clustering identified three groups: 'C1A' aggressive carcinomas (n = 28, 29%), 'C1B' more indolent carcinomas (n = 28, 29%), and 'C2' adenomas (n = 39, 41%). The prognostic value of FFPE transcriptome was confirmed in the validation cohort (5-year OS: 26% in 'C1A' (n = 26) and 100% in 'C1B' (n = 10), P = 0.003). FFPE transcriptome was an independent prognostic factor in a multivariable model including tumor stage and Ki-67 (OS HR: 7.5, P = 0.01). Oncocytic ACT (n = 19) did not form any specific cluster. Oncocytic carcinomas (n = 6) and oncocytic ACT of uncertain malignant potential (n = 4) were all in 'C1B'., Conclusions: The 3' RNA-sequencing represents a convenient solution for determining ACT molecular class from FFPE samples. This technique should facilitate routine use and large retrospective studies.

Male infertility is responsible for approximately half of all cases of reproductive issues. Spermatogenesis originates in a small pool of spermatogonial stem cells (SSCs), which are of interest for therapy of infertility but remain not well defined in humans. Using multiparametric analysis of the side population (SP) phenotype and the α-6 integrin, THY1, and β-2 microglobulin cell markers, we identified a population of human primitive undifferentiated spermatogonia with the phenotype β-2 microglobulin (β-2M) - SPα-6 + THY1 + , which is highly enriched in stem cells. By analyzing the expression signatures of this SSC-enriched population along with other germinal progenitors, we established an exhaustive transcriptome of human spermatogenesis. Transcriptome profiling of the human β-2M - SPα-6 + THY1 + population and comparison with the profile of mouse undifferentiated spermatogonia provide insights into the molecular networks and key transcriptional regulators regulating human SSCs, including the basic-helix-loop-helix (bHLH) transcriptional repressor HES1, which we show to be implicated in maintenance of SSCs in vitro., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)