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Found 37769 matches. Displaying 781-790
Sokal A, Bastard P, Chappert P, Barba-Spaeth G, Fourati S, Vanderberghe A, Lagouge-Roussey P, Meyts I, Gervais A, Bouvier-Alias M, Azzaoui I, Fernandez I, de la Selle A, Zhang Q, Bizien L, Pellier I, Linglart A, Rothenbuhler A, Marcoux E, Anxionnat R, Cheikh N, Leger J, Amador-Borrero B, Fouyssac F, Menut V, Goffard JC, Storey C, Demily C, Mallebranche C, Troya J, Pujol A, Zins M, Tiberghien P, Gray PE, McNaughton P, Sullivan A, Peake J, Levy R, Languille L, Rodiguez-Gallego C, Boisson B, Gallien S, Neven B, Michel M, Godeau B, Abel L, Rey FA, Weill JC, Reynaud CA, Tangye SG, Casanova JL, Mahevas M
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Human type I IFN deficiency does not impair B cell response to SARS-CoV-2 mRNA vaccination

JOURNAL OF EXPERIMENTAL MEDICINE 2022 NOV 7; 220(1):? Article e20220258
Intact B cell responses to SARS-CoV-2 mRNA vaccines in patients with genetic or acquired type I IFN deficiencies suggest that type I IFNs induced by mRNA vaccines are not required for vaccine efficacy. Inborn and acquired deficits of type I interferon (IFN) immunity predispose to life-threatening COVID-19 pneumonia. We longitudinally profiled the B cell response to mRNA vaccination in SARS-CoV-2 naive patients with inherited TLR7, IRF7, or IFNAR1 deficiency, as well as young patients with autoantibodies neutralizing type I IFNs due to autoimmune polyendocrine syndrome type-1 (APS-1) and older individuals with age-associated autoantibodies to type I IFNs. The receptor-binding domain spike protein (RBD)-specific memory B cell response in all patients was quantitatively and qualitatively similar to healthy donors. Sustained germinal center responses led to accumulation of somatic hypermutations in immunoglobulin heavy chain genes. The amplitude and duration of, and viral neutralization by, RBD-specific IgG serological response were also largely unaffected by TLR7, IRF7, or IFNAR1 deficiencies up to 7 mo after vaccination in all patients. These results suggest that induction of type I IFN is not required for efficient generation of a humoral response against SARS-CoV-2 by mRNA vaccines.
Clamp loaders are pentameric AAA+ assemblies that use ATP to open and close circular DNA sliding clamps around DNA. Clamp loaders show homology in all organisms, from bacteria to human. The eukaryotic PCNA clamp is loaded onto 3 ' primed DNA by the replication factor C (RFC) hetero-pentameric clamp loader. Eukaryotes also have three alternative RFC-like clamp loaders (RLCs) in which the Rfc1 subunit is substituted by another protein. One of these is the yeast Rad24-RFC (Rad17-RFC in human) that loads a 9-1-1 heterotrimer clamp onto a recessed 5 ' end of DNA. Recent structural studies of Rad24-RFC have discovered an unexpected 5 ' DNA binding site on the outside of the clamp loader and reveal how a 5 ' end can be utilized for loading the 9-1-1 clamp onto DNA. In light of these results, new studies reveal that RFC also contains a 5 ' DNA binding site, which functions in gap repair. These studies also reveal many new features of clamp loaders. As reviewed herein, these recent studies together have transformed our view of the clamp loader mechanism.
Sarhan D, Eisinger S, He F, Bergsland M, Pelicano C, Driescher C, Westberg K, Benitez II, Humoud R, Palano G, Li SJ, Carannante V, Muhr J, Onfelt B, Schlisio S, Ravetch JV, Heuchel R, Lohr MJ, Karlsson MCI
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Targeting myeloid suppressive cells revives cytotoxic anti-tumor responses in pancreatic cancer

ISCIENCE 2022 NOV 18; 25(11):? Article 105317
Immunotherapy for cancer that aims to promote T cell anti-tumor activity has changed current clinical practice, where some previously lethal cancers have now become treatable. However, clinical trials with low response rates have been disappointing for pancreatic ductal adenocarcinoma (PDAC). One suggested explanation is the accumulation of dominantly immunosuppressive tumor-associated macrophages and myeloid-derived suppressor cells in the tumor microenvironment (TME). Using retrospectively collected tumor specimens and transcriptomic data from PDAC, we demonstrate that expression of the scavenger receptor MARCO correlates with poor prognosis and a lymphocyte-excluding tumor phenotype. PDAC cell lines produce IL-10 and induce high expression of MARCO in myeloid cells, and this was further enhanced during hypoxic conditions. These myeloid cells suppressed effector T and natural killer (NK) cells and blocked NK cell tumor infiltration and tumor killing in a PDAC 3D-spheroid model. Anti-human MARCO (anti-hMARCO) antibody targeting triggered the repolarization of tumor-associated macrophages and activated the inflammasome machinery, resulting in IL-18 production. This in turn enhanced T cell and NK cell functions. The targeting of MARCO thus remodels the TME and represents a rational approach to make immunotherapy more efficient in PDAC patients.
Shih T, De D, Daveluy SD, Hogeling M, Lowes MA, Sayed C, Shi VY, Hsiao JL
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Real-World Considerations of Candidacy for Biologics in Hidradenitis Suppurativa

AMERICAN JOURNAL OF CLINICAL DERMATOLOGY 2022 NOV; 23(6):749-753 Article s40257-022-00711-1
Hidradenitis suppurativa (HS) is a chronic, progressive inflammatory skin disease that is often recalcitrant to multiple treatments. In determining biologic candidacy for patients with HS, we propose a paradigm shift away from Hurley staging and towards consideration of other variables. Biologics represent a long-term treatment option for HS that may serve as a disease-modifying agent. These medications are typically initiated in patients with moderate to severe disease, which, based on inclusion criteria in clinical trials, is often defined as Hurley stage II or III disease, at which point irreversible tissue damage has already occurred. In real-world clinical settings, these considerations include treatments tried and failed, predicted disease trajectory, disease characteristics beyond lesion type, impact of disease on patients' functional status and quality of life, and patient comorbidities, venturing away from the limitations of Hurley stage designations. Future clinical trials may benefit from inclusion of recalcitrant Hurley stage I patients, which may then re-shape treatment guidelines and insurance coverage and improve patient access to biologic treatments.
Collier AD, Yasmin N, Chang GQ, Karatayev O, Khalizova N, Fam M, Abdulai AR, Yu BY, Leibowitz SF
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Embryonic ethanol exposure induces ectopic Hcrt and MCH neurons outside hypothalamus in rats and zebrafish: Role in ethanol-induced behavioural disturbances

ADDICTION BIOLOGY 2022 NOV; 27(6):? Article e13238
Embryonic exposure to ethanol increases the risk for alcohol use disorder in humans and stimulates alcohol-related behaviours in different animal models. Evidence in rats and zebrafish suggests that this phenomenon induced by ethanol at low-moderate concentrations involves a stimulatory effect on neurogenesis and density of hypothalamic neurons expressing the peptides, hypocretin/orexin (Hcrt) and melanin-concentrating hormone (MCH), known to promote alcohol consumption. Building on our report in zebrafish showing that ethanol induces ectopic expression of Hcrt neurons outside the hypothalamus, we investigated here whether embryonic ethanol exposure also induces ectopic peptide neurons in rats similar to zebrafish and affects their morphological characteristics and if these ectopic neurons are functional and have a role in the ethanol-induced disturbances in behaviour. We demonstrate in rats that ethanol at a low-moderate dose, in addition to increasing Hcrt and MCH neurons in the lateral hypothalamus where they are normally concentrated, induces ectopic expression of these peptide neurons further anterior in the nucleus accumbens core and ventromedial caudate putamen where they have not been previously observed and causes morphological changes relative to normally located hypothalamic neurons. Similar to rats, embryonic ethanol exposure at a low-moderate dose in zebrafish induces ectopic Hcrt neurons anterior to the hypothalamus and alters their morphology. Notably, laser ablation of these ectopic Hcrt neurons blocks the behavioural effects induced by ethanol exposure, including increased anxiety and locomotor activity. These findings suggest that the ectopic peptide neurons are functional and contribute to the ethanol-induced behavioural disturbances related to the overconsumption of alcohol.
Toh H, Yang CT, Formenti G, Raja K, Yan L, Tracey A, Chow W, Howe K, Bergeron LA, Zhang GJ, Haase B, Mountcastle J, Fedrigo O, Fogg J, Kirilenko B, Munegowda C, Hiller M, Jain A, Kihara D, Rhie A, Phillippy AM, Swanson SA, Jiang P, Clegg DO, Jarvis ED, Thomson JA, Stewart R, Chaisson MJP, Bukhman YV
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A haplotype-resolved genome assembly of the Nile rat facilitates exploration of the genetic basis of diabetes

BMC BIOLOGY 2022 NOV 8; 20(1):? Article 245
Background The Nile rat (Avicanthis niloticus) is an important animal model because of its robust diurnal rhythm, a cone-rich retina, and a propensity to develop diet-induced diabetes without chemical or genetic modifications. A closer similarity to humans in these aspects, compared to the widely used Mus musculus and Rattus norvegicus models, holds the promise of better translation of research findings to the clinic. Results We report a 2.5 Gb, chromosome-level reference genome assembly with fully resolved parental haplotypes, generated with the Vertebrate Genomes Project (VGP). The assembly is highly contiguous, with contig N50 of 11.1 Mb, scaffold N50 of 83 Mb, and 95.2% of the sequence assigned to chromosomes. We used a novel workflow to identify 3613 segmental duplications and quantify duplicated genes. Comparative analyses revealed unique genomic features of the Nile rat, including some that affect genes associated with type 2 diabetes and metabolic dysfunctions. We discuss 14 genes that are heterozygous in the Nile rat or highly diverged from the house mouse. Conclusions Our findings reflect the exceptional level of genomic resolution present in this assembly, which will greatly expand the potential of the Nile rat as a model organism.
Nguyenla X, Wehri E, Van Dis E, Biering SB, Yamashiro LH, Zhu C, Stroumza J, Dugast-Darzacq C, Graham TGW, Wang XT, Jockusch S, Tao CAJ, Chien MC, Xie W, Patel DJ, Meyer C, Garzia A, Tuschl T, Russo JJ, Ju JY, Naar AM, Stanley S, Schaletzky J
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Discovery of SARS-CoV-2 antiviral synergy between remdesivir and approved drugs in human lung cells

SCIENTIFIC REPORTS 2022 NOV 2; 12(1):? Article 18506
SARS coronavirus 2 (SARS-CoV-2) has caused an ongoing global pandemic with significant mortality and morbidity. At this time, the only FDA-approved therapeutic for COVID-19 is remdesivir, a broad-spectrum antiviral nucleoside analog. Efficacy is only moderate, and improved treatment strategies are urgently needed. To accomplish this goal, we devised a strategy to identify compounds that act synergistically with remdesivir in preventing SARS-CoV-2 replication. We conducted combinatorial high-throughput screening in the presence of submaximal remdesivir concentrations, using a human lung epithelial cell line infected with a clinical isolate of SARS-CoV-2. This identified 20 approved drugs that act synergistically with remdesivir, many with favorable pharmacokinetic and safety profiles. Strongest effects were observed with established antivirals, Hepatitis C virus nonstructural protein 5A (HCV NS5A) inhibitors velpatasvir and elbasvir. Combination with their partner drugs sofosbuvir and grazoprevir further increased efficacy, increasing remdesivir's apparent potency > 25-fold. We report that HCV NS5A inhibitors act on the SARS-CoV-2 exonuclease proofreader, providing a possible explanation for the synergy observed with nucleoside analog remdesivir. FDA-approved Hepatitis C therapeutics Epclusa (R) (velpatasvir/sofosbuvir) and Zepatier (R) (elbasvir/grazoprevir) could be further optimized to achieve potency and pharmacokinetic properties that support clinical evaluation in combination with remdesivir.
Nam AS, Dusaj N, Izzo F, Murali R, Myers RM, Mouhieddine TH, Sotelo J, Benbarche S, Waarts M, Gaiti F, Tahris S, Levine R, Abdel-Wahab O, Godley LA, Chaligne R, Ghobrial I, Landau DA
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Single-cell multi-omics of human clonal hematopoiesis reveals that DNMT3A R882 mutations perturb early progenitor states through selective hypomethylation

NATURE GENETICS 2022 OCT; 54(10):1514-+
Somatic mutations in cancer genes have been detected in clonal expansions across healthy human tissue, including in clonal hematopoiesis. However, because mutated and wild-type cells are admixed, we have limited ability to link genotypes with phenotypes. To overcome this limitation, we leveraged multi-modality single-cell sequencing, capturing genotype, transcriptomes and methylomes in progenitors from individuals with DNMT3A R882 mutated clonal hematopoiesis. DNMT3A mutations result in myeloid over lymphoid bias, and an expansion of immature myeloid progenitors primed toward megakaryocytic-erythroid fate, with dysregulated expression of lineage and leukemia stem cell markers. Mutated DNMT3A leads to preferential hypomethylation of polycomb repressive complex 2 targets and a specific CpG flanking motif. Notably, the hypomethylation motif is enriched in binding motifs of key hematopoietic transcription factors, serving as a potential mechanistic link between DNMT3A mutations and aberrant transcriptional phenotypes. Thus, single-cell multi-omics paves the road to defining the downstream consequences of mutations that drive clonal mosaicism. Multi-modality single-cell sequencing determines genotype, transcriptome and methylome information in cells from individuals with DNMT3A R882 mutated clonal hematopoiesis, allowing for the comparison of mutant and wild-type cells from the same individuals.
Palillo JA, Mollenkopf D, Marsh AE, Wittum TE, James JPB, Reichley SR, Ghosh S, Palillo MB, Malbrue R
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Detection of Zoonotic Bacteria and Paragonimus kellicotti in Red Swamp Crayfish (Procambarus clarkii) and the Assessment of Traditional Crayfish Boils

JOURNAL OF FOOD PROTECTION 2022 OCT; 85(10):1388-1396
Studies of red swamp crayfish (Procambarus clarkii) outside of the United States confirm the presence of a variety of zoonotic pathogens, but it is unknown whether these same pathogens occur in P. clarkii in the United States. The U.S. commercial crayfish industry generates $200 million yearly, underscoring the need to evaluate this consumer commodity. The study objectives were to evaluate specific zoonotic pathogens present on P. clarkii from Alabama and Louisiana, states in the southeastern United States, and to determine the effectiveness of traditional food preparation methods to reduce pathogens. Experiment A evaluated the presence of Escherichia coli, Salmonella, Staphylococcus aureus, and Vibrio spp. in crayfish and environmental samples over a 2-month collection period (May to June 2021). Crayfish sampling consisted of swabbing the cephalothorax region; 15 samples were tested for E. coli, Salmonella, and S. aureus, and an additional 15 samples for Vibrio spp. Additionally, crayfish shipping materials were sampled. In experiment B, 92 crayfish were evaluated for Paragonimus kellicotti. Experiment C compared live and boiled crayfish for the presence of Vibrio spp. In experiments A and B, all 60 (100%) crayfish samples and 13 (81.25%) of 16 environmental samples showed growth characteristic of Vibrio spp. Three (5%) of 60 samples showed E. coli growth, with no statistical difference (P = 0.5536) between farms. P. kellicotti, Salmonella, and S. aureus were not recovered from any samples. In experiment C, all 10 (100%) of the live preboiled crayfish samples showed characteristic growth, whereas 1 (10%) of 10 samples of crayfish boiled in unseasoned water showed Vibrio growth (P , 0.0001). These results confirm that Vibrio spp. and E. coli may be present on U.S. commercial crayfish and that care should be taken when handling any materials that come into contact with live crayfish because they can potentially be contaminated.
Kolbe L, Fins JJ
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Health Equity, History, and a New Presidential Bioethics Commission: Lessons from the "Lost" Reports

JOURNAL OF GENERAL INTERNAL MEDICINE 2022 OCT; 37(13):3471-3474
Convening a national bioethics commission has historically been one of the most powerful bioethical legacies a US presidential administration can undertake. The Biden Administration has not yet created such a commission; here we argue that centering health equity and healthcare access would provide a vital framework for a new commission's legacy. Moreover, we demonstrate two crucial historical episodes when American presidents appointed commissions to examine the practical and ethical implications of these very issues. We turn first to the 1952 President's Commission report on "Building America's Health," a lofty vision of universal healthcare access stymied by both political conflict and unaddressed problems of racism in the era's legislation. Its rich yet incomplete account of American health inequities serves as a valuable forerunner to questions of justice in bioethics. We then explore the President's Commission's 1983 report "Securing Access to Healthcare: A Report on the Ethical Implications of Differences in the Availability of Health Services." This report took up the mantle of equity in healthcare access, again with mixed results. Only by understanding the checkered history of these overlooked, practically "lost" reports can a new era in American bioethics successfully re-center the goal of equitable health for all.