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1.
Cell ; 182(5): 1198-1213.e14, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32888493

RESUMO

Most loci identified by GWASs have been found in populations of European ancestry (EUR). In trans-ethnic meta-analyses for 15 hematological traits in 746,667 participants, including 184,535 non-EUR individuals, we identified 5,552 trait-variant associations at p < 5 × 10-9, including 71 novel associations not found in EUR populations. We also identified 28 additional novel variants in ancestry-specific, non-EUR meta-analyses, including an IL7 missense variant in South Asians associated with lymphocyte count in vivo and IL-7 secretion levels in vitro. Fine-mapping prioritized variants annotated as functional and generated 95% credible sets that were 30% smaller when using the trans-ethnic as opposed to the EUR-only results. We explored the clinical significance and predictive value of trans-ethnic variants in multiple populations and compared genetic architecture and the effect of natural selection on these blood phenotypes between populations. Altogether, our results for hematological traits highlight the value of a more global representation of populations in genetic studies.


Assuntos
Povo Asiático/genética , Mutação de Sentido Incorreto/genética , Polimorfismo de Nucleotídeo Único/genética , População Branca/genética , Genética , Estudo de Associação Genômica Ampla/métodos , Células HEK293 , Humanos , Interleucina-7/genética , Fenótipo
2.
Cell ; 183(3): 786-801.e19, 2020 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-33125893

RESUMO

Trained immunity, a functional state of myeloid cells, has been proposed as a compelling immune-oncological target. Its efficient induction requires direct engagement of myeloid progenitors in the bone marrow. For this purpose, we developed a bone marrow-avid nanobiologic platform designed specifically to induce trained immunity. We established the potent anti-tumor capabilities of our lead candidate MTP10-HDL in a B16F10 mouse melanoma model. These anti-tumor effects result from trained immunity-induced myelopoiesis caused by epigenetic rewiring of multipotent progenitors in the bone marrow, which overcomes the immunosuppressive tumor microenvironment. Furthermore, MTP10-HDL nanotherapy potentiates checkpoint inhibition in this melanoma model refractory to anti-PD-1 and anti-CTLA-4 therapy. Finally, we determined MTP10-HDL's favorable biodistribution and safety profile in non-human primates. In conclusion, we show that rationally designed nanobiologics can promote trained immunity and elicit a durable anti-tumor response either as a monotherapy or in combination with checkpoint inhibitor drugs.


Assuntos
Inibidores de Checkpoint Imunológico/uso terapêutico , Imunidade , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/patologia , Nanotecnologia , Acetilmuramil-Alanil-Isoglutamina/metabolismo , Animais , Comportamento Animal , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Proliferação de Células/efeitos dos fármacos , Colesterol/metabolismo , Feminino , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/metabolismo , Inibidores de Checkpoint Imunológico/farmacologia , Imunidade/efeitos dos fármacos , Imunoterapia , Lipoproteínas HDL/metabolismo , Camundongos Endogâmicos C57BL , Primatas , Distribuição Tecidual/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos
3.
Cell ; 178(5): 1205-1221.e17, 2019 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-31442408

RESUMO

A hallmark feature of inflammation is the orchestrated recruitment of neutrophils from the bloodstream into inflamed tissue. Although selectins and integrins mediate recruitment in many tissues, they have a minimal role in the lungs and liver. Exploiting an unbiased in vivo functional screen, we identified a lung and liver homing peptide that functionally abrogates neutrophil recruitment to these organs. Using biochemical, genetic, and confocal intravital imaging approaches, we identified dipeptidase-1 (DPEP1) as the target and established its role as a physical adhesion receptor for neutrophil sequestration independent of its enzymatic activity. Importantly, genetic ablation or functional peptide blocking of DPEP1 significantly reduced neutrophil recruitment to the lungs and liver and provided improved survival in models of endotoxemia. Our data establish DPEP1 as a major adhesion receptor on the lung and liver endothelium and identify a therapeutic target for neutrophil-driven inflammatory diseases of the lungs.


Assuntos
Dipeptidases/metabolismo , Neutrófilos/fisiologia , Complexo Glicoproteico GPIb-IX de Plaquetas/metabolismo , Animais , Cilastatina/farmacologia , Cilastatina/uso terapêutico , Dipeptidases/antagonistas & inibidores , Dipeptidases/genética , Modelos Animais de Doenças , Endotoxemia/mortalidade , Endotoxemia/patologia , Endotoxemia/prevenção & controle , Proteínas Ligadas por GPI/antagonistas & inibidores , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/metabolismo , Humanos , Lipopolissacarídeos/farmacologia , Fígado/efeitos dos fármacos , Fígado/imunologia , Fígado/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Pulmão/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos SCID , Infiltração de Neutrófilos/efeitos dos fármacos , Peptídeos/síntese química , Peptídeos/química , Peptídeos/farmacologia , Taxa de Sobrevida
4.
Immunity ; 54(10): 2372-2384.e7, 2021 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-34496223

RESUMO

Spontaneous control of HIV infection has been repeatedly linked to antiviral CD8+ T cells but is not always permanent. To address mechanisms of durable and aborted control of viremia, we evaluated immunologic and virologic parameters longitudinally among 34 HIV-infected subjects with differential outcomes. Despite sustained recognition of autologous virus, HIV-specific proliferative and cytolytic T cell effector functions became selectively and intrinsically impaired prior to aborted control. Longitudinal transcriptomic profiling of functionally impaired HIV-specific CD8+ T cells revealed altered expression of genes related to activation, cytokine-mediated signaling, and cell cycle regulation, including increased expression of the antiproliferative transcription factor KLF2 but not of genes associated with canonical exhaustion. Lymphoid HIV-specific CD8+ T cells also exhibited poor functionality during aborted control relative to durable control. Our results identify selective functional impairment of HIV-specific CD8+ T cells as prognostic of impending aborted HIV control, with implications for clinical monitoring and immunotherapeutic strategies.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Infecções por HIV/imunologia , Infecções por HIV/virologia , Viremia/imunologia , Viremia/virologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva
5.
Genes Dev ; 2022 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-35902118

RESUMO

The PBRM1 subunit of the PBAF (SWI/SNF) chromatin remodeling complex is mutated in ∼40% of clear cell renal cancers. PBRM1 loss has been implicated in responses to immunotherapy in renal cancer, but the mechanism is unclear. DNA damage-induced inflammatory signaling is an important factor determining immunotherapy response. This response is kept in check by the G2/M checkpoint, which prevents progression through mitosis with unrepaired damage. We found that in the absence of PBRM1, p53-dependent p21 up-regulation is delayed after DNA damage, leading to defective transcriptional repression by the DREAM complex and premature entry into mitosis. Consequently, DNA damage-induced inflammatory signaling pathways are activated by cytosolic DNA. Notably, p53 is infrequently mutated in renal cancer, so PBRM1 mutational status is critical to G2/M checkpoint maintenance. Moreover, we found that the ability of PBRM1 deficiency to predict response to immunotherapy correlates with expression of the cytosolic DNA-sensing pathway in clinical samples. These findings have implications for therapeutic responses in renal cancer.

6.
Nature ; 622(7982): 255-260, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37648866

RESUMO

Neptune-sized planets exhibit a wide range of compositions and densities, depending on factors related to their formation and evolution history, such as the distance from their host stars and atmospheric escape processes. They can vary from relatively low-density planets with thick hydrogen-helium atmospheres1,2 to higher-density planets with a substantial amount of water or a rocky interior with a thinner atmosphere, such as HD 95338 b (ref. 3), TOI-849 b (ref. 4) and TOI-2196 b (ref. 5). The discovery of exoplanets in the hot-Neptune desert6, a region close to the host stars with a deficit of Neptune-sized planets, provides insights into the formation and evolution of planetary systems, including the existence of this region itself. Here we show observations of the transiting planet TOI-1853 b, which has a radius of 3.46 ± 0.08 Earth radii and orbits a dwarf star every 1.24 days. This planet has a mass of 73.2 ± 2.7 Earth masses, almost twice that of any other Neptune-sized planet known so far, and a density of 9.7 ± 0.8 grams per cubic centimetre. These values place TOI-1853 b in the middle of the Neptunian desert and imply that heavy elements dominate its mass. The properties of TOI-1853 b present a puzzle for conventional theories of planetary formation and evolution, and could be the result of several proto-planet collisions or the final state of an initially high-eccentricity planet that migrated closer to its parent star.

7.
Immunity ; 49(3): 464-476.e4, 2018 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-30193847

RESUMO

According to the established model of murine innate lymphoid cell (ILC) development, helper ILCs develop separately from natural killer (NK) cells. However, it is unclear how helper ILCs and NK cells develop in humans. Here we elucidated key steps of NK cell, ILC2, and ILC3 development within human tonsils using ex vivo molecular and functional profiling and lineage differentiation assays. We demonstrated that while tonsillar NK cells, ILC2s, and ILC3s originated from a common CD34-CD117+ ILC precursor pool, final steps of ILC2 development deviated independently and became mutually exclusive from those of NK cells and ILC3s, whose developmental pathways overlapped. Moreover, we identified a CD34-CD117+ ILC precursor population that expressed CD56 and gave rise to NK cells and ILC3s but not to ILC2s. These data support a model of human ILC development distinct from the mouse, whereby human NK cells and ILC3s share a common developmental pathway separate from ILC2s.


Assuntos
Células Matadoras Naturais/imunologia , Linfócitos/imunologia , Tonsila Palatina/imunologia , Animais , Antígenos CD34/metabolismo , Antígeno CD56/metabolismo , Diferenciação Celular , Linhagem da Célula , Células Cultivadas , Perfilação da Expressão Gênica , Humanos , Imunidade Inata , Ativação Linfocitária , Camundongos , Proteínas Proto-Oncogênicas c-kit/metabolismo
8.
Nature ; 600(7890): 675-679, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34887591

RESUMO

Increased blood lipid levels are heritable risk factors of cardiovascular disease with varied prevalence worldwide owing to different dietary patterns and medication use1. Despite advances in prevention and treatment, in particular through reducing low-density lipoprotein cholesterol levels2, heart disease remains the leading cause of death worldwide3. Genome-wideassociation studies (GWAS) of blood lipid levels have led to important biological and clinical insights, as well as new drug targets, for cardiovascular disease. However, most previous GWAS4-23 have been conducted in European ancestry populations and may have missed genetic variants that contribute to lipid-level variation in other ancestry groups. These include differences in allele frequencies, effect sizes and linkage-disequilibrium patterns24. Here we conduct a multi-ancestry, genome-wide genetic discovery meta-analysis of lipid levels in approximately 1.65 million individuals, including 350,000 of non-European ancestries. We quantify the gain in studying non-European ancestries and provide evidence to support the expansion of recruitment of additional ancestries, even with relatively small sample sizes. We find that increasing diversity rather than studying additional individuals of European ancestry results in substantial improvements in fine-mapping functional variants and portability of polygenic prediction (evaluated in approximately 295,000 individuals from 7 ancestry groupings). Modest gains in the number of discovered loci and ancestry-specific variants were also achieved. As GWAS expand emphasis beyond the identification of genes and fundamental biology towards the use of genetic variants for preventive and precision medicine25, we anticipate that increased diversity of participants will lead to more accurate and equitable26 application of polygenic scores in clinical practice.


Assuntos
Doenças Cardiovasculares , Estudo de Associação Genômica Ampla , Doenças Cardiovasculares/genética , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla/métodos , Humanos , Desequilíbrio de Ligação , Herança Multifatorial , Polimorfismo de Nucleotídeo Único/genética , Grupos Populacionais
9.
Mol Cell ; 73(5): 959-970.e5, 2019 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-30686592

RESUMO

Ribosomes undergo substantial conformational changes during translation elongation to accommodate incoming aminoacyl-tRNAs and translocate along the mRNA template. We used multiple elongation inhibitors and chemical probing to define ribosome conformational states corresponding to differently sized ribosome-protected mRNA fragments (RPFs) generated by ribosome profiling. We show, using various genetic and environmental perturbations, that short 20-22 or classical 27-29 nucleotide RPFs correspond to ribosomes with open or occupied ribosomal A sites, respectively. These distinct states of translation elongation are readily discerned by ribosome profiling in all eukaryotes we tested, including fungi, worms, and mammals. This high-resolution ribosome profiling approach reveals mechanisms of translation-elongation arrest during distinct stress conditions. Hyperosmotic stress inhibits translocation through Rck2-dependent eEF2 phosphorylation, whereas oxidative stress traps ribosomes in a pre-translocation state, independent of Rck2-driven eEF2 phosphorylation. These results provide insights and approaches for defining the molecular events that impact translation elongation throughout biology.


Assuntos
Perfilação da Expressão Gênica/métodos , Elongação Traducional da Cadeia Peptídica , Proteínas Ribossômicas/genética , Ribossomos/genética , Estresse Fisiológico , Transcriptoma , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Códon , Células HeLa , Humanos , Conformação de Ácido Nucleico , Pressão Osmótica , Estresse Oxidativo , Fator 2 de Elongação de Peptídeos/genética , Fator 2 de Elongação de Peptídeos/metabolismo , Fosforilação , Conformação Proteica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA de Transferência/química , RNA de Transferência/genética , RNA de Transferência/metabolismo , Proteínas Ribossômicas/química , Proteínas Ribossômicas/metabolismo , Ribossomos/química , Ribossomos/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Relação Estrutura-Atividade , Aminoacilação de RNA de Transferência
10.
Proc Natl Acad Sci U S A ; 121(42): e2406143121, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39374381

RESUMO

Summer temperature extremes can have large impacts on humans and the biosphere, and an increase in heat extremes is one of the most visible symptoms of climate change. Multiple mechanisms have been proposed that would predict faster warming of heat extremes than typical summer days, but it is unclear whether this is occurring. Here, we show that, in both observations and historical climate model simulations, the hottest summer days have warmed at the same pace as the median globally, in each hemisphere, and in the tropics from 1959 to 2023. In contrast, the coldest summer days have warmed more slowly than the median in the global average, a signal that is not simulated in any of 262 simulations across 28 CMIP6 models. The observed stretching of the cold tail indicates that observed summertime temperatures have become more variable despite the lack of hot day amplification. The interannual variability and trend in the warming of both hot and cold extremes compared to the median can be explained from a surface energy balance perspective based on changes in net surface radiation and evaporative fraction. Tropical hot day amplification is projected to emerge in the future (2024-2099, SSP3-7.0 scenario), while Northern Hemisphere heat extremes are expected to continue to follow the median.

11.
Proc Natl Acad Sci U S A ; 121(1): e2302480120, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38147646

RESUMO

Arid and semi-arid regions of the world are particularly vulnerable to greenhouse gas-driven hydroclimate change. Climate models are our primary tool for projecting the future hydroclimate that society in these regions must adapt to, but here, we present a concerning discrepancy between observed and model-based historical hydroclimate trends. Over the arid/semi-arid regions of the world, the predominant signal in all model simulations is an increase in atmospheric water vapor, on average, over the last four decades, in association with the increased water vapor-holding capacity of a warmer atmosphere. In observations, this increase in atmospheric water vapor has not happened, suggesting that the availability of moisture to satisfy the increased atmospheric demand is lower in reality than in models in arid/semi-arid regions. This discrepancy is most clear in locations that are arid/semi-arid year round, but it is also apparent in more humid regions during the most arid months of the year. It indicates a major gap in our understanding and modeling capabilities which could have severe implications for hydroclimate projections, including fire hazard, moving forward.

12.
Proc Natl Acad Sci U S A ; 121(17): e2307216121, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38621126

RESUMO

Uncontrolled fires place considerable burdens on forest ecosystems, compromising our ability to meet conservation and restoration goals. A poor understanding of the impacts of fire on ecosystems and their biodiversity exacerbates this challenge, particularly in tropical regions where few studies have applied consistent analytical techniques to examine a broad range of ecological impacts over multiyear time frames. We compiled 16 y of data on ecosystem properties (17 variables) and biodiversity (21 variables) from a tropical peatland in Indonesia to assess fire impacts and infer the potential for recovery. Burned forest experienced altered structural and microclimatic conditions, resulting in a proliferation of nonforest vegetation and erosion of forest ecosystem properties and biodiversity. Compared to unburned forest, habitat structure, tree density, and canopy cover deteriorated by 58 to 98%, while declines in species diversity and abundance were most pronounced for trees, damselflies, and butterflies, particularly for forest specialist species. Tracking ecosystem property and biodiversity datasets over time revealed most to be sensitive to recurrent high-intensity fires within the wider landscape. These megafires immediately compromised water quality and tree reproductive phenology, crashing commercially valuable fish populations within 3 mo and driving a gradual decline in threatened vertebrates over 9 mo. Burned forest remained structurally compromised long after a burn event, but vegetation showed some signs of recovery over a 12-y period. Our findings demonstrate that, if left uncontrolled, fire may be a pervasive threat to the ecological functioning of tropical forests, underscoring the importance of fire prevention and long-term restoration efforts, as exemplified in Indonesia.


Assuntos
Borboletas , Incêndios , Animais , Ecossistema , Solo , Florestas , Árvores , Biodiversidade
13.
Nature ; 584(7819): E3, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32690940

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

14.
Nature ; 583(7814): 66-71, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32612224

RESUMO

Dental enamel is a principal component of teeth1, and has evolved to bear large chewing forces, resist mechanical fatigue and withstand wear over decades2. Functional impairment and loss of dental enamel, caused by developmental defects or tooth decay (caries), affect health and quality of life, with associated costs to society3. Although the past decade has seen progress in our understanding of enamel formation (amelogenesis) and the functional properties of mature enamel, attempts to repair lesions in this material or to synthesize it in vitro have had limited success4-6. This is partly due to the highly hierarchical structure of enamel and additional complexities arising from chemical gradients7-9. Here we show, using atomic-scale quantitative imaging and correlative spectroscopies, that the nanoscale crystallites of hydroxylapatite (Ca5(PO4)3(OH)), which are the fundamental building blocks of enamel, comprise two nanometric layers enriched in magnesium flanking a core rich in sodium, fluoride and carbonate ions; this sandwich core is surrounded by a shell with lower concentration of substitutional defects. A mechanical model based on density functional theory calculations and X-ray diffraction data predicts that residual stresses arise because of the chemical gradients, in agreement with preferential dissolution of the crystallite core in acidic media. Furthermore, stresses may affect the mechanical resilience of enamel. The two additional layers of hierarchy suggest a possible new model for biological control over crystal growth during amelogenesis, and hint at implications for the preservation of biomarkers during tooth development.


Assuntos
Amelogênese , Esmalte Dentário/química , Ácidos/química , Cálcio/química , Carbonatos/química , Cristalização , Teoria da Densidade Funcional , Esmalte Dentário/ultraestrutura , Durapatita/química , Fluoretos/química , Humanos , Magnésio/química , Microscopia Eletrônica de Transmissão e Varredura , Sódio/química , Tomografia , Difração de Raios X
15.
Nature ; 585(7825): 363-367, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32939071

RESUMO

Astronomers have discovered thousands of planets outside the Solar System1, most of which orbit stars that will eventually evolve into red giants and then into white dwarfs. During the red giant phase, any close-orbiting planets will be engulfed by the star2, but more distant planets can survive this phase and remain in orbit around the white dwarf3,4. Some white dwarfs show evidence for rocky material floating in their atmospheres5, in warm debris disks6-9 or orbiting very closely10-12, which has been interpreted as the debris of rocky planets that were scattered inwards and tidally disrupted13. Recently, the discovery of a gaseous debris disk with a composition similar to that of ice giant planets14 demonstrated that massive planets might also find their way into tight orbits around white dwarfs, but it is unclear whether these planets can survive the journey. So far, no intact planets have been detected in close orbits around white dwarfs. Here we report the observation of a giant planet candidate transiting the white dwarf WD 1856+534 (TIC 267574918) every 1.4 days. We observed and modelled the periodic dimming of the white dwarf caused by the planet candidate passing in front of the star in its orbit. The planet candidate is roughly the same size as Jupiter and is no more than 14 times as massive (with 95 per cent confidence). Other cases of white dwarfs with close brown dwarf or stellar companions are explained as the consequence of common-envelope evolution, wherein the original orbit is enveloped during the red giant phase and shrinks owing to friction. In this case, however, the long orbital period (compared with other white dwarfs with close brown dwarf or stellar companions) and low mass of the planet candidate make common-envelope evolution less likely. Instead, our findings for the WD 1856+534 system indicate that giant planets can be scattered into tight orbits without being tidally disrupted, motivating the search for smaller transiting planets around white dwarfs.

16.
Nature ; 583(7814): 39-42, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32612222

RESUMO

The interiors of giant planets remain poorly understood. Even for the planets in the Solar System, difficulties in observation lead to large uncertainties in the properties of planetary cores. Exoplanets that have undergone rare evolutionary processes provide a route to understanding planetary interiors. Planets found in and near the typically barren hot-Neptune 'desert'1,2 (a region in mass-radius space that contains few planets) have proved to be particularly valuable in this regard. These planets include HD149026b3, which is thought to have an unusually massive core, and recent discoveries such as LTT9779b4 and NGTS-4b5, on which photoevaporation has removed a substantial part of their outer atmospheres. Here we report observations of the planet TOI-849b, which has a radius smaller than Neptune's but an anomalously large mass of [Formula: see text] Earth masses and a density of [Formula: see text] grams per cubic centimetre, similar to Earth's. Interior-structure models suggest that any gaseous envelope of pure hydrogen and helium consists of no more than [Formula: see text] per cent of the total planetary mass. The planet could have been a gas giant before undergoing extreme mass loss via thermal self-disruption or giant planet collisions, or it could have avoided substantial gas accretion, perhaps through gap opening or late formation6. Although photoevaporation rates cannot account for the mass loss required to reduce a Jupiter-like gas giant, they can remove a small (a few Earth masses) hydrogen and helium envelope on timescales of several billion years, implying that any remaining atmosphere on TOI-849b is likely to be enriched by water or other volatiles from the planetary interior. We conclude that TOI-849b is the remnant core of a giant planet.

17.
J Neurosci ; 44(9)2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38242697

RESUMO

Cardiovascular homeostasis is maintained, in part, by neural signals arising from arterial baroreceptors that apprise the brain of blood volume and pressure. Here, we test whether neurons within the nodose ganglia that express angiotensin type-1a receptors (referred to as NGAT1aR) serve as baroreceptors that differentially influence blood pressure (BP) in male and female mice. Using Agtr1a-Cre mice and Cre-dependent AAVs to direct tdTomato to NGAT1aR, neuroanatomical studies revealed that NGAT1aR receive input from the aortic arch, project to the caudal nucleus of the solitary tract (NTS), and synthesize mechanosensitive ion channels, Piezo1/2 To evaluate the functionality of NGAT1aR, we directed the fluorescent calcium indicator (GCaMP6s) or the light-sensitive channelrhodopsin-2 (ChR2) to Agtr1a-containing neurons. Two-photon intravital imaging in Agtr1a-GCaMP6s mice revealed that NGAT1aR couple their firing to elevated BP, induced by phenylephrine (i.v.). Furthermore, optical excitation of NGAT1aR at their soma or axon terminals within the caudal NTS of Agtr1a-ChR2 mice elicited robust frequency-dependent decreases in BP and heart rate, indicating that NGAT1aR are sufficient to elicit appropriate compensatory responses to vascular mechanosensation. Optical excitation also elicited hypotensive and bradycardic responses in ChR2-expressing mice that were subjected to deoxycorticosterone acetate (DOCA)-salt hypertension; however, the duration of these effects was altered, suggestive of hypertension-induced impairment of the baroreflex. Similarly, increased GCaMP6s fluorescence observed after administration of phenylephrine was delayed in mice subjected to DOCA-salt or chronic delivery of angiotensin II. Collectively, these results reveal the structure and function of NGAT1aR and suggest that such neurons may be exploited to discern and relieve hypertension.


Assuntos
Acetato de Desoxicorticosterona , Hipertensão , Proteína Vermelha Fluorescente , Camundongos , Masculino , Feminino , Animais , Acetato de Desoxicorticosterona/farmacologia , Núcleo Solitário/fisiologia , Células Receptoras Sensoriais , Pressão Sanguínea/fisiologia , Fenilefrina/farmacologia , Canais Iônicos
18.
Am J Hum Genet ; 109(8): 1366-1387, 2022 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-35931049

RESUMO

A major challenge of genome-wide association studies (GWASs) is to translate phenotypic associations into biological insights. Here, we integrate a large GWAS on blood lipids involving 1.6 million individuals from five ancestries with a wide array of functional genomic datasets to discover regulatory mechanisms underlying lipid associations. We first prioritize lipid-associated genes with expression quantitative trait locus (eQTL) colocalizations and then add chromatin interaction data to narrow the search for functional genes. Polygenic enrichment analysis across 697 annotations from a host of tissues and cell types confirms the central role of the liver in lipid levels and highlights the selective enrichment of adipose-specific chromatin marks in high-density lipoprotein cholesterol and triglycerides. Overlapping transcription factor (TF) binding sites with lipid-associated loci identifies TFs relevant in lipid biology. In addition, we present an integrative framework to prioritize causal variants at GWAS loci, producing a comprehensive list of candidate causal genes and variants with multiple layers of functional evidence. We highlight two of the prioritized genes, CREBRF and RRBP1, which show convergent evidence across functional datasets supporting their roles in lipid biology.


Assuntos
Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo Único , Cromatina/genética , Genômica , Humanos , Lipídeos/genética , Polimorfismo de Nucleotídeo Único/genética
19.
N Engl J Med ; 386(23): 2188-2200, 2022 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-35443106

RESUMO

BACKGROUND: The monoclonal-antibody combination AZD7442 is composed of tixagevimab and cilgavimab, two neutralizing antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that have an extended half-life and have been shown to have prophylactic and therapeutic effects in animal models. Pharmacokinetic data in humans indicate that AZD7442 has an extended half-life of approximately 90 days. METHODS: In an ongoing phase 3 trial, we enrolled adults (≥18 years of age) who had an increased risk of an inadequate response to vaccination against coronavirus disease 2019 (Covid-19), an increased risk of exposure to SARS-CoV-2, or both. Participants were randomly assigned in a 2:1 ratio to receive a single dose (two consecutive intramuscular injections, one containing tixagevimab and the other containing cilgavimab) of either 300 mg of AZD7442 or saline placebo, and they were followed for up to 183 days in the primary analysis. The primary safety end point was the incidence of adverse events after a single dose of AZD7442. The primary efficacy end point was symptomatic Covid-19 (SARS-CoV-2 infection confirmed by means of reverse-transcriptase-polymerase-chain-reaction assay) occurring after administration of AZD7442 or placebo and on or before day 183. RESULTS: A total of 5197 participants underwent randomization and received one dose of AZD7442 or placebo (3460 in the AZD7442 group and 1737 in the placebo group). The primary analysis was conducted after 30% of the participants had become aware of their randomized assignment. In total, 1221 of 3461 participants (35.3%) in the AZD7442 group and 593 of 1736 participants (34.2%) in the placebo group reported having at least one adverse event, most of which were mild or moderate in severity. Symptomatic Covid-19 occurred in 8 of 3441 participants (0.2%) in the AZD7442 group and in 17 of 1731 participants (1.0%) in the placebo group (relative risk reduction, 76.7%; 95% confidence interval [CI], 46.0 to 90.0; P<0.001); extended follow-up at a median of 6 months showed a relative risk reduction of 82.8% (95% CI, 65.8 to 91.4). Five cases of severe or critical Covid-19 and two Covid-19-related deaths occurred, all in the placebo group. CONCLUSIONS: A single dose of AZD7442 had efficacy for the prevention of Covid-19, without evident safety concerns. (Funded by AstraZeneca and the U.S. government; PROVENT ClinicalTrials.gov number, NCT04625725.).


Assuntos
Antivirais , COVID-19 , Adulto , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/uso terapêutico , Anticorpos Neutralizantes/administração & dosagem , Anticorpos Neutralizantes/uso terapêutico , Antivirais/administração & dosagem , Antivirais/uso terapêutico , COVID-19/prevenção & controle , Método Duplo-Cego , Combinação de Medicamentos , Humanos , Injeções Intramusculares , SARS-CoV-2
20.
J Virol ; 98(3): e0172023, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38412036

RESUMO

The rational design of HIV-1 immunogens to trigger the development of broadly neutralizing antibodies (bNAbs) requires understanding the viral evolutionary pathways influencing this process. An acute HIV-1-infected individual exhibiting >50% plasma neutralization breadth developed neutralizing antibody specificities against the CD4-binding site (CD4bs) and V1V2 regions of Env gp120. Comparison of pseudoviruses derived from early and late autologous env sequences demonstrated the development of >2 log resistance to VRC13 but not to other CD4bs-specific bNAbs. Mapping studies indicated that the V3 and CD4-binding loops of Env gp120 contributed significantly to developing resistance to the autologous neutralizing response and that the CD4-binding loop (CD4BL) specifically was responsible for the developing resistance to VRC13. Tracking viral evolution during the development of this cross-neutralizing CD4bs response identified amino acid substitutions arising at only 4 of 11 known VRC13 contact sites (K282, T283, K421, and V471). However, each of these mutations was external to the V3 and CD4BL regions conferring resistance to VRC13 and was transient in nature. Rather, complete resistance to VRC13 was achieved through the cooperative expression of a cluster of single amino acid changes within and immediately adjacent to the CD4BL, including a T359I substitution, exchange of a potential N-linked glycosylation (PNLG) site to residue S362 from N363, and a P369L substitution. Collectively, our data characterize complex HIV-1 env evolution in an individual developing resistance to a VRC13-like neutralizing antibody response and identify novel VRC13-associated escape mutations that may be important to inducing VRC13-like bNAbs for lineage-based immunogens.IMPORTANCEThe pursuit of eliciting broadly neutralizing antibodies (bNAbs) through vaccination and their use as therapeutics remains a significant focus in the effort to eradicate HIV-1. Key to our understanding of this approach is a more extensive understanding of bNAb contact sites and susceptible escape mutations in HIV-1 envelope (env). We identified a broad neutralizer exhibiting VRC13-like responses, a non-germline restricted class of CD4-binding site antibody distinct from the well-studied VRC01-class. Through longitudinal envelope sequencing and Env-pseudotyped neutralization assays, we characterized a complex escape pathway requiring the cooperative evolution of four amino acid changes to confer complete resistance to VRC13. This suggests that VRC13-class bNAbs may be refractory to rapid escape and attractive for therapeutic applications. Furthermore, the identification of longitudinal viral changes concomitant with the development of neutralization breadth may help identify the viral intermediates needed for the maturation of VRC13-like responses and the design of lineage-based immunogens.


Assuntos
Anticorpos Amplamente Neutralizantes , Infecções por HIV , Humanos , Aminoácidos , Anticorpos Amplamente Neutralizantes/imunologia , Antígenos CD4/genética , Produtos do Gene env do Vírus da Imunodeficiência Humana/genética , Epitopos , Anticorpos Anti-HIV , Antígenos HIV , Proteína gp120 do Envelope de HIV/genética , Soropositividade para HIV , HIV-1/genética , Vacinas contra a AIDS/imunologia
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