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1.
Annu Rev Immunol ; 39: 719-757, 2021 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-33646859

RESUMO

The enigmatic eosinophil has emerged as an exciting component of the immune system, involved in a plethora of homeostatic and inflammatory responses. Substantial progress has been achieved through experimental systems manipulating eosinophils in vivo, initially in mice and more recently in humans. Researchers using eosinophil knockout mice have identified a contributory role for eosinophils in basal and inflammatory processes and protective immunity. Primarily fueled by the purported proinflammatory role of eosinophils in eosinophil-associated diseases, a series of anti-eosinophil therapeutics have emerged as a new class of drugs. These agents, which dramatically deplete eosinophils, provide a valuable opportunity to characterize the consequences of eosinophil knockout humans. Herein, we comparatively describe mouse and human eosinophil knockouts. We put forth the view that human eosinophils negatively contribute to a variety of diseases and, unlike mouse eosinophils, do not yet have an identified role in physiological health; thus, clarifying all roles of eosinophils remains an ongoing pursuit.


Assuntos
Eosinófilos , Preparações Farmacêuticas , Animais , Terapia Biológica , Humanos , Camundongos , Camundongos Knockout
2.
Nat Immunol ; 20(5): 613-625, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30778243

RESUMO

Influenza A, B and C viruses (IAV, IBV and ICV, respectively) circulate globally and infect humans, with IAV and IBV causing the most severe disease. CD8+ T cells confer cross-protection against IAV strains, however the responses of CD8+ T cells to IBV and ICV are understudied. We investigated the breadth of CD8+ T cell cross-recognition and provide evidence of CD8+ T cell cross-reactivity across IAV, IBV and ICV. We identified immunodominant CD8+ T cell epitopes from IBVs that were protective in mice and found memory CD8+ T cells directed against universal and influenza-virus-type-specific epitopes in the blood and lungs of healthy humans. Lung-derived CD8+ T cells displayed tissue-resident memory phenotypes. Notably, CD38+Ki67+CD8+ effector T cells directed against novel epitopes were readily detected in IAV- or IBV-infected pediatric and adult subjects. Our study introduces a new paradigm whereby CD8+ T cells confer unprecedented cross-reactivity across all influenza viruses, a key finding for the design of universal vaccines.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Reações Cruzadas/imunologia , Gammainfluenzavirus/imunologia , Vírus da Influenza A/imunologia , Vírus da Influenza B/imunologia , Influenza Humana/imunologia , Adolescente , Adulto , Idoso , Animais , Linfócitos T CD8-Positivos/virologia , Criança , Epitopos de Linfócito T/imunologia , Feminino , Humanos , Vírus da Influenza A/fisiologia , Vírus da Influenza B/fisiologia , Vacinas contra Influenza/imunologia , Influenza Humana/virologia , Gammainfluenzavirus/fisiologia , Masculino , Camundongos , Pessoa de Meia-Idade , Adulto Jovem
3.
Nat Immunol ; 18(7): 762-770, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28504698

RESUMO

Trafficking of tissue dendritic cells (DCs) via lymph is critical for the generation of cellular immune responses in draining lymph nodes (LNs). In the current study we found that DCs docked to the basolateral surface of lymphatic vessels and transited to the lumen through hyaluronan-mediated interactions with the lymph-specific endothelial receptor LYVE-1, in dynamic transmigratory-cup-like structures. Furthermore, we show that targeted deletion of the gene Lyve1, antibody blockade or depletion of the DC hyaluronan coat not only delayed lymphatic trafficking of dermal DCs but also blunted their capacity to prime CD8+ T cell responses in skin-draining LNs. Our findings uncovered a previously unknown function for LYVE-1 and show that transit through the lymphatic network is initiated by the recognition of leukocyte-derived hyaluronan.


Assuntos
Células Dendríticas/imunologia , Células Endoteliais/metabolismo , Glicoproteínas/genética , Ácido Hialurônico/metabolismo , Vasos Linfáticos/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Animais , Movimento Celular/imunologia , Células Dendríticas/metabolismo , Endotélio Linfático/citologia , Endotélio Linfático/metabolismo , Citometria de Fluxo , Glicoproteínas/metabolismo , Humanos , Imunidade Celular/imunologia , Linfonodos/imunologia , Proteínas de Membrana Transportadoras , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Linfócitos T/imunologia
4.
Nature ; 617(7962): 785-791, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37165193

RESUMO

Different plant species within the grasses were parallel targets of domestication, giving rise to crops with distinct evolutionary histories and traits1. Key traits that distinguish these species are mediated by specialized cell types2. Here we compare the transcriptomes of root cells in three grass species-Zea mays, Sorghum bicolor and Setaria viridis. We show that single-cell and single-nucleus RNA sequencing provide complementary readouts of cell identity in dicots and monocots, warranting a combined analysis. Cell types were mapped across species to identify robust, orthologous marker genes. The comparative cellular analysis shows that the transcriptomes of some cell types diverged more rapidly than those of others-driven, in part, by recruitment of gene modules from other cell types. The data also show that a recent whole-genome duplication provides a rich source of new, highly localized gene expression domains that favour fast-evolving cell types. Together, the cell-by-cell comparative analysis shows how fine-scale cellular profiling can extract conserved modules from a pan transcriptome and provide insight on the evolution of cells that mediate key functions in crops.


Assuntos
Produtos Agrícolas , Setaria (Planta) , Sorghum , Transcriptoma , Zea mays , Sequência de Bases , Regulação da Expressão Gênica de Plantas/genética , Sorghum/citologia , Sorghum/genética , Transcriptoma/genética , Zea mays/citologia , Zea mays/genética , Setaria (Planta)/citologia , Setaria (Planta)/genética , Raízes de Plantas/citologia , Análise da Expressão Gênica de Célula Única , Análise de Sequência de RNA , Produtos Agrícolas/citologia , Produtos Agrícolas/genética , Evolução Molecular
5.
N Engl J Med ; 390(10): 911-921, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38393328

RESUMO

BACKGROUND: Eosinophilic granulomatosis with polyangiitis (EGPA) is a vasculitis characterized by eosinophilic inflammation. Benralizumab, a monoclonal antibody against the interleukin-5α receptor expressed on eosinophils, may be an option for treating EGPA. METHODS: We conducted a multicenter, double-blind, phase 3, randomized, active-controlled noninferiority trial to evaluate the efficacy and safety of benralizumab as compared with mepolizumab. Adults with relapsing or refractory EGPA who were receiving standard care were randomly assigned in a 1:1 ratio to receive benralizumab (30 mg) or mepolizumab (300 mg) subcutaneously every 4 weeks for 52 weeks. The primary end point was remission at weeks 36 and 48 (prespecified noninferiority margin, -25 percentage points). Secondary end points included the accrued duration of remission, time to first relapse, oral glucocorticoid use, eosinophil count, and safety. RESULTS: A total of 140 patients underwent randomization (70 assigned to each group). The adjusted percentage of patients with remission at weeks 36 and 48 was 59% in the benralizumab group and 56% in the mepolizumab group (difference, 3 percentage points; 95% confidence interval [CI], -13 to 18; P = 0.73 for superiority), showing noninferiority but not superiority of benralizumab to mepolizumab. The accrued duration of remission and the time to first relapse were similar in the two groups. Complete withdrawal of oral glucocorticoids during weeks 48 through 52 was achieved in 41% of the patients who received benralizumab and 26% of those who received mepolizumab. The mean (±SD) blood eosinophil count at baseline was 306.0±225.0 per microliter in the benralizumab group and 384.9±563.6 per microliter in the mepolizumab group, decreasing to 32.4±40.8 and 71.8±54.4 per microliter, respectively, at week 52. Adverse events were reported in 90% of the patients in the benralizumab group and 96% of those in the mepolizumab group; serious adverse events were reported in 6% and 13%, respectively. CONCLUSIONS: Benralizumab was noninferior to mepolizumab for the induction of remission in patients with relapsing or refractory EGPA. (Funded by AstraZeneca; MANDARA ClinicalTrials.gov number, NCT04157348.).


Assuntos
Anti-Inflamatórios , Anticorpos Monoclonais Humanizados , Síndrome de Churg-Strauss , Subunidade alfa de Receptor de Interleucina-5 , Adulto , Humanos , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos Monoclonais Humanizados/uso terapêutico , Doença Crônica , Síndrome de Churg-Strauss/tratamento farmacológico , Síndrome de Churg-Strauss/imunologia , Glucocorticoides/efeitos adversos , Glucocorticoides/uso terapêutico , Granulomatose com Poliangiite/tratamento farmacológico , Granulomatose com Poliangiite/imunologia , Recidiva , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/efeitos adversos , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Método Duplo-Cego , Indução de Remissão , Injeções Subcutâneas , Subunidade alfa de Receptor de Interleucina-5/antagonistas & inibidores , Eosinófilos/efeitos dos fármacos , Eosinófilos/imunologia
6.
Immunity ; 49(2): 326-341.e7, 2018 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-30054204

RESUMO

The maintenance of appropriate arterial tone is critically important for normal physiological arterial function. However, the cellular and molecular mechanisms remain poorly defined. Here, we have shown that in the mouse aorta, resident macrophages prevented arterial stiffness and collagen deposition in the steady state. Using phenotyping, transcriptional profiling, and targeted deletion of Csf1r, we have demonstrated that these macrophages-which are a feature of blood vessels invested with smooth muscle cells (SMCs) in both mouse and human tissues-expressed the hyaluronan (HA) receptor LYVE-l. Furthermore, we have shown they possessed the unique ability to modulate collagen expression in SMCs by matrix metalloproteinase MMP-9-dependent proteolysis through engagement of LYVE-1 with the HA pericellular matrix of SMCs. Our study has unveiled a hitherto unknown homeostatic contribution of arterial LYVE-1+ macrophages through the control of collagen production by SMCs and has identified a function of LYVE-1 in leukocytes.


Assuntos
Colágeno/metabolismo , Glicoproteínas/metabolismo , Receptores de Hialuronatos/metabolismo , Macrófagos/metabolismo , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/metabolismo , Rigidez Vascular/fisiologia , Animais , Aorta/fisiologia , Feminino , Glicoproteínas/genética , Humanos , Ácido Hialurônico/metabolismo , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Proteínas de Membrana Transportadoras , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/genética
7.
Nature ; 600(7889): 506-511, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34649268

RESUMO

The evolution of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus leads to new variants that warrant timely epidemiological characterization. Here we use the dense genomic surveillance data generated by the COVID-19 Genomics UK Consortium to reconstruct the dynamics of 71 different lineages in each of 315 English local authorities between September 2020 and June 2021. This analysis reveals a series of subepidemics that peaked in early autumn 2020, followed by a jump in transmissibility of the B.1.1.7/Alpha lineage. The Alpha variant grew when other lineages declined during the second national lockdown and regionally tiered restrictions between November and December 2020. A third more stringent national lockdown suppressed the Alpha variant and eliminated nearly all other lineages in early 2021. Yet a series of variants (most of which contained the spike E484K mutation) defied these trends and persisted at moderately increasing proportions. However, by accounting for sustained introductions, we found that the transmissibility of these variants is unlikely to have exceeded the transmissibility of the Alpha variant. Finally, B.1.617.2/Delta was repeatedly introduced in England and grew rapidly in early summer 2021, constituting approximately 98% of sampled SARS-CoV-2 genomes on 26 June 2021.


Assuntos
COVID-19/epidemiologia , COVID-19/virologia , Genoma Viral/genética , Genômica , SARS-CoV-2/genética , Substituição de Aminoácidos , COVID-19/transmissão , Inglaterra/epidemiologia , Monitoramento Epidemiológico , Humanos , Epidemiologia Molecular , Mutação , Quarentena/estatística & dados numéricos , SARS-CoV-2/classificação , Análise Espaço-Temporal , Glicoproteína da Espícula de Coronavírus/genética
8.
Nature ; 593(7858): 266-269, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33767447

RESUMO

The SARS-CoV-2 lineage B.1.1.7, designated variant of concern (VOC) 202012/01 by Public Health England1, was first identified in the UK in late summer to early autumn 20202. Whole-genome SARS-CoV-2 sequence data collected from community-based diagnostic testing for COVID-19 show an extremely rapid expansion of the B.1.1.7 lineage during autumn 2020, suggesting that it has a selective advantage. Here we show that changes in VOC frequency inferred from genetic data correspond closely to changes inferred by S gene target failures (SGTF) in community-based diagnostic PCR testing. Analysis of trends in SGTF and non-SGTF case numbers in local areas across England shows that B.1.1.7 has higher transmissibility than non-VOC lineages, even if it has a different latent period or generation time. The SGTF data indicate a transient shift in the age composition of reported cases, with cases of B.1.1.7 including a larger share of under 20-year-olds than non-VOC cases. We estimated time-varying reproduction numbers for B.1.1.7 and co-circulating lineages using SGTF and genomic data. The best-supported models did not indicate a substantial difference in VOC transmissibility among different age groups, but all analyses agreed that B.1.1.7 has a substantial transmission advantage over other lineages, with a 50% to 100% higher reproduction number.


Assuntos
COVID-19/transmissão , COVID-19/virologia , Filogenia , SARS-CoV-2/classificação , SARS-CoV-2/patogenicidade , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Número Básico de Reprodução , COVID-19/diagnóstico , COVID-19/epidemiologia , Criança , Pré-Escolar , Inglaterra/epidemiologia , Evolução Molecular , Genoma Viral/genética , Humanos , Lactente , Recém-Nascido , Pessoa de Meia-Idade , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação , Glicoproteína da Espícula de Coronavírus/análise , Glicoproteína da Espícula de Coronavírus/genética , Fatores de Tempo , Adulto Jovem
9.
Plant J ; 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38804053

RESUMO

Ear length (EL) is a key trait that greatly contributes to yield in maize. Although dozens of EL quantitative trait loci have been mapped, very few causal genes have been cloned, and the molecular mechanisms remain largely unknown. Our previous study showed that YIGE1 is involved in sugar and auxin pathways to regulate ear inflorescence meristem (IM) development and thus affects EL in maize. Here, we reveal that YIGE2, the paralog of YIGE1, regulates maize ear development and EL through auxin pathway. Knockout of YIGE2 causes a significant decrease of auxin level, IM length, floret number, EL, and grain yield. yige1 yige2 double mutants had even shorter IM and ears implying that these two genes redundantly regulate IM development and EL. The genes controlling auxin levels are differential expressed in yige1 yige2 double mutants, leading to lower auxin level. These results elucidated the critical role of YIGE2 and the redundancy between YIGE2 and YIGE1 in maize ear development, providing a new genetic resource for maize yield improvement.

10.
Plant J ; 118(2): 457-468, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38198228

RESUMO

Carotenoids perform a broad range of important functions in humans; therefore, carotenoid biofortification of maize (Zea mays L.), one of the most highly produced cereal crops worldwide, would have a global impact on human health. PLASTID TERMINAL OXIDASE (PTOX) genes play an important role in carotenoid metabolism; however, the possible function of PTOX in carotenoid biosynthesis in maize has not yet been explored. In this study, we characterized the maize PTOX locus by forward- and reverse-genetic analyses. While most higher plant species possess a single copy of the PTOX gene, maize carries two tandemly duplicated copies. Characterization of mutants revealed that disruption of either copy resulted in a carotenoid-deficient phenotype. We identified mutations in the PTOX genes as being causal of the classic maize mutant, albescent1. Remarkably, overexpression of ZmPTOX1 significantly improved the content of carotenoids, especially ß-carotene (provitamin A), which was increased by ~threefold, in maize kernels. Overall, our study shows that maize PTOX locus plays an important role in carotenoid biosynthesis in maize kernels and suggests that fine-tuning the expression of this gene could improve the nutritional value of cereal grains.


Assuntos
Oxirredutases , Zea mays , Humanos , Oxirredutases/genética , Oxirredutases/metabolismo , Zea mays/genética , Zea mays/metabolismo , Carotenoides/metabolismo , beta Caroteno/metabolismo , Grão Comestível/genética , Grão Comestível/metabolismo , Plastídeos/genética , Plastídeos/metabolismo
11.
Lancet ; 403(10423): 271-281, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38071986

RESUMO

BACKGROUND: Stepwise intensification of inhaled corticosteroids (ICS) is routine for severe eosinophilic asthma, despite some poor responses to high-dose ICS. Dose reductions are recommended in patients responding to biologics, but little supporting safety evidence exists. METHODS: SHAMAL was a phase 4, randomised, open-label, active-controlled study done at 22 study sites in four countries. Eligible participants were adults (aged ≥18 years) with severe eosinophilic asthma and a five-item Asthma Control Questionnaire score below 1·5 and who received at least three consecutive doses of benralizumab before screening. We randomly assigned patients (3:1) to taper their high-dose ICS to a medium-dose, low-dose, and as-needed dose (reduction group) or continue (reference group) their ICS-formoterol therapy for 32 weeks, followed by a 16-week maintenance period. The primary endpoint was the proportion of patients reducing their ICS-formoterol dose by week 32. The primary outcome was assessed in the reduction group, and safety analyses included all randomly assigned patients receiving study treatment. This study is registered at ClinicalTrials.gov, NCT04159519. FINDINGS: Between Nov 12, 2019, and Feb 16, 2023, we screened and enrolled in the run-in period 208 patients. We randomly assigned 168 (81%) to the reduction (n=125 [74%]) and reference arms (n=43 [26%]). Overall, 110 (92%) patients reduced their ICS-formoterol dose: 18 (15%) to medium-dose, 20 (17%) to low-dose, and 72 (61%) to as-needed only. In 113 (96%) patients, reductions were maintained to week 48; 114 (91%) of patients in the reduction group had zero exacerbations during tapering. Rates of adverse events were similar between groups. 91 (73%) patients had adverse events in the reduction group and 35 (83%) in the reference group. 17 patients had serious adverse events in the study: 12 (10%) in the reduction group and five (12%) in the reference group. No deaths occurred during the study. INTERPRETATION: These findings show that patients controlled on benralizumab can have meaningful reductions in ICS therapy while maintaining asthma control. FUNDING: AstraZeneca.


Assuntos
Antiasmáticos , Anticorpos Monoclonais Humanizados , Asma , Eosinofilia Pulmonar , Adulto , Humanos , Corticosteroides/uso terapêutico , Asma/tratamento farmacológico , Fumarato de Formoterol/uso terapêutico , Eosinofilia Pulmonar/induzido quimicamente
12.
Nature ; 568(7753): 511-516, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30971826

RESUMO

Functional genomics approaches can overcome limitations-such as the lack of identification of robust targets and poor clinical efficacy-that hamper cancer drug development. Here we performed genome-scale CRISPR-Cas9 screens in 324 human cancer cell lines from 30 cancer types and developed a data-driven framework to prioritize candidates for cancer therapeutics. We integrated cell fitness effects with genomic biomarkers and target tractability for drug development to systematically prioritize new targets in defined tissues and genotypes. We verified one of our most promising dependencies, the Werner syndrome ATP-dependent helicase, as a synthetic lethal target in tumours from multiple cancer types with microsatellite instability. Our analysis provides a resource of cancer dependencies, generates a framework to prioritize cancer drug targets and suggests specific new targets. The principles described in this study can inform the initial stages of drug development by contributing to a new, diverse and more effective portfolio of cancer drug targets.


Assuntos
Sistemas CRISPR-Cas/genética , Descoberta de Drogas/métodos , Edição de Genes , Terapia de Alvo Molecular/métodos , Neoplasias/genética , Neoplasias/terapia , Animais , Biomarcadores Tumorais/genética , Linhagem Celular Tumoral , Feminino , Genoma Humano/genética , Humanos , Camundongos , Instabilidade de Microssatélites , Transplante de Neoplasias , Neoplasias/classificação , Neoplasias/patologia , Especificidade de Órgãos , Reprodutibilidade dos Testes , Mutações Sintéticas Letais/genética , Síndrome de Werner/genética , Helicase da Síndrome de Werner/genética
13.
Artigo em Inglês | MEDLINE | ID: mdl-38635834

RESUMO

BACKGROUND: The anti-IgE monoclonal, omalizumab, is widely used for severe asthma. This study aimed to identify biomarkers that predict clinical improvement during one year of omalizumab treatment. METHODS: 1-year, open-label, Study of Mechanisms of action of Omalizumab in Severe Asthma (SoMOSA) involving 216 severe (GINA step 4/5) uncontrolled atopic asthmatics (≥2 severe exacerbations in previous year) on high-dose inhaled corticosteroids, long-acting ß-agonists, ± mOCS. It had two phases: 0-16 weeks, to assess early clinical improvement by Global Evaluation of Therapeutic Effectiveness (GETE), and 16-52 weeks, to assess late responses by ≥50% reduction in exacerbations or dose of maintenance oral corticosteroids (mOCS). All participants provided samples (exhaled breath, blood, sputum, urine) before and after 16 weeks of omalizumab treatment. RESULTS: 191 patients completed phase 1; 63% had early improvement. Of 173 who completed phase 2, 69% had reduced exacerbations by ≥50%, while 57% (37/65) on mOCS reduced their dose by ≥50%. The primary outcome 2, 3-dinor-11-ß-PGF2α, GETE and standard clinical biomarkers (blood and sputum eosinophils, exhaled nitric oxide, serum IgE) did not predict either clinical response. Five breathomics (GC-MS) and 5 plasma lipid biomarkers strongly predicted the ≥50% reduction in exacerbations (receiver operating characteristic area under the curve (AUC): 0.780 and 0.922, respectively) and early responses (AUC:0.835 and 0.949, respectively). In independent cohorts, the GC-MS biomarkers differentiated between severe and mild asthma. Conclusions This is the first discovery of omics biomarkers that predict improvement to a biologic for asthma. Their prospective validation and development for clinical use is justified. This article is open access and distributed under the terms of the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/).

14.
Proc Natl Acad Sci U S A ; 119(2)2022 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-34996873

RESUMO

Carpels in maize undergo programmed cell death in half of the flowers initiated in ears and in all flowers in tassels. The HD-ZIP I transcription factor gene GRASSY TILLERS1 (GT1) is one of only a few genes known to regulate this process. To identify additional regulators of carpel suppression, we performed a gt1 enhancer screen and found a genetic interaction between gt1 and ramosa3 (ra3). RA3 is a classic inflorescence meristem determinacy gene that encodes a trehalose-6-phosphate (T6P) phosphatase (TPP). Dissection of floral development revealed that ra3 single mutants have partially derepressed carpels, whereas gt1;ra3 double mutants have completely derepressed carpels. Surprisingly, gt1 suppresses ra3 inflorescence branching, revealing a role for gt1 in meristem determinacy. Supporting these genetic interactions, GT1 and RA3 proteins colocalize to carpel nuclei in developing flowers. Global expression profiling revealed common genes misregulated in single and double mutant flowers, as well as in derepressed gt1 axillary meristems. Indeed, we found that ra3 enhances gt1 vegetative branching, similar to the roles for the trehalose pathway and GT1 homologs in the eudicots. This functional conservation over ∼160 million years of evolution reveals ancient roles for GT1-like genes and the trehalose pathway in regulating axillary meristem suppression, later recruited to mediate carpel suppression. Our findings expose hidden pleiotropy of classic maize genes and show how an ancient developmental program was redeployed to sculpt floral form.


Assuntos
Flores/crescimento & desenvolvimento , Flores/genética , Zea mays/crescimento & desenvolvimento , Zea mays/genética , Sequência de Aminoácidos , Apoptose , Flores/citologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genes de Plantas/genética , Inflorescência , Meristema/genética , Meristema/crescimento & desenvolvimento , Monoéster Fosfórico Hidrolases , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
15.
Proc Natl Acad Sci U S A ; 119(27): e2100036119, 2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35771940

RESUMO

Native Americans domesticated maize (Zea mays ssp. mays) from lowland teosinte parviglumis (Zea mays ssp. parviglumis) in the warm Mexican southwest and brought it to the highlands of Mexico and South America where it was exposed to lower temperatures that imposed strong selection on flowering time. Phospholipids are important metabolites in plant responses to low-temperature and phosphorus availability and have been suggested to influence flowering time. Here, we combined linkage mapping with genome scans to identify High PhosphatidylCholine 1 (HPC1), a gene that encodes a phospholipase A1 enzyme, as a major driver of phospholipid variation in highland maize. Common garden experiments demonstrated strong genotype-by-environment interactions associated with variation at HPC1, with the highland HPC1 allele leading to higher fitness in highlands, possibly by hastening flowering. The highland maize HPC1 variant resulted in impaired function of the encoded protein due to a polymorphism in a highly conserved sequence. A meta-analysis across HPC1 orthologs indicated a strong association between the identity of the amino acid at this position and optimal growth in prokaryotes. Mutagenesis of HPC1 via genome editing validated its role in regulating phospholipid metabolism. Finally, we showed that the highland HPC1 allele entered cultivated maize by introgression from the wild highland teosinte Zea mays ssp. mexicana and has been maintained in maize breeding lines from the Northern United States, Canada, and Europe. Thus, HPC1 introgressed from teosinte mexicana underlies a large metabolic QTL that modulates phosphatidylcholine levels and has an adaptive effect at least in part via induction of early flowering time.


Assuntos
Adaptação Fisiológica , Flores , Interação Gene-Ambiente , Fosfatidilcolinas , Fosfolipases A1 , Proteínas de Plantas , Zea mays , Alelos , Mapeamento Cromossômico , Flores/genética , Flores/metabolismo , Genes de Plantas , Ligação Genética , Fosfatidilcolinas/metabolismo , Fosfolipases A1/classificação , Fosfolipases A1/genética , Fosfolipases A1/metabolismo , Proteínas de Plantas/classificação , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Zea mays/genética , Zea mays/crescimento & desenvolvimento
16.
Thorax ; 79(5): 403-411, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38124220

RESUMO

INTRODUCTION: After puberty, females are more likely to develop asthma and in a more severe form than males. The associations between asthma and sex are complex with multiple intrinsic and external factors. AIM: To evaluate the sex differences in the characteristics and treatment of patients with severe asthma (SA) in a real-world setting. METHODS: Demographic, clinical and treatment characteristics for patients with SA in the UK Severe Asthma Registry (UKSAR) and Optimum Patient Care Research Database (OPCRD) were retrospectively analysed by sex using univariable and multivariable logistic regression analyses adjusted for year, age and hospital/practice. RESULTS: 3679 (60.9% female) patients from UKSAR and 18 369 patients (67.9% female) from OPCRD with SA were included. Females were more likely to be symptomatic with increased Asthma Control Questionnaire-6 (UKSAR adjusted OR (aOR) 1.14, 95% CI 1.09 to 1.18) and Royal College of Physicians-3 Question scores (OPCRD aOR 1.29, 95% CI 1.13 to 1.47). However, they had a higher forced expiratory volume in 1 second per cent (FEV1%) predicted (UKSAR 68.7% vs 64.8%, p<0.001) with no significant difference in peak expiratory flow. Type 2 biomarkers IgE (UKSAR 129 IU/mL vs 208 IU/mL, p<0.001) and FeNO (UKSAR 36ppb vs 46ppb, p<0.001) were lower in females with no significant difference in blood eosinophils or biological therapy. Females were less likely to be on maintenance oral corticosteroids (UKSAR aOR 0.86, 95% CI 0.75 to 0.99) but more likely to be obese (UKSAR aOR 1.67, 95% CI 145 to 1.93; OPCRD SA aOR 1.46, 95% CI 1.34 to 1.58). CONCLUSIONS: Females had increased symptoms and were more likely to be obese despite higher FEV1% predicted and lower type 2 biomarkers with consistent and clinically important differences across both datasets.


Assuntos
Asma , Humanos , Feminino , Masculino , Estudos Retrospectivos , Estudos Transversais , Asma/tratamento farmacológico , Asma/epidemiologia , Biomarcadores , Obesidade , Reino Unido/epidemiologia
17.
Development ; 148(3)2021 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-33462113

RESUMO

Macrophages are components of the innate immune system with key roles in tissue inflammation and repair. It is now evident that macrophages also support organogenesis, but few studies have characterized their identity, ontogeny and function during heart development. Here, we show that the distribution and prevalence of resident macrophages in the subepicardial compartment of the developing heart coincides with the emergence of new lymphatics, and that macrophages interact closely with the nascent lymphatic capillaries. Consequently, global macrophage deficiency led to extensive vessel disruption, with mutant hearts exhibiting shortened and mis-patterned lymphatics. The origin of cardiac macrophages was linked to the yolk sac and foetal liver. Moreover, the Cx3cr1+ myeloid lineage was found to play essential functions in the remodelling of the lymphatic endothelium. Mechanistically, macrophage hyaluronan was required for lymphatic sprouting by mediating direct macrophage-lymphatic endothelial cell interactions. Together, these findings reveal insight into the role of macrophages as indispensable mediators of lymphatic growth during the development of the mammalian cardiac vasculature.


Assuntos
Coração/crescimento & desenvolvimento , Vasos Linfáticos , Macrófagos/metabolismo , Animais , Receptor 1 de Quimiocina CX3C/genética , Adesão Celular , Linhagem Celular , Células Endoteliais , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Introdução de Genes , Humanos , Inflamação , Linfangiogênese , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Organogênese/genética , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/genética , Saco Vitelino
18.
Eur Respir J ; 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38575162

RESUMO

BACKGROUND: Pivotal Phase 3 trials and real-world studies have demonstrated benralizumab's overall efficacy and safety in severe eosinophilic asthma (SEA). Additional large-cohort data are needed to confirm its real-world effectiveness in SEA according to previous biologic use and key baseline characteristics important for treatment selection. METHODS: XALOC-1 is a large, multinational, retrospective, observational, real-world study programme of benralizumab in adults with SEA. This 48-week integrated analysis assessed annualised exacerbation rate (AER), maintenance oral corticosteroid (mOCS) use, asthma symptom control and lung function during a 12-month baseline period and up to 48 weeks after benralizumab initiation. Subgroup analyses were based on previous biologic use and key baseline clinical characteristics (mOCS use, blood eosinophil count, exacerbation history, age at asthma diagnosis, fractional exhaled nitric oxide level and presence of atopy and chronic rhinosinusitis with nasal polyps). RESULTS: Of 1002 patients analysed, 380 were biologic-experienced. At Week 48, 71.3% were exacerbation-free (versus 17.2% at baseline); relative reduction in AER was 82.7% overall and 72.9% in biologic-experienced patients; rates were maintained across all key clinical characteristic subgroups. Of patients using mOCS at baseline (n=274), 47.4% (130/274) eliminated their use by Week 48; the mean reduction from baseline in daily dose was 51.2% and, notably, 34.9% in biologic-experienced patients (n=115). Clinically significant improvements in asthma symptom control and lung function were observed. CONCLUSION: In this large, real-world programme, SEA patients treated with benralizumab had substantial improvements in clinical outcomes irrespective of previous biologic use and key clinical characteristics important to therapeutic decision-making in clinical practice.

19.
PLoS Pathog ; 18(10): e1010891, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36206307

RESUMO

Although antibody-inducing split virus vaccines (SV) are currently the most effective way to combat seasonal influenza, their efficacy can be modest, especially in immunologically-naïve individuals. We investigated immune responses towards inactivated whole influenza virus particle vaccine (WPV) formulations, predicated to be more immunogenic, in a non-human primate model, as an important step towards clinical testing in humans. Comprehensive analyses were used to capture 46 immune parameters to profile how WPV-induced responses differed to those elicited by antigenically-similar SV formulations. Naïve cynomolgus macaques vaccinated with either monovalent or quadrivalent WPV consistently induced stronger antibody responses and hemagglutination inhibition (HI) antibody titres against vaccine-matched viruses compared to SV formulations, while acute reactogenic effects were similar. Responses in WPV-primed animals were further increased by boosting with the same formulation, conversely to modest responses after priming and boosting with SV. 28-parameter multiplex bead array defined key antibody features and showed that while both WPV and SV induced elevated IgG responses against A/H1N1 nucleoprotein, only WPV increased IgG responses against A/H1N1 hemagglutinin (HA) and HA-Stem, and higher IgA responses to A/H1N1-HA after each vaccine dose. Antibodies to A/H1N1-HA and HA-Stem that could engage FcγR2a and FcγR3a were also present at higher levels after one dose of WPV compared to SV and remained elevated after the second dose. Furthermore, WPV-enhanced antibody responses were associated with higher frequencies of HA-specific B-cells and IFN-γ-producing CD4+ T-cell responses. Our data additionally demonstrate stronger boosting of HI titres by WPV following prior infection and support WPV administered as a priming dose irrespective of the follow up vaccine for the second dose. Our findings thus show that compared to SV vaccination, WPV-induced humoral responses are significantly increased in scope and magnitude, advocating WPV vaccination regimens for priming immunologically-naïve individuals and also in the event of a pandemic outbreak.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Vacinas contra Influenza , Influenza Humana , Animais , Humanos , Hemaglutininas , Anticorpos Antivirais , Vacinação , Testes de Inibição da Hemaglutinação , Vacinas de Produtos Inativados , Macaca fascicularis , Vírion , Imunoglobulina A , Imunoglobulina G , Nucleoproteínas
20.
Allergy ; 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38923444

RESUMO

BACKGROUND: Biologic asthma therapies reduce exacerbations and long-term oral corticosteroids (LTOCS) use in randomized controlled trials (RCTs); however, there are limited data on outcomes among patients ineligible for RCTs. Hence, we investigated responsiveness to biologics in a real-world population of adults with severe asthma. METHODS: Adults in the International Severe Asthma Registry (ISAR) with ≥24 weeks of follow-up were grouped into those who did, or did not, initiate biologics (anti-IgE, anti-IL5/IL5R, anti-IL4/13). Treatment responses were examined across four domains: forced expiratory volume in 1 second (FEV1) increase by ≥100 mL, improved asthma control, annualized exacerbation rate (AER) reduction ≥50%, and any LTOCS dose reduction. Super-response criteria were: FEV1 increase by ≥500 mL, new well-controlled asthma, no exacerbations, and LTOCS cessation or tapering to ≤5 mg/day. RESULTS: 5.3% of ISAR patients met basic RCT inclusion criteria; 2116/8451 started biologics. Biologic initiators had worse baseline impairment than non-initiators, despite having similar biomarker levels. Half or more of initiators had treatment responses: 59% AER reduction, 54% FEV1 increase, 49% improved control, 49% reduced LTOCS, of which 32%, 19%, 30%, and 39%, respectively, were super-responses. Responses/super-responses were more frequent in biologic initiators than in non-initiators; nevertheless, ~40-50% of initiators did not meet response criteria. CONCLUSIONS: Most patients with severe asthma are ineligible for RCTs of biologic therapies. Biologics are initiated in patients who have worse baseline impairments than non-initiators despite similar biomarker levels. Although biologic initiators exhibited clinical responses and super-responses in all outcome domains, 40-50% did not meet the response criteria.

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