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1.
Cell ; 186(12): 2672-2689.e25, 2023 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-37295404

RESUMO

Alphaviruses are RNA viruses that represent emerging public health threats. To identify protective antibodies, we immunized macaques with a mixture of western, eastern, and Venezuelan equine encephalitis virus-like particles (VLPs), a regimen that protects against aerosol challenge with all three viruses. Single- and triple-virus-specific antibodies were isolated, and we identified 21 unique binding groups. Cryo-EM structures revealed that broad VLP binding inversely correlated with sequence and conformational variability. One triple-specific antibody, SKT05, bound proximal to the fusion peptide and neutralized all three Env-pseudotyped encephalitic alphaviruses by using different symmetry elements for recognition across VLPs. Neutralization in other assays (e.g., chimeric Sindbis virus) yielded variable results. SKT05 bound backbone atoms of sequence-diverse residues, enabling broad recognition despite sequence variability; accordingly, SKT05 protected mice against Venezuelan equine encephalitis virus, chikungunya virus, and Ross River virus challenges. Thus, a single vaccine-elicited antibody can protect in vivo against a broad range of alphaviruses.


Assuntos
Alphavirus , Vírus da Encefalite Equina Venezuelana , Vacinas Virais , Animais , Camundongos , Vírus da Encefalite Equina Venezuelana/genética , Anticorpos Antivirais , Macaca
2.
Cell ; 178(3): 567-584.e19, 2019 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-31348886

RESUMO

The vaccine-mediated elicitation of antibodies (Abs) capable of neutralizing diverse HIV-1 strains has been a long-standing goal. To understand how broadly neutralizing antibodies (bNAbs) can be elicited, we identified, characterized, and tracked five neutralizing Ab lineages targeting the HIV-1-fusion peptide (FP) in vaccinated macaques over time. Genetic and structural analyses revealed two of these lineages to belong to a reproducible class capable of neutralizing up to 59% of 208 diverse viral strains. B cell analysis indicated each of the five lineages to have been initiated and expanded by FP-carrier priming, with envelope (Env)-trimer boosts inducing cross-reactive neutralization. These Abs had binding-energy hotspots focused on FP, whereas several FP-directed Abs induced by immunization with Env trimer-only were less FP-focused and less broadly neutralizing. Priming with a conserved subregion, such as FP, can thus induce Abs with binding-energy hotspots coincident with the target subregion and capable of broad neutralization.


Assuntos
Vacinas contra a AIDS/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Anti-HIV/imunologia , Peptídeos/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Neutralizantes/química , Anticorpos Neutralizantes/classificação , Linfócitos B/citologia , Linfócitos B/metabolismo , Cristalografia por Raios X , Feminino , Células HEK293 , Anticorpos Anti-HIV/química , Anticorpos Anti-HIV/classificação , HIV-1/metabolismo , Humanos , Macaca mulatta , Masculino , Peptídeos/química , Estrutura Terciária de Proteína , Produtos do Gene env do Vírus da Imunodeficiência Humana/química , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/metabolismo
3.
Cell ; 166(3): 609-623, 2016 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-27453470

RESUMO

Antibodies capable of neutralizing divergent influenza A viruses could form the basis of a universal vaccine. Here, from subjects enrolled in an H5N1 DNA/MIV-prime-boost influenza vaccine trial, we sorted hemagglutinin cross-reactive memory B cells and identified three antibody classes, each capable of neutralizing diverse subtypes of group 1 and group 2 influenza A viruses. Co-crystal structures with hemagglutinin revealed that each class utilized characteristic germline genes and convergent sequence motifs to recognize overlapping epitopes in the hemagglutinin stem. All six analyzed subjects had sequences from at least one multidonor class, and-in half the subjects-multidonor-class sequences were recovered from >40% of cross-reactive B cells. By contrast, these multidonor-class sequences were rare in published antibody datasets. Vaccination with a divergent hemagglutinin can thus increase the frequency of B cells encoding broad influenza A-neutralizing antibodies. We propose the sequence signature-quantified prevalence of these B cells as a metric to guide universal influenza A immunization strategies.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Vírus da Influenza A/imunologia , Vacinas contra Influenza/imunologia , Adulto , Sequência de Aminoácidos , Anticorpos Neutralizantes/química , Anticorpos Neutralizantes/genética , Anticorpos Antivirais/química , Anticorpos Antivirais/genética , Linfócitos B/imunologia , Epitopos de Linfócito B , Feminino , Rearranjo Gênico de Cadeia Pesada de Linfócito B , Humanos , Memória Imunológica , Virus da Influenza A Subtipo H5N1/imunologia , Masculino , Pessoa de Meia-Idade , Modelos Moleculares , Estrutura Terciária de Proteína , Relação Estrutura-Atividade , Adulto Jovem
4.
Immunity ; 54(2): 324-339.e8, 2021 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-33453152

RESUMO

Vaccine elicitation of broadly neutralizing antibodies (bnAbs) is a key HIV-research goal. The VRC01 class of bnAbs targets the CD4-binding site on the HIV-envelope trimer and requires extensive somatic hypermutation (SHM) to neutralize effectively. Despite substantial progress, vaccine-induced VRC01-class antibodies starting from unmutated precursors have exhibited limited neutralization breadth, particularly against viruses bearing glycan on loop D residue N276 (glycan276), present on most circulating strains. Here, using sequential immunization of immunoglobulin (Ig)-humanized mice expressing diverse unmutated VRC01-class antibody precursors, we elicited serum responses capable of neutralizing viruses bearing glycan276 and isolated multiple lineages of VRC01-class bnAbs, including two with >50% breadth on a 208-strain panel. Crystal structures of representative bnAbs revealed the same mode of recognition as known VRC01-class bnAbs. Structure-function studies further pinpointed key mutations and correlated their induction with specific immunizations. VRC01-class bnAbs can thus be matured by sequential immunization from unmutated ancestors to >50% breadth, and we delineate immunogens and regimens inducing key SHM.


Assuntos
Vacinas contra a AIDS/imunologia , Linfócitos B/imunologia , Anticorpos Amplamente Neutralizantes/metabolismo , Anticorpos Anti-HIV/metabolismo , Infecções por HIV/imunologia , HIV-1/fisiologia , Mutação/genética , Animais , Anticorpos Amplamente Neutralizantes/genética , Modelos Animais de Doenças , Células HEK293 , Anticorpos Anti-HIV/genética , Humanos , Ativação Linfocitária , Camundongos , Camundongos Transgênicos , Hipermutação Somática de Imunoglobulina , Vacinação
5.
Immunity ; 54(12): 2859-2876.e7, 2021 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-34788599

RESUMO

Repeat antigens, such as the Plasmodium falciparum circumsporozoite protein (PfCSP), use both sequence degeneracy and structural diversity to evade the immune response. A few PfCSP-directed antibodies have been identified that are effective at preventing malaria infection, including CIS43, but how these repeat-targeting antibodies might be improved has been unclear. Here, we engineered a humanized mouse model in which B cells expressed inferred human germline CIS43 (iGL-CIS43) B cell receptors and used both vaccination and bioinformatic analysis to obtain variant CIS43 antibodies with improved protective capacity. One such antibody, iGL-CIS43.D3, was significantly more potent than the current best-in-class PfCSP-directed antibody. We found that vaccination with a junctional epitope peptide was more effective than full-length PfCSP at recruiting iGL-CIS43 B cells to germinal centers. Structure-function analysis revealed multiple somatic hypermutations that combinatorically improved protection. This mouse model can thus be used to understand vaccine immunogens and to develop highly potent anti-malarial antibodies.


Assuntos
Subpopulações de Linfócitos B/imunologia , Epitopos/imunologia , Vacinas Antimaláricas/imunologia , Malária/imunologia , Plasmodium falciparum/fisiologia , Proteínas de Protozoários/imunologia , Vacinas de DNA/imunologia , Transferência Adotiva , Animais , Anticorpos Antiprotozoários/metabolismo , Modelos Animais de Doenças , Epitopos/genética , Engenharia Genética , Humanos , Evasão da Resposta Imune , Imunogenicidade da Vacina , Camundongos , Camundongos SCID , Proteínas de Protozoários/genética , Relação Estrutura-Atividade , Vacinação
6.
Immunity ; 54(4): 769-780.e6, 2021 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-33823129

RESUMO

An effective vaccine for respiratory syncytial virus (RSV) is an unrealized public health goal. A single dose of the prefusion-stabilized fusion (F) glycoprotein subunit vaccine (DS-Cav1) substantially increases serum-neutralizing activity in healthy adults. We sought to determine whether DS-Cav1 vaccination induces a repertoire mirroring the pre-existing diversity from natural infection or whether antibody lineages targeting specific epitopes predominate. We evaluated RSV F-specific B cell responses before and after vaccination in six participants using complementary B cell sequencing methodologies and identified 555 clonal lineages. DS-Cav1-induced lineages recognized the prefusion conformation of F (pre-F) and were genetically diverse. Expressed antibodies recognized all six antigenic sites on the pre-F trimer. We identified 34 public clonotypes, and structural analysis of two antibodies from a predominant clonotype revealed a common mode of recognition. Thus, vaccination with DS-Cav1 generates a diverse polyclonal response targeting the antigenic sites on pre-F, supporting the development and advanced testing of pre-F-based vaccines against RSV.


Assuntos
Anticorpos Antivirais/imunologia , Formação de Anticorpos/imunologia , Infecções por Vírus Respiratório Sincicial/imunologia , Vacinas contra Vírus Sincicial Respiratório/imunologia , Vírus Sincicial Respiratório Humano/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Neutralizantes/imunologia , Linhagem Celular , Linhagem Celular Tumoral , Criança , Pré-Escolar , Estudos de Coortes , Epitopos/imunologia , Feminino , Células HEK293 , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Vacinação/métodos , Proteínas Virais de Fusão/imunologia , Adulto Jovem
7.
Nature ; 618(7966): 808-817, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37344645

RESUMO

Niche signals maintain stem cells in a prolonged quiescence or transiently activate them for proper regeneration1. Altering balanced niche signalling can lead to regenerative disorders. Melanocytic skin nevi in human often display excessive hair growth, suggesting hair stem cell hyperactivity. Here, using genetic mouse models of nevi2,3, we show that dermal clusters of senescent melanocytes drive epithelial hair stem cells to exit quiescence and change their transcriptome and composition, potently enhancing hair renewal. Nevus melanocytes activate a distinct secretome, enriched for signalling factors. Osteopontin, the leading nevus signalling factor, is both necessary and sufficient to induce hair growth. Injection of osteopontin or its genetic overexpression is sufficient to induce robust hair growth in mice, whereas germline and conditional deletions of either osteopontin or CD44, its cognate receptor on epithelial hair cells, rescue enhanced hair growth induced by dermal nevus melanocytes. Osteopontin is overexpressed in human hairy nevi, and it stimulates new growth of human hair follicles. Although broad accumulation of senescent cells, such as upon ageing or genotoxic stress, is detrimental for the regenerative capacity of tissue4, we show that signalling by senescent cell clusters can potently enhance the activity of adjacent intact stem cells and stimulate tissue renewal. This finding identifies senescent cells and their secretome as an attractive therapeutic target in regenerative disorders.


Assuntos
Cabelo , Melanócitos , Transdução de Sinais , Animais , Camundongos , Cabelo/citologia , Cabelo/crescimento & desenvolvimento , Folículo Piloso/citologia , Folículo Piloso/fisiologia , Receptores de Hialuronatos/metabolismo , Melanócitos/citologia , Melanócitos/metabolismo , Nevo/metabolismo , Nevo/patologia , Osteopontina/metabolismo , Células-Tronco/citologia
8.
Immunity ; 50(3): 677-691.e13, 2019 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-30876875

RESUMO

Lineage-based vaccine design is an attractive approach for eliciting broadly neutralizing antibodies (bNAbs) against HIV-1. However, most bNAb lineages studied to date have features indicative of unusual recombination and/or development. From an individual in the prospective RV217 cohort, we identified three lineages of bNAbs targeting the membrane-proximal external region (MPER) of the HIV-1 envelope. Antibodies RV217-VRC42.01, -VRC43.01, and -VRC46.01 used distinct modes of recognition and neutralized 96%, 62%, and 30%, respectively, of a 208-strain virus panel. All three lineages had modest levels of somatic hypermutation and normal antibody-loop lengths and were initiated by the founder virus MPER. The broadest lineage, VRC42, was similar to the known bNAb 4E10. A multimeric immunogen based on the founder MPER activated B cells bearing the unmutated common ancestor of VRC42, with modest maturation of early VRC42 intermediates imparting neutralization breadth. These features suggest that VRC42 may be a promising template for lineage-based vaccine design.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Anti-HIV/imunologia , HIV-1/imunologia , Vacinas contra a AIDS/imunologia , Sequência de Aminoácidos , Linfócitos B/imunologia , Linhagem Celular , Células HEK293 , Infecções por HIV/imunologia , Humanos , Leucócitos Mononucleares , Estudos Longitudinais
9.
Immunity ; 48(3): 500-513.e6, 2018 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-29548671

RESUMO

Virtually the entire surface of the HIV-1-envelope trimer is recognized by neutralizing antibodies, except for a highly glycosylated region at the center of the "silent face" on the gp120 subunit. From an HIV-1-infected donor, #74, we identified antibody VRC-PG05, which neutralized 27% of HIV-1 strains. The crystal structure of the antigen-binding fragment of VRC-PG05 in complex with gp120 revealed an epitope comprised primarily of N-linked glycans from N262, N295, and N448 at the silent face center. Somatic hypermutation occurred preferentially at antibody residues that interacted with these glycans, suggesting somatic development of glycan recognition. Resistance to VRC-PG05 in donor #74 involved shifting of glycan-N448 to N446 or mutation of glycan-proximal residue E293. HIV-1 neutralization can thus be achieved at the silent face center by glycan-recognizing antibody; along with other known epitopes, the VRC-PG05 epitope completes coverage by neutralizing antibody of all major exposed regions of the prefusion closed trimer.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Anti-HIV/imunologia , Proteína gp120 do Envelope de HIV/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , Polissacarídeos/imunologia , Sequência de Aminoácidos , Anticorpos Neutralizantes/química , Anticorpos Neutralizantes/genética , Anticorpos Neutralizantes/metabolismo , Antígenos Virais/química , Antígenos Virais/imunologia , Sítios de Ligação , Mapeamento de Epitopos , Epitopos/química , Epitopos/imunologia , Epitopos/metabolismo , Glicopeptídeos/química , Glicopeptídeos/imunologia , Glicosilação , Anticorpos Anti-HIV/química , Anticorpos Anti-HIV/genética , Anticorpos Anti-HIV/metabolismo , Proteína gp120 do Envelope de HIV/química , Proteína gp120 do Envelope de HIV/metabolismo , Humanos , Modelos Moleculares , Conformação Molecular , Polissacarídeos/química , Ligação Proteica/imunologia , Hipermutação Somática de Imunoglobulina/imunologia , Relação Estrutura-Atividade
10.
EMBO J ; 40(7): e105846, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33469951

RESUMO

Protein termini are determinants of protein stability. Proteins bearing degradation signals, or degrons, at their amino- or carboxyl-termini are eliminated by the N- or C-degron pathways, respectively. We aimed to elucidate the function of C-degron pathways and to unveil how normal proteomes are exempt from C-degron pathway-mediated destruction. Our data reveal that C-degron pathways remove mislocalized cellular proteins and cleavage products of deubiquitinating enzymes. Furthermore, the C-degron and N-degron pathways cooperate in protein removal. Proteome analysis revealed a shortfall in normal proteins targeted by C-degron pathways, but not of defective proteins, suggesting proteolysis-based immunity as a constraint for protein evolution/selection. Our work highlights the importance of protein termini for protein quality surveillance, and the relationship between the functional proteome and protein degradation pathways.


Assuntos
Proteólise , Ubiquitinação , Motivos de Aminoácidos , Linhagem Celular Tumoral , Células HEK293 , Humanos , Transporte Proteico , Proteoma/química , Proteoma/metabolismo , Receptores de Citocinas/metabolismo
11.
Proc Natl Acad Sci U S A ; 119(35): e2208795119, 2022 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-36001691

RESUMO

The superior photosynthetic efficiency of C4 leaves over C3 leaves is owing to their unique Kranz anatomy, in which the vein is surrounded by one layer of bundle sheath (BS) cells and one layer of mesophyll (M) cells. Kranz anatomy development starts from three contiguous ground meristem (GM) cells, but its regulators and underlying molecular mechanism are largely unknown. To identify the regulators, we obtained the transcriptomes of 11 maize embryonic leaf cell types from five stages of pre-Kranz cells starting from median GM cells and six stages of pre-M cells starting from undifferentiated cells. Principal component and clustering analyses of transcriptomic data revealed rapid pre-Kranz cell differentiation in the first two stages but slow differentiation in the last three stages, suggesting early Kranz cell fate determination. In contrast, pre-M cells exhibit a more prolonged transcriptional differentiation process. Differential gene expression and coexpression analyses identified gene coexpression modules, one of which included 3 auxin transporter and 18 transcription factor (TF) genes, including known regulators of Kranz anatomy and/or vascular development. In situ hybridization of 11 TF genes validated their expression in early Kranz development. We determined the binding motifs of 15 TFs, predicted TF target gene relationships among the 18 TF and 3 auxin transporter genes, and validated 67 predictions by electrophoresis mobility shift assay. From these data, we constructed a gene regulatory network for Kranz development. Our study sheds light on the regulation of early maize leaf development and provides candidate leaf development regulators for future study.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Folhas de Planta , Transcriptoma , Zea mays , Ácidos Indolacéticos/metabolismo , Microdissecção e Captura a Laser , Fotossíntese/genética , Folhas de Planta/embriologia , Folhas de Planta/genética , Zea mays/enzimologia , Zea mays/genética
12.
J Neurosci ; 43(35): 6185-6196, 2023 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-37541835

RESUMO

Age-related impairments in value representations and updating during decision-making and reward-based learning are often related to age-related attenuation in the catecholamine system such as dopamine (DA) and norepinephrine (NE). However, it is unclear to what extent age-related declines in NE functioning in humans affect reward-based decision-making. We conducted a probabilistic decision-making task and applied a Q-learning model to investigate participants' anticipatory values and value sensitivities. Task-related pupil dilations and locus coeruleus (LC) magnetic resonance imaging (MRI) contrast, which served as a potential window of the LC-NE functions, were assessed in younger and older adults. Results showed that in both choice and feedback phases, younger adults' (N = 42, 22 males) pupil dilations negatively correlated with anticipatory values, indicating uncertainty about outcome probabilities. Uncertainty-evoked pupil dilations in older adults (N = 41, 27 males) were smaller, indicating age-related impairments in value estimation and updating. In both age groups, participants who showed a larger uncertainty-evoked pupil dilation exhibited a higher value sensitivity as reflected in the ß parameter of the reinforcement Q-learning model. Furthermore, older adults (N = 34, 29 males) showed a lower LC-MRI contrast than younger adults (N = 25, 15 males). The LC-MRI contrast positively correlated with value sensitivity only in older but not in younger adults. These findings suggest that task-related pupillary responses can reflect age-related deficits in value estimation and updating during reward-based decision-making. Our evidence with the LC-MRI contrast further showed the age-related decline of the LC structure in modulating value representations during reward-based learning.SIGNIFICANCE STATEMENT Age-related impairments in value representation and updating during reward-based learning are associated with declines in the catecholamine modulation with age. However, it is unclear how age-related declines in the LC-NE system may affect reward-based learning. Here, we show that compared with younger adults, older adults exhibited reduced uncertainty-induced pupil dilations, suggesting age-related deficits in value estimation and updating. Older adults showed a lower structural MRI of the LC contrast than younger adults, indicating age-related degeneration of the LC structure. The association between the LC-MRI contrast and value sensitivity was only observed in older adults. Our findings may demonstrate a pioneering model to unravel the role of the LC-NE system in reward-based learning in aging.


Assuntos
Locus Cerúleo , Recompensa , Masculino , Humanos , Idoso , Locus Cerúleo/diagnóstico por imagem , Locus Cerúleo/fisiologia , Aprendizagem , Reforço Psicológico , Catecolaminas
13.
BMC Bioinformatics ; 25(1): 209, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38867193

RESUMO

BACKGROUND: Single-cell RNA sequencing (sc-RNASeq) data illuminate transcriptomic heterogeneity but also possess a high level of noise, abundant missing entries and sometimes inadequate or no cell type annotations at all. Bulk-level gene expression data lack direct information of cell population composition but are more robust and complete and often better annotated. We propose a modeling framework to integrate bulk-level and single-cell RNASeq data to address the deficiencies and leverage the mutual strengths of each type of data and enable a more comprehensive inference of their transcriptomic heterogeneity. Contrary to the standard approaches of factorizing the bulk-level data with one algorithm and (for some methods) treating single-cell RNASeq data as references to decompose bulk-level data, we employed multiple deconvolution algorithms to factorize the bulk-level data, constructed the probabilistic graphical models of cell-level gene expressions from the decomposition outcomes, and compared the log-likelihood scores of these models in single-cell data. We term this framework backward deconvolution as inference operates from coarse-grained bulk-level data to fine-grained single-cell data. As the abundant missing entries in sc-RNASeq data have a significant effect on log-likelihood scores, we also developed a criterion for inclusion or exclusion of zero entries in log-likelihood score computation. RESULTS: We selected nine deconvolution algorithms and validated backward deconvolution in five datasets. In the in-silico mixtures of mouse sc-RNASeq data, the log-likelihood scores of the deconvolution algorithms were strongly anticorrelated with their errors of mixture coefficients and cell type specific gene expression signatures. In the true bulk-level mouse data, the sample mixture coefficients were unknown but the log-likelihood scores were strongly correlated with accuracy rates of inferred cell types. In the data of autism spectrum disorder (ASD) and normal controls, we found that ASD brains possessed higher fractions of astrocytes and lower fractions of NRGN-expressing neurons than normal controls. In datasets of breast cancer and low-grade gliomas (LGG), we compared the log-likelihood scores of three simple hypotheses about the gene expression patterns of the cell types underlying the tumor subtypes. The model that tumors of each subtype were dominated by one cell type persistently outperformed an alternative model that each cell type had elevated expression in one gene group and tumors were mixtures of those cell types. Superiority of the former model is also supported by comparing the real breast cancer sc-RNASeq clusters with those generated by simulated sc-RNASeq data. CONCLUSIONS: The results indicate that backward deconvolution serves as a sensible model selection tool for deconvolution algorithms and facilitates discerning hypotheses about cell type compositions underlying heterogeneous specimens such as tumors.


Assuntos
Algoritmos , Análise de Sequência de RNA , Análise de Célula Única , Transcriptoma , Análise de Célula Única/métodos , Análise de Sequência de RNA/métodos , Transcriptoma/genética , Humanos , Perfilação da Expressão Gênica/métodos , Animais , Camundongos , Análise da Expressão Gênica de Célula Única
14.
BMC Plant Biol ; 24(1): 155, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38424508

RESUMO

BACKGROUND: Powdery mildew (PM) is one of the important soybean diseases, and host resistance could practically contribute to soybean PM management. To date, only the Rmd locus on chromosome (Chr) 16 was identified through traditional QTL mapping and GWAS, and it remains unclear if the bulk segregant RNA-Seq (BSR-Seq) methodology is feasible to explore additional PM resistance that might exist in other varieties. RESULTS: BSR-Seq was applied to contrast genotypes and gene expressions between the resistant bulk (R bulk) and the susceptible bulk (S bulk), as well as the parents. The ∆(SNP-index) and G' value identified several QTL and significant SNPs/Indels on Chr06, Chr15, and Chr16. Differentially expressed genes (DEGs) located within these QTL were identified using HISAT2 and Kallisto, and allele-specific primers (AS-primers) were designed to validate the accuracy of phenotypic prediction. While the AS-primers on Chr06 or Chr15 cannot distinguish the resistant and susceptible phenotypes, AS-primers on Chr16 exhibited 82% accuracy prediction with an additive effect, similar to the SSR marker Satt431. CONCLUSIONS: Evaluation of additional AS-primers in the linkage disequilibrium (LD) block on Chr16 further confirmed the resistant locus, derived from the resistant parental variety 'Kaohsiung 11' ('KS11'), not only overlaps with the Rmd locus with unique up-regulated LRR genes (Glyma.16G213700 and Glyma.16G215100), but also harbors a down-regulated MLO gene (Glyma.16G145600). Accordingly, this study exemplified the feasibility of BSR-Seq in studying biotrophic disease resistance in soybean, and showed the genetic makeup of soybean variety 'KS11' comprising the Rmd locus and one MLO gene.


Assuntos
Resistência à Doença , Glycine max , Glycine max/genética , RNA-Seq , Alelos , Mapeamento Cromossômico/métodos , Fenótipo , Resistência à Doença/genética , Erysiphe , Doenças das Plantas/genética
15.
J Virol ; 97(5): e0160422, 2023 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-37098956

RESUMO

While neutralizing antibodies that target the HIV-1 fusion peptide have been elicited in mice by vaccination, antibodies reported thus far have been from only a single antibody class that could neutralize ~30% of HIV-1 strains. To explore the ability of the murine immune system to generate cross-clade neutralizing antibodies and to investigate how higher breadth and potency might be achieved, we tested 17 prime-boost regimens that utilized diverse fusion peptide-carrier conjugates and HIV-1 envelope trimers with different fusion peptides. We observed priming in mice with fusion peptide-carrier conjugates of variable peptide length to elicit higher neutralizing responses, a result we confirmed in guinea pigs. From vaccinated mice, we isolated 21 antibodies, belonging to 4 distinct classes of fusion peptide-directed antibodies capable of cross-clade neutralization. Top antibodies from each class collectively neutralized over 50% of a 208-strain panel. Structural analyses - both X-ray and cryo-EM - revealed each antibody class to recognize a distinct conformation of fusion peptide and to have a binding pocket capable of accommodating diverse fusion peptides. Murine vaccinations can thus elicit diverse neutralizing antibodies, and altering peptide length during prime can improve the elicitation of cross-clade responses targeting the fusion peptide site of HIV-1 vulnerability. IMPORTANCE The HIV-1 fusion peptide has been identified as a site for elicitation of broadly neutralizing antibodies, with prior studies demonstrating that priming with fusion peptide-based immunogens and boosting with soluble envelope (Env) trimers can elicit cross-clade HIV-1-neutralizing responses. To improve the neutralizing breadth and potency of fusion peptide-directed responses, we evaluated vaccine regimens that incorporated diverse fusion peptide-conjugates and Env trimers with variation in fusion peptide length and sequence. We found that variation in peptide length during prime elicits enhanced neutralizing responses in mice and guinea pigs. We identified vaccine-elicited murine monoclonal antibodies from distinct classes capable of cross-clade neutralization and of diverse fusion peptide recognition. Our findings lend insight into improved immunogens and regimens for HIV-1 vaccine development.


Assuntos
Vacinas contra a AIDS , Infecções por HIV , Soropositividade para HIV , HIV-1 , Animais , Cobaias , Camundongos , Anticorpos Anti-HIV , Isotipos de Imunoglobulinas , Vacinação , Peptídeos , Anticorpos Neutralizantes , Anticorpos Amplamente Neutralizantes , Produtos do Gene env do Vírus da Imunodeficiência Humana , Infecções por HIV/prevenção & controle
16.
J Pathol ; 259(3): 276-290, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36441149

RESUMO

Interstitial cystitis/bladder pain syndrome with Hunner's lesion (HIC) is characterized by chronic inflammation and nerve hyperplasia; however, the pathogenesis of HIC remains a mystery. In this study, we detected both Epstein-Barr virus (EBV) latency infection genes EBNA-1 and LMP-1 and EBV lytic infection BZLF-1 and BRLF-1 expression in the HIC bladders, indicating the coexistence of EBV persistence and reactivation in the B cells in HIC bladders. Upregulation of EBV-associated inflammatory genes in HIC bladders, such as TNF-α and IL-6, suggests EBV infection is implicated in the pathogenesis of bladder inflammation. Nerve hyperplasia and upregulation of brain-derived neurotrophic factor (BDNF) were noted in the HIC bladders. Double immunochemical staining and flow cytometry revealed the origin of BDNF to be EBV-infected B cells. Inducible BDNF expression was noted in B cells upon EBV infection, but not in the T cells. A chromatin immunoprecipitation study revealed BDNF transcription could be promoted by cooperation between EBV nuclear antigens, chromatin modifiers, and B-cell-specific transcription. Knockdown of BDNF in EBV-infected B cells resulted in the inhibition of cell proliferation and viability. Downregulation of phosphorylated SMAD2 and STAT3 after BDNF knockdown may play a role in the mechanism. Implantation of latent EBV-infected B cells into rat bladder walls resulted in a higher expression level of CD45 and PGP9.5, suggesting tissue inflammation and nerve hyperplasia. In contrast, implantation of BDNF depleted EBV-infected B cells abrogated these effects. This is the first study to provide insights into the mechanisms underlying the involvement of EBV-infected B cells in HIC pathogenesis. © 2022 The Pathological Society of Great Britain and Ireland.


Assuntos
Cistite Intersticial , Cistite , Infecções por Vírus Epstein-Barr , Animais , Ratos , Cistite Intersticial/genética , Cistite Intersticial/complicações , Cistite Intersticial/metabolismo , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/genética , Fator Neurotrófico Derivado do Encéfalo/genética , Hiperplasia , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/metabolismo , Cistite/complicações , Antígenos Nucleares do Vírus Epstein-Barr/metabolismo , Proteínas Virais/metabolismo , Inflamação/complicações
17.
Future Oncol ; 20(9): 493-505, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37882449

RESUMO

Poly(ADP-ribose) polymerase inhibitors in combination with androgen-receptor signaling inhibitors are a promising therapeutic option for patients with metastatic castration-sensitive prostate cancer (mCSPC) and homologous recombination repair (HRR) gene alterations. Here, we describe the design and rationale of the multinational, phase III, TALAPRO-3 study comparing talazoparib plus enzalutamide versus placebo plus enzalutamide in patients with mCSPC and HRR gene alterations. The primary end point is investigator-assessed radiographic progression-free survival (rPFS) per RECIST 1.1 in soft tissue, or per PCWG3 criteria in bone. The TALAPRO-3 study will demonstrate whether the addition of talazoparib can improve the efficacy of enzalutamide as assessed by rPFS in patients with mCSPC and HRR gene alterations undergoing androgen deprivation therapy. Clinical Trial Registration:NCT04821622 (ClinicalTrials.gov) Registry Name: Study of Talazoparib With Enzalutamide in Men With DDR Gene Mutated mCSPC. Date of Registration: 29 March 2021.


Assuntos
Benzamidas , Feniltioidantoína , Ftalazinas , Neoplasias de Próstata Resistentes à Castração , Masculino , Humanos , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/genética , Antagonistas de Androgênios/uso terapêutico , Androgênios , Nitrilas/uso terapêutico , Castração , Ensaios Clínicos Fase III como Assunto
18.
Med Sci Monit ; 30: e943493, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38523334

RESUMO

BACKGROUND Care bundles for infection control consist of a set of evidence-based measures to prevent infections. This retrospective study aimed to compare surgical site infections (SSIs) from a single hospital surveillance system between 2017 and 2020, before and after implementing a standardized care bundle across specialties in 2019. It also aimed to assess whether bundle compliance affects the rate of SSIs. MATERIAL AND METHODS A care bundle consisting of 4 components (peri-operative antibiotics use, peri-operative glycemic control, pre-operative skin preparation, and maintaining intra-operative body temperature) was launched in 2019. We compared the incidence rates of SSIs, standardized infection ratio (SIR), and clinical outcomes of surgical procedures enrolled in the surveillance system before and after introducing the bundle care. The level of bundle compliance, defined as the number of fully implemented bundle components, was evaluated. RESULTS We included 6059 procedures, with 2010 in the pre-bundle group and 4049 in the post-bundle group. Incidence rates of SSIs (1.7% vs 1.0%, P=0.013) and SIR (0.8 vs 1.48, P<0.01) were significantly lower in the post-bundle group. The incidence of SSIs was significantly lower when all bundle components were fully adhered to, compared with when only half of the components were adhered to (0.3% vs 4.0%, P<0.01). CONCLUSIONS SSIs decreased significantly after the application of a standardized care bundle for surgical procedures across specialties. Full adherence to all bundle components was the key to effectively reducing the risk of surgical site infections.


Assuntos
Pacotes de Assistência ao Paciente , Infecção da Ferida Cirúrgica , Humanos , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/prevenção & controle , Infecção da Ferida Cirúrgica/etiologia , Estudos Retrospectivos , Antibacterianos , Pacotes de Assistência ao Paciente/efeitos adversos , Pacotes de Assistência ao Paciente/métodos , Controle de Infecções/métodos
19.
BMC Public Health ; 24(1): 720, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38448843

RESUMO

BACKGROUND: Well-being is an important issue in workplace. One of these assessment tools of well-being, Workplace PERMA Profiler, is based on Seligman's five dimensions well-being. Prolonged fatigue may last for a long time, leading a great impact on both employees and enterprises. However, rare studies about the association between well-being and fatigue had been investigated. Our aim is to establish the Chinese version Profiler, and to discovery the association between workplace well-being and fatigue. METHODS: The Chinese version was established according to International Society of Pharmacoeconomics and Outcomes Research (ISPOR) task force guidelines. In the study, researchers employed simple random sampling by approaching individuals undergoing health checkups or receiving workplace health services, inviting them to participate in a questionnaire-based interview. Prolonged Fatigue was evaluated by Checklist Individual Strength (CIS). The reliability was evaluated by Cronbach's alphas, Intra-class Correlation Coefficients (ICCs), and measurement errors. Moreover, confirmatory factor analysis and correlational analyses were assessed for the validity. RESULTS: The analyses included 312 Chinese workers. Cronbach's alphas of the Chinese version ranged from 0.69 to 0.93, while the ICC ranged from 0.70 to 0.92. The 5-factor model of confirmatory factor analysis revealed a nearly appropriate fit (χ2 (82) = 346.560, Comparative Fit Index [CFI] = 0.887, Tucker-Lewis Index [TLI] = 0.855, Root Mean Square Error of Approximation [RMSEA] = 0.114, Standardized Root Mean Square Residual [SRMR] = 0.060). Moreover, the CIS and its four dimensions were significantly and negatively associated with the Positive Emotion, while they are positively associated with Engagement dimension except CIS-Motivation dimension. CONCLUSION: The Chinese version Workplace PERMA-Profiler indicate nice reliability and validity. Furthermore, all CIS dimensions were negatively influenced by Positive Emotion, while commonly positively associated with Engagement.


Assuntos
Comitês Consultivos , Local de Trabalho , Humanos , Povo Asiático , Fadiga , Reprodutibilidade dos Testes
20.
Proc Natl Acad Sci U S A ; 118(39)2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34551978

RESUMO

Human metapneumovirus (HMPV) is a major cause of respiratory disease worldwide, particularly among children and the elderly. Although there is no licensed HMPV vaccine, promising candidates have been identified for related pneumoviruses based on the structure-based stabilization of the fusion (F) glycoprotein trimer, with prefusion-stabilized F glycoprotein trimers eliciting significantly higher neutralizing responses than their postfusion F counterparts. However, immunization with HMPV F trimers in either prefusion or postfusion conformations has been reported to elicit equivalent neutralization responses. Here we investigate the impact of stabilizing disulfides, especially interprotomer disulfides (IP-DSs) linking protomers of the F trimer, on the elicitation of HMPV-neutralizing responses. We designed F trimer disulfides, screened for their expression, and used electron microscopy (EM) to confirm their formation, including that of an unexpected postfusion variant. In mice, IP-DS-stabilized prefusion and postfusion HMPV F elicited significantly higher neutralizing responses than non-IP-DS-stabilized HMPV Fs. In macaques, the impact of IP-DS stabilization was more measured, although IP-DS-stabilized variants of either prefusion or postfusion HMPV F induced neutralizing responses many times the average titers observed in a healthy human cohort. Serological and absorption-based analyses of macaque responses revealed elicited HMPV-neutralizing responses to be absorbed differently by IP-DS-containing and by non-IP-DS-containing postfusion Fs, suggesting IP-DS stabilization to alter not only the immunogenicity of select epitopes but their antigenicity as well. We speculate the observed increase in immunogenicity by IP-DS trimers to be related to reduced interprotomer flexibility within the HMPV F trimer.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Dissulfetos/química , Epitopos/imunologia , Glicoproteínas/imunologia , Metapneumovirus/imunologia , Mutação , Animais , Glicoproteínas/genética , Humanos , Imunização , Macaca , Metapneumovirus/genética , Camundongos , Regiões Promotoras Genéticas
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