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1.
Cell ; 184(9): 2332-2347.e16, 2021 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-33761326

RESUMO

The SARS-CoV-2 spike (S) glycoprotein contains an immunodominant receptor-binding domain (RBD) targeted by most neutralizing antibodies (Abs) in COVID-19 patient plasma. Little is known about neutralizing Abs binding to epitopes outside the RBD and their contribution to protection. Here, we describe 41 human monoclonal Abs (mAbs) derived from memory B cells, which recognize the SARS-CoV-2 S N-terminal domain (NTD) and show that a subset of them neutralize SARS-CoV-2 ultrapotently. We define an antigenic map of the SARS-CoV-2 NTD and identify a supersite (designated site i) recognized by all known NTD-specific neutralizing mAbs. These mAbs inhibit cell-to-cell fusion, activate effector functions, and protect Syrian hamsters from SARS-CoV-2 challenge, albeit selecting escape mutants in some animals. Indeed, several SARS-CoV-2 variants, including the B.1.1.7, B.1.351, and P.1 lineages, harbor frequent mutations within the NTD supersite, suggesting ongoing selective pressure and the importance of NTD-specific neutralizing mAbs for protective immunity and vaccine design.


Assuntos
Antígenos Virais/imunologia , SARS-CoV-2/imunologia , Animais , Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , COVID-19/imunologia , COVID-19/virologia , Cricetinae , Mapeamento de Epitopos , Variação Genética , Modelos Moleculares , Mutação/genética , Testes de Neutralização , Domínios Proteicos , RNA Viral/genética , SARS-CoV-2/isolamento & purificação , SARS-CoV-2/ultraestrutura
2.
Nature ; 621(7979): 592-601, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37648855

RESUMO

Currently circulating SARS-CoV-2 variants have acquired convergent mutations at hot spots in the receptor-binding domain1 (RBD) of the spike protein. The effects of these mutations on viral infection and transmission and the efficacy of vaccines and therapies remains poorly understood. Here we demonstrate that recently emerged BQ.1.1 and XBB.1.5 variants bind host ACE2 with high affinity and promote membrane fusion more efficiently than earlier Omicron variants. Structures of the BQ.1.1, XBB.1 and BN.1 RBDs bound to the fragment antigen-binding region of the S309 antibody (the parent antibody for sotrovimab) and human ACE2 explain the preservation of antibody binding through conformational selection, altered ACE2 recognition and immune evasion. We show that sotrovimab binds avidly to all Omicron variants, promotes Fc-dependent effector functions and protects mice challenged with BQ.1.1 and hamsters challenged with XBB.1.5. Vaccine-elicited human plasma antibodies cross-react with and trigger effector functions against current Omicron variants, despite a reduced neutralizing activity, suggesting a mechanism of protection against disease, exemplified by S309. Cross-reactive RBD-directed human memory B cells remained dominant even after two exposures to Omicron spikes, underscoring the role of persistent immune imprinting.


Assuntos
Anticorpos Neutralizantes , COVID-19 , SARS-CoV-2 , Animais , Cricetinae , Humanos , Camundongos , Enzima de Conversão de Angiotensina 2/imunologia , Enzima de Conversão de Angiotensina 2/metabolismo , Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/química , Anticorpos Neutralizantes/imunologia , COVID-19/imunologia , COVID-19/prevenção & controle , COVID-19/virologia , Reações Cruzadas , Evasão da Resposta Imune , Fusão de Membrana , Testes de Neutralização , SARS-CoV-2/classificação , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Mutação , Células B de Memória/imunologia , Vacinas contra COVID-19/imunologia
3.
Nature ; 598(7880): 342-347, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34464958

RESUMO

SARS-CoV-2 infection-which involves both cell attachment and membrane fusion-relies on the angiotensin-converting enzyme 2 (ACE2) receptor, which is paradoxically found at low levels in the respiratory tract1-3, suggesting that there may be additional mechanisms facilitating infection. Here we show that C-type lectin receptors, DC-SIGN, L-SIGN and the sialic acid-binding immunoglobulin-like lectin 1 (SIGLEC1) function as attachment receptors by enhancing ACE2-mediated infection and modulating the neutralizing activity of different classes of spike-specific antibodies. Antibodies to the amino-terminal domain or to the conserved site at the base of the receptor-binding domain, while poorly neutralizing infection of ACE2-overexpressing cells, effectively block lectin-facilitated infection. Conversely, antibodies to the receptor binding motif, while potently neutralizing infection of ACE2-overexpressing cells, poorly neutralize infection of cells expressing DC-SIGN or L-SIGN and trigger fusogenic rearrangement of the spike, promoting cell-to-cell fusion. Collectively, these findings identify a lectin-dependent pathway that enhances ACE2-dependent infection by SARS-CoV-2 and reveal distinct mechanisms of neutralization by different classes of spike-specific antibodies.


Assuntos
Anticorpos Neutralizantes/imunologia , Lectinas/metabolismo , SARS-CoV-2/metabolismo , SARS-CoV-2/patogenicidade , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , Moléculas de Adesão Celular/metabolismo , Fusão Celular , Linhagem Celular , Cricetinae , Feminino , Humanos , Lectinas/imunologia , Lectinas Tipo C/metabolismo , Fusão de Membrana , Receptores de Superfície Celular/metabolismo , SARS-CoV-2/imunologia , Lectina 1 Semelhante a Ig de Ligação ao Ácido Siálico/metabolismo , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/metabolismo
4.
Nature ; 597(7874): 103-108, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34280951

RESUMO

The recent emergence of SARS-CoV-2 variants of concern1-10 and the recurrent spillovers of coronaviruses11,12 into the human population highlight the need for broadly neutralizing antibodies that are not affected by the ongoing antigenic drift and that can prevent or treat future zoonotic infections. Here we describe a human monoclonal antibody designated S2X259, which recognizes a highly conserved cryptic epitope of the receptor-binding domain and cross-reacts with spikes from all clades of sarbecovirus. S2X259 broadly neutralizes spike-mediated cell entry of SARS-CoV-2, including variants of concern (B.1.1.7, B.1.351, P.1, and B.1.427/B.1.429), as well as a wide spectrum of human and potentially zoonotic sarbecoviruses through inhibition of angiotensin-converting enzyme 2 (ACE2) binding to the receptor-binding domain. Furthermore, deep-mutational scanning and in vitro escape selection experiments demonstrate that S2X259 possesses an escape profile that is limited to a single substitution, G504D. We show that prophylactic and therapeutic administration of S2X259 protects Syrian hamsters (Mesocricetus auratus) against challenge with the prototypic SARS-CoV-2 and the B.1.351 variant of concern, which suggests that this monoclonal antibody is a promising candidate for the prevention and treatment of emergent variants and zoonotic infections. Our data reveal a key antigenic site that is targeted by broadly neutralizing antibodies and will guide the design of vaccines that are effective against all sarbecoviruses.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/uso terapêutico , Anticorpos Antivirais/imunologia , Anticorpos Amplamente Neutralizantes/imunologia , Anticorpos Amplamente Neutralizantes/uso terapêutico , COVID-19/prevenção & controle , SARS-CoV-2/classificação , SARS-CoV-2/imunologia , Animais , Anticorpos Monoclonais/química , Anticorpos Antivirais/química , Anticorpos Antivirais/uso terapêutico , Anticorpos Amplamente Neutralizantes/química , COVID-19/imunologia , COVID-19/virologia , Reações Cruzadas/imunologia , Modelos Animais de Doenças , Feminino , Humanos , Evasão da Resposta Imune/genética , Evasão da Resposta Imune/imunologia , Mesocricetus/imunologia , Mesocricetus/virologia , Mutação , Testes de Neutralização , SARS-CoV-2/química , SARS-CoV-2/genética , Zoonoses Virais/imunologia , Zoonoses Virais/prevenção & controle , Zoonoses Virais/virologia
5.
Nature ; 597(7874): 97-102, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34261126

RESUMO

An ideal therapeutic anti-SARS-CoV-2 antibody would resist viral escape1-3, have activity against diverse sarbecoviruses4-7, and be highly protective through viral neutralization8-11 and effector functions12,13. Understanding how these properties relate to each other and vary across epitopes would aid the development of therapeutic antibodies and guide vaccine design. Here we comprehensively characterize escape, breadth and potency across a panel of SARS-CoV-2 antibodies targeting the receptor-binding domain (RBD). Despite a trade-off between in vitro neutralization potency and breadth of sarbecovirus binding, we identify neutralizing antibodies with exceptional sarbecovirus breadth and a corresponding resistance to SARS-CoV-2 escape. One of these antibodies, S2H97, binds with high affinity across all sarbecovirus clades to a cryptic epitope and prophylactically protects hamsters from viral challenge. Antibodies that target the angiotensin-converting enzyme 2 (ACE2) receptor-binding motif (RBM) typically have poor breadth and are readily escaped by mutations despite high neutralization potency. Nevertheless, we also characterize a potent RBM antibody (S2E128) with breadth across sarbecoviruses related to SARS-CoV-2 and a high barrier to viral escape. These data highlight principles underlying variation in escape, breadth and potency among antibodies that target the RBD, and identify epitopes and features to prioritize for therapeutic development against the current and potential future pandemics.


Assuntos
Anticorpos Amplamente Neutralizantes/imunologia , COVID-19/virologia , Reações Cruzadas/imunologia , Evasão da Resposta Imune , SARS-CoV-2/classificação , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/imunologia , Adulto , Idoso , Animais , Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/química , Anticorpos Antivirais/imunologia , Afinidade de Anticorpos , Anticorpos Amplamente Neutralizantes/química , COVID-19/imunologia , Vacinas contra COVID-19/química , Vacinas contra COVID-19/imunologia , Linhagem Celular , Cricetinae , Epitopos de Linfócito B/química , Epitopos de Linfócito B/genética , Epitopos de Linfócito B/imunologia , Feminino , Humanos , Evasão da Resposta Imune/genética , Evasão da Resposta Imune/imunologia , Masculino , Mesocricetus , Pessoa de Meia-Idade , Modelos Moleculares , SARS-CoV-2/química , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética , Vacinologia , Tratamento Farmacológico da COVID-19
6.
Proc Natl Acad Sci U S A ; 121(28): e2314320121, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38954540

RESUMO

Liquid-phase electron microscopy (LP-EM) imaging has revolutionized our understanding of nanosynthesis and assembly. However, the current closed geometry limits its application for open systems. The ubiquitous physical process of the coffee-ring phenomenon that underpins materials and engineering science remains elusive at the nanoscale due to the lack of experimental tools. We introduce a quartz nanopipette liquid cell with a tunable dimension that requires only standard microscopes. Depending on the imaging condition, the open geometry of the nanopipette allows the imaging of evaporation-induced pattern formation, but it can also function as an ordinary closed-geometry liquid cell where evaporation is negligible despite the nano opening. The nano coffee-ring phenomenon was observed by tracking individual nanoparticles in an evaporating nanodroplet created from a thin liquid film by interfacial instability. Nanoflows drive the assembly and disruption of a ring pattern with the absence of particle-particle correlations. With surface effects, nanoflows override thermal fluctuations at tens of nanometers, in which nanoparticles displayed a "drunken man trajectory" and performed work at a value much smaller than kBT.

7.
Proc Natl Acad Sci U S A ; 121(24): e2319179121, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38833467

RESUMO

To test the hypothesis that early-life adversity accelerates the pace of biological aging, we analyzed data from the Dutch Hunger Winter Families Study (DHWFS, N = 951). DHWFS is a natural-experiment birth-cohort study of survivors of in-utero exposure to famine conditions caused by the German occupation of the Western Netherlands in Winter 1944 to 1945, matched controls, and their siblings. We conducted DNA methylation analysis of blood samples collected when the survivors were aged 58 to quantify biological aging using the DunedinPACE, GrimAge, and PhenoAge epigenetic clocks. Famine survivors had faster DunedinPACE, as compared with controls. This effect was strongest among women. Results were similar for GrimAge, although effect-sizes were smaller. We observed no differences in PhenoAge between survivors and controls. Famine effects were not accounted for by blood-cell composition and were similar for individuals exposed early and later in gestation. Findings suggest in-utero undernutrition may accelerate biological aging in later life.


Assuntos
Envelhecimento , Metilação de DNA , Fome Epidêmica , Efeitos Tardios da Exposição Pré-Natal , Humanos , Feminino , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Gravidez , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Masculino , Epigênese Genética , Inanição
8.
Proc Natl Acad Sci U S A ; 120(7): e2212212120, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36745802

RESUMO

During vertebrate embryogenesis, hematopoietic stem and progenitor cell (HSPC) production through endothelial-to-hematopoietic transition requires suitable developmental signals, but how these signals are accurately regulated remains incompletely understood. Cytoplasmic polyadenylation, which is one of the posttranscriptional regulations, plays a crucial role in RNA metabolism. Here, we report that Cpeb1b-mediated cytoplasmic polyadenylation is important for HSPC specification by translational control of Hedgehog (Hh) signaling during zebrafish early development. Cpeb1b is highly expressed in notochord and its deficiency results in defective HSPC production. Mechanistically, Cpeb1b regulates hemogenic endothelium specification by the Hedgehog-Vegf-Notch axis. We demonstrate that the cytoplasmic polyadenylation element motif-dependent interaction between Cpeb1b and shha messenger RNA (mRNA) in the liquid-like condensates, which are induced by Pabpc1b phase separation, is required for cytoplasmic polyadenylation of shha mRNA. Intriguingly, the cytoplasmic polyadenylation regulates translation but not stability of shha mRNA, which further enhances the Shha protein level and Hh signal transduction. Taken together, our findings uncover the role of Cpeb1b-mediated cytoplasmic polyadenylation in HSPC development and provide insights into how posttranscriptional regulation can direct developmental signals with high fidelity to translate them into cell fate transition.


Assuntos
Poliadenilação , Peixe-Zebra , Animais , Peixe-Zebra/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Hedgehog/metabolismo , Hematopoese/genética
9.
Ann Neurol ; 95(6): 1069-1079, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38407506

RESUMO

OBJECTIVE: People who eat healthier diets are less likely to develop dementia, but the biological mechanism of this protection is not well understood. We tested the hypothesis that healthy diet protects against dementia because it slows the pace of biological aging. METHODS: We analyzed Framingham Offspring Cohort data. We included participants ≥60 years-old, free of dementia and having dietary, epigenetic, and follow-up data. We assessed healthy diet as long-term adherence to the Mediterranean-Dash Intervention for Neurodegenerative Delay diet (MIND, over 4 visits spanning 1991-2008). We measured the pace of aging from blood DNA methylation data collected in 2005-2008 using the DunedinPACE epigenetic clock. Incident dementia and mortality were defined using study records compiled from 2005 to 2008 visit through 2018. RESULTS: Of n = 1,644 included participants (mean age 69.6, 54% female), n = 140 developed dementia and n = 471 died over 14 years of follow-up. Greater MIND score was associated with slower DunedinPACE and reduced risks for dementia and mortality. Slower DunedinPACE was associated with reduced risks for dementia and mortality. In mediation analysis, slower DunedinPACE accounted for 27% of the diet-dementia association and 57% of the diet-mortality association. INTERPRETATION: Findings suggest that slower pace of aging mediates part of the relationship of healthy diet with reduced dementia risk. Monitoring pace of aging may inform dementia prevention. However, a large fraction of the diet-dementia association remains unexplained and may reflect direct connections between diet and brain aging that do not overlap other organ systems. Investigation of brain-specific mechanisms in well-designed mediation studies is warranted. ANN NEUROL 2024;95:1069-1079.


Assuntos
Envelhecimento , Demência , Humanos , Masculino , Feminino , Demência/epidemiologia , Demência/prevenção & controle , Idoso , Pessoa de Meia-Idade , Dieta Saudável , Estudos de Coortes , Fatores de Risco , Metilação de DNA , Idoso de 80 Anos ou mais , Dieta Mediterrânea , Estudos Longitudinais
10.
Stroke ; 55(7): 1838-1846, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38818733

RESUMO

BACKGROUND: Previous studies yielded conflicting results about the influence of blood pressure (BP) and antihypertensive treatment on cerebral small vessel disease. Here, we conducted a Mendelian randomization study to investigate the effect of BP and antihypertensive drugs on cerebral small vessel disease. METHODS: We extracted single-nucleotide polymorphisms for systolic BP and diastolic BP from a genome-wide association study (N=757 601) and screened single-nucleotide polymorphisms associated with calcium channel blockers, thiazides, angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, and ß-blockers from public resources as instrumental variables. Then, we chose the genome-wide association study of white matter hyperintensity (WMH; N=18 381), cerebral microbleed (3556 cases, 22 306 controls), white matter perivascular space (9317 cases, 29 281 controls), basal ganglia perivascular space (BGPVS; 8950 cases, 29 953 controls), hippocampal perivascular space (HIPPVS; 9163 cases, 29 708 controls), and lacunar stroke (6030 cases, 248 929 controls) as outcome data sets. Subsequently, we conducted a 2-sample Mendelian randomization analysis. RESULTS: We found that elevated systolic BP significantly increases the risk of BGPVS (odds ratio [OR], 1.05 [95% CI, 1.04-1.07]; P=1.72×10-12), HIPPVS (OR, 1.04 [95% CI, 1.02-1.05]; P=2.71×10-7), and lacunar stroke (OR, 1.41 [95% CI, 1.30-1.54]; P=4.97×10-15). There was suggestive evidence indicating that elevated systolic BP is associated with higher WMH volume (ß=0.061 [95% CI, 0.018-0.105]; P=5.58×10-3) and leads to an increased risk of cerebral microbleed (OR, 1.16 [95% CI, 1.04-1.29]; P=7.17×10-3). Elevated diastolic BP was significantly associated with higher WMH volume (ß=0.087 [95% CI, 0.049-0.124]; P=5.23×10-6) and significantly increased the risk of BGPVS (OR, 1.05 [95% CI, 1.04-1.06]; P=1.20×10-16), HIPPVS (OR, 1.03 [95% CI, 1.02-1.04]; P=2.96×10-6), and lacunar stroke (OR, 1.31 [95% CI, 1.21-1.41]; P=2.67×10-12). The use of calcium channel blocker to lower BP was significantly associated with lower WMH volume (ß=-0.287 [95% CI, -0.408 to -0.165]; P=4.05×10-6) and significantly reduced the risk of BGPVS (OR, 0.85 [95% CI, 0.81-0.89]; P=8.41×10-19) and HIPPVS (OR, 0.88 [95% CI, 0.85-0.92]; P=6.72×10-9). CONCLUSIONS: Our findings contribute to a better understanding of the pathogenesis of cerebral small vessel disease. Additionally, the utilization of calcium channel blockers to decrease BP can effectively reduce the likelihood of WMH, BGPVS, and HIPPVS. These findings offer valuable insights for the management and prevention of cerebral small vessel disease.


Assuntos
Anti-Hipertensivos , Pressão Sanguínea , Doenças de Pequenos Vasos Cerebrais , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Polimorfismo de Nucleotídeo Único , Humanos , Doenças de Pequenos Vasos Cerebrais/genética , Doenças de Pequenos Vasos Cerebrais/tratamento farmacológico , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/genética , Hipertensão/tratamento farmacológico , Hipertensão/genética , Feminino , Masculino , Acidente Vascular Cerebral Lacunar/genética , Acidente Vascular Cerebral Lacunar/tratamento farmacológico , Bloqueadores dos Canais de Cálcio/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Pessoa de Meia-Idade
11.
Small ; 20(1): e2304835, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37653619

RESUMO

Photoelectrochemical (PEC) water splitting represents an attractive strategy to realize the conversion from solar energy to hydrogen energy, but severe charge recombination in photoanodes significantly limits the conversion efficiency. Herein, a unique BiVO4 (BVO) nanobowl (NB) heterojunction photoanode, which consists of [001]-oriented BiOCl underlayer and BVO nanobowls containing embedded BiOCl nanocrystals, is fabricated by nanosphere lithography followed by in situ transformation. Experimental characterizations and theoretical simulation prove that nanobowl morphology can effectively enhance light absorption while reducing carrier diffusion path. Density functional theory (DFT) calculations show the tendency of electron transfer from BVO to BiOCl. The [001]-oriented BiOCl underlayer forms a compact type II heterojunction with the BVO, favoring electron transfer from BVO through BiOCl to the substrate. Furthermore, the embedded BiOCl nanoparticles form a bulk heterojunction to facilitate bulk electron transfer. Consequently, the dual heterojunctions engineered BVO/BiOCl NB photoanode exhibits attractive PEC performance toward water oxidation with an excellent bulk charge separation efficiency of 95.5%, and a remarkable photocurrent density of 3.38 mA cm-2 at 1.23 V versus reversible hydrogen electrode, a fourfold enhancement compared to the flat BVO counterpart. This work highlights the great potential of integrating dual heterojunctions engineering and morphology engineering in fabricating high-performance photoelectrodes toward efficient solar conversion.

12.
Plant Physiol ; 191(1): 660-678, 2023 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-36269175

RESUMO

Herbivore-associated molecular patterns (HAMPs) enable plants to recognize herbivores and may help plants adjust their defense responses. Here, we report on herbivore-induced changes in a protein disulfide isomerase (PDI) widely distributed across arthropods. PDI from the spider mite Tetranychus evansi (TePDI), a mesophyll-feeding agricultural pest worldwide, triggered immunity in multiple Solanaceae plants. TePDI-mediated cell death in Nicotiana benthamiana required the plant signaling proteins SGT1 (suppressor of the G2 allele of skp1) and HSP90 (heat shock protein 90), but was suppressed by spider mite effectors Te28 and Te84. Moreover, PDIs from phylogenetically distinct herbivorous and nonherbivorous arthropods triggered plant immunity. Finally, although PDI-induced plant defenses impaired the performance of spider mites on plants, RNAi experiments revealed that PDI genes are essential for the survival of mites and whiteflies. Our findings indicate that plants recognize evolutionarily conserved HAMPs to activate plant defense and resist pest damage, pointing to opportunities for broad-spectrum pest management.


Assuntos
Herbivoria , Tetranychidae , Animais , Isomerases de Dissulfetos de Proteínas/genética , Plantas , Nicotiana/genética , Proteínas de Plantas/genética , Tetranychidae/fisiologia
13.
J Exp Bot ; 75(5): 1493-1509, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-37952109

RESUMO

Herbivore-associated elicitors (HAEs) are active molecules produced by herbivorous insects. Recognition of HAEs by plants induces defence that resist herbivore attacks. We previously demonstrated that the tomato red spider mite Tetranychus evansi triggered defence in Nicotiana benthamiana. However, our knowledge of HAEs from T. evansi remains limited. Here, we characterize a novel HAE, Te16, from T. evansi and dissect its function in mite-plant interactions. We investigate the effects of Te16 on spider mites and plants by heterologous expression, virus-induced gene silencing assay, and RNA interference. Te16 induces cell death, reactive oxygen species (ROS) accumulation, callose deposition, and jasmonate (JA)-related responses in N. benthamiana leaves. Te16-mediated cell death requires a calcium signalling pathway, cytoplasmic localization, the plant co-receptor BAK1, and the signalling components SGT1 and HSP90. The active region of Te16-induced cell death is located at amino acids 114-293. Moreover, silencing Te16 gene in T. evansi reduces spider mite survival and hatchability, but expressing Te16 in N. benthamiana leaves enhances plant resistance to herbivores. Finally, Te16 gene is specific to Tetranychidae species and is highly conserved in activating plant immunity. Our findings reveal a novel salivary protein produced by spider mites that elicits plant defence and resistance to insects, providing valuable clues for pest management.


Assuntos
Solanum lycopersicum , Tetranychidae , Animais , Herbivoria , Tetranychidae/fisiologia , Nicotiana/genética , Solanum lycopersicum/genética , Folhas de Planta
14.
Biomacromolecules ; 25(6): 3432-3448, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38771294

RESUMO

Preventing bacterial infections is a crucial aspect of wound healing. There is an urgent need for multifunctional biomaterials without antibiotics to promote wound healing. In this study, we fabricated a guar gum (GG)-based nanocomposite hydrogel, termed GBTF, which exhibited photothermal antibacterial therapy for infected wound healing. The GBTF hydrogel formed a cross-linked network through dynamic borate/diol interactions between GG and borax, thereby exhibiting simultaneously self-healing, adaptable, and injectable properties. Additionally, tannic acid (TA)/Fe3+ nanocomplexes (NCs) were incorporated into the hydrogel to confer photothermal antibacterial properties. Under the irradiation of an 808 nm near-infrared laser, the TA/Fe3+ NCs in the hydrogel could rapidly generate heat, leading to the disruption of bacterial cell membranes and subsequent bacterial eradication. Furthermore, the hydrogels exhibited good cytocompatibility and hemocompatibility, making them a precandidate for preclinical and clinical applications. Finally, they could significantly promote bacteria-infected wound healing by reducing bacterial viability, accelerating collagen deposition, and promoting epithelial remodeling. Therefore, the multifunctional GBTF hydrogel, which was composed entirely of natural substances including guar gum, borax, and polyphenol/ferric ion NCs, showed great potential for regenerating infected skin wounds in clinical applications.


Assuntos
Antibacterianos , Galactanos , Hidrogéis , Mananas , Nanocompostos , Terapia Fototérmica , Gomas Vegetais , Cicatrização , Mananas/química , Mananas/farmacologia , Gomas Vegetais/química , Gomas Vegetais/farmacologia , Galactanos/química , Galactanos/farmacologia , Cicatrização/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Nanocompostos/química , Hidrogéis/química , Hidrogéis/farmacologia , Animais , Terapia Fototérmica/métodos , Camundongos , Taninos/química , Taninos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Humanos , Escherichia coli/efeitos dos fármacos , Boratos
15.
Skin Res Technol ; 30(7): e13774, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38953214

RESUMO

OBJECTIVE: Observational studies have identified a dual effect of circulating inflammatory proteins and immune cells on cancer progression. However, the specific mechanisms of action have not been clarified in the exacerbation of cutaneous-origin tumors. Therefore, this study aims to investigate whether the causal relationship between circulating inflammatory factors and basal cell carcinoma (BCC), cutaneous malignant melanoma (SKCM), and cutaneous squamous cell carcinoma (cSCC) is regulated by immune cells. METHODS: This study employed the Two-Sample Mendelian Randomization (TSMR) approach to investigate the causal relationships between 91 circulating inflammatory factors and three prevalent types of skin cancer from a genetic perspective. Bayesian Weighted Mendelian Randomization (BWMR) was also used to validate correlation and reverse MR to assess inverse relationships. Subsequent sensitivity analyses were conducted to limit the impact of heterogeneity and pleiotropy. Finally, the two-step Mendelian Randomization (two-step MR) method was utilized to ascertain the mediating effects of specific immune cell traits in the causal pathways linking circulating inflammatory factors with BCC, SKCM, and cSCC. RESULTS: The Inverse Variance Weighted (IVW) method and the Bayesian Weighted Algorithm collectively identified nine inflammatory factors causally associated with BCC, SKCM, and cSCC. The results from Cochran's Q test, mendelian randomization pleiotropy residual sum and outlier (MR-PRESSO), and MR-Egger intercept were not statistically significant (p < 0.05). Additionally, the proportions mediated by CD4+ CD8dim T cell %leukocyte, CD4-CD8-Natural Killer T %T cell, and CD20 on IgD-CD38-B cell for FIt3L, CCL4, and OSM were 9.26%, 8.96%, and 10.16%, respectively. CONCLUSION: Immune cell levels potentially play a role in the modulation process between circulating inflammatory proteins and cutaneous-origin exacerbated tumors. This finding offers a new perspective for the in-depth exploration of cutaneous malignancies.


Assuntos
Carcinoma Basocelular , Carcinoma de Células Escamosas , Melanoma , Análise da Randomização Mendeliana , Neoplasias Cutâneas , Humanos , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/imunologia , Melanoma/genética , Melanoma/imunologia , Melanoma/sangue , Carcinoma Basocelular/genética , Carcinoma Basocelular/imunologia , Carcinoma Basocelular/sangue , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/imunologia , Carcinoma de Células Escamosas/patologia , Teorema de Bayes , Melanoma Maligno Cutâneo
16.
Mol Cancer ; 22(1): 3, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36617554

RESUMO

BACKGROUND: This study aimed to validate whether infusion of GD2-specific fourth-generation safety-designed chimeric antigen receptor (4SCAR)-T cells is safe and whether CAR-T cells exert anti-glioblastoma (GBM) activity. METHODS: A total of eight patients with GD2-positive GBM were enrolled and infused with autologous GD2-specific 4SCAR-T cells, either through intravenous administration alone or intravenous combined with intracavitary administration. RESULTS: 4SCAR-T cells expanded for 1-3 weeks and persisted at a low frequency in peripheral blood. Of the eight evaluable patients, four showed a partial response for 3 to 24 months, three had progressive disease for 6 to 23 months, and one had stable disease for 4 months after infusion. For the entire cohort, the median overall survival was 10 months from the infusion. GD2 antigen loss and infiltrated T cells were observed in the tumor resected after infusion. CONCLUSION: Both single and combined infusions of GD2-specific 4SCAR-T cells in targeting GBM were safe and well tolerated, with no severe adverse events. In addition, GD2-specific 4SCAR-T cells partially mediate antigen loss and activate immune responses in the tumor microenvironment. Validation of our findings in a larger prospective trial is warranted. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03170141 . Registered 30 May 2017.


Assuntos
Glioblastoma , Receptores de Antígenos Quiméricos , Humanos , Glioblastoma/tratamento farmacológico , Imunoterapia Adotiva/efeitos adversos , Estudos Prospectivos , Receptores de Antígenos de Linfócitos T , Receptores de Antígenos Quiméricos/genética , Linfócitos T , Microambiente Tumoral
17.
J Hepatol ; 79(5): 1129-1138, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37459920

RESUMO

BACKGROUND & AIMS: Chronic hepatitis B is a global public health problem, and coinfection with hepatitis delta virus (HDV) worsens disease outcome. Here, we describe a hepatitis B virus (HBV) surface antigen (HBsAg)-targeting monoclonal antibody (mAb) with the potential to treat chronic hepatitis B and chronic hepatitis D. METHODS: HBsAg-specific mAbs were isolated from memory B cells of HBV vaccinated individuals. In vitro neutralization was determined against HBV and HDV enveloped with HBsAg representing eight HBV genotypes. Human liver-chimeric mice were treated twice weekly with a candidate mAb starting 3 weeks post HBV inoculation (spreading phase) or during stable HBV or HBV/HDV coinfection (chronic phase). RESULTS: From a panel of human anti-HBs mAbs, VIR-3434 was selected and engineered for pre-clinical development. VIR-3434 targets a conserved, conformational epitope within the antigenic loop of HBsAg and neutralized HBV and HDV infection with higher potency than hepatitis B immunoglobulins in vitro. Neutralization was pan-genotypic against strains representative of HBV genotypes A-H. In the spreading phase of HBV infection in human liver-chimeric mice, a parental mAb of VIR-3434 (HBC34) prevented HBV dissemination and the increase in intrahepatic HBV RNA and covalently closed circular DNA. In the chronic phase of HBV infection or co-infection with HDV, HBC34 treatment decreased circulating HBsAg by >1 log and HDV RNA by >2 logs. CONCLUSIONS: The potently neutralizing anti-HBs mAb VIR-3434 reduces circulating HBsAg and HBV/HDV viremia in human liver-chimeric mice. VIR-3434 is currently in clinical development for treatment of patients with chronic hepatitis B or D. IMPACT AND IMPLICATIONS: Chronic infection with hepatitis B virus and co-infection with hepatitis D virus place approximately 290 million individuals worldwide at risk of severe liver disease and cancer. Available treatments result in low rates of functional cure or require lifelong therapy that does not eliminate the risk of liver disease. We isolated and characterized a potent human antibody that neutralizes hepatitis B and D viruses and reduces infection in a mouse model. This antibody could provide a new treatment for patients with chronic hepatitis B and D.

18.
J Urban Health ; 100(5): 1007-1023, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37594675

RESUMO

Compared to previous studies commonly using a single summary score, we aimed to construct a multidomain neighborhood environmental vulnerability index (NEVI) to characterize the magnitude and variability of area-level factors with the potential to modify the association between environmental pollutants and health effects. Using the Toxicological Prioritization Index framework and data from the 2015-2019 U.S. Census American Community Survey and the 2020 CDC PLACES Project, we quantified census tract-level vulnerability overall and in 4 primary domains (demographic, economic, residential, and health status), 24 subdomains, and 54 distinct area-level features for New York City (NYC). Overall and domain-specific indices were calculated by summing standardized feature values within the subdomains and then aggregating and weighting based on the number of features within each subdomain within equally-weighted primary domains. In citywide comparisons, NEVI was correlated with multiple existing indices, including the Neighborhood Deprivation Index (r = 0.91) and Social Vulnerability Index (r = 0.87) but provided additional information on features contributing to vulnerability. Vulnerability varied spatially across NYC, and hierarchical cluster analysis using subdomain scores revealed six patterns of vulnerability across domains: 1) low in all, 2) primarily low except residential, 3) medium in all, 4) high demographic, economic, and residential 5) high economic, residential, and health status, and 6) high demographic, economic and health status. Created using methods that offer flexibility for theory-based construction, NEVI provided detailed vulnerability metrics across domains that can inform targeted research and public health interventions aimed at reducing the health impacts from environmental exposures across urban centers.


Assuntos
Exposição Ambiental , Nevo , Humanos , Cidade de Nova Iorque , Nível de Saúde , Saúde Pública
19.
BMC Cardiovasc Disord ; 23(1): 410, 2023 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-37596540

RESUMO

BACKGROUND: Allicin is a bioactive compound with potent antioxidative activity and plays a protective effect in myocardial damage and fibrosis. The role and mechanism of Allicin in septic cardiomyopathy are unclear. In this study, we investigated the effects and underlying mechanisms of Allicin on lipopolysaccharide (LPS) induced injury in H9c2 cardiomyocytes. METHODS: H9c2 cardiomyocyte cells were pretreated with Allicin (0, 25, 50, and 100 µM) for 2 h, followed by incubation with LPS (10 µg/mL) for 24 h at 37 °C. Cell viability (cell counting kit-8 [CCK-8]), apoptosis (TUNEL staining), oxidative stress (malondialdehyde [MDA] and superoxide dismutase [SOD]), and cytokines release (Interleukin beta [IL-ß], Interleukin 6 [IL-6], and tumor necrosis factor-alpha [TNF-α]) were determined. The mRNA and protein expression of nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), and NLR family pyrin domain containing 3 (NLRP3) signaling pathway molecules were quantified by real-time quantitative PCR (RT-qPCR) and western blot, respectively. RESULTS: Allicin had no effect on H9c2 cell viability but attenuated LPS-induced injury, with increased cell viability, reduction in inflammatory cytokines release, apoptosis, reduced MDA, and increased SOD (P < 0.05). Additionally, Allicin increased Nrf2 and cellular HO-1 expressions in LPS-treated H9c2 cells. Moreover, Allicin modulated the NLRP3 inflammasome, increased the cleaved caspase-1 (p10) protein, and attenuated the LPS-induced increase in NLRP3, pro-IL-1ß, and IL-1ß proteins. Silencing of Nrf2 by siRNA (siNrf2) significantly attenuated Allicin-induced increase in cell viability and HO-1 and decrease in NLRP3 protein in LPS-stimulated H9c2 cells. CONCLUSIONS: Allicin protects cardiomyocytes against LPS­induced injury through activation of Nrf2/HO-1 and inhibition of NLRP3 signaling pathways.


Assuntos
Lipopolissacarídeos , Miócitos Cardíacos , Humanos , Lipopolissacarídeos/toxicidade , Fator 2 Relacionado a NF-E2/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Heme Oxigenase-1 , Citocinas , Interleucina-6
20.
BMC Pregnancy Childbirth ; 23(1): 508, 2023 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-37434137

RESUMO

BACKGROUND: Placenta accreta spectrum (PAS) disorder is a major cause of postpartum hemorrhage-associated maternal and fetal death, and novel methods for PAS screening are urgently needed for clinical application. METHODS: The purpose of this study was to develop new methods for PAS screening using serum biomarkers and clinical indicators. A total of 95 PAS cases and 137 controls were enrolled in a case-control study as cohort one, and 44 PAS cases and 35 controls in a prospective nested case-control study were enrolled as cohort two. All subjects were pregnant women of Chinese Han population. Biomarkers for PAS from maternal blood samples were screened based on high-throughput immunoassay and were further validated in three phases of cohort one. Screening models for PAS were generated using maternal serum biomarkers and clinical indicators, and were validated in two cohorts. The expression levels of biomarkers were analyzed using histopathological and immunohistochemical (IHC) techniques, and gene expression was examined by QPCR in the human placenta. Binary logistic regression models were built, and the area under the curve (AUC), sensitivity, specificity, and Youden index were calculated. Statistical analyses and model building were performed in SPSS and graphs were generated in GraphPad Prism. The independent-sample t test was used to compare numerical data between two groups. For nonparametric variables, a Mann-Whitney U test or a X2 test was used. RESULTS: The results demonstrated that the serum levels of matrix metalloproteinase-1 (MMP-1), epidermal growth factor (EGF), and vascular endothelial growth factor-A (VEGF-A) were consistently higher, while the level of tissue-type plasminogen activator (tPA) was significantly lower in PAS patients compared with normal term controls and patients with pre-eclampsia (PE) and placenta previa (PP). IHC and QPCR analysis confirmed that the expression of the identified biomarkers significantly changed during the third trimester in human placenta. The generated screening model combining serum biomarkers and clinical indicators detected 87% of PAS cases with AUC of 0.94. CONCLUSIONS: Serum biomarkers can be used for PAS screening with low expense and high clinical performance; therefore, it may help to develop a practicable method for clinical prenatal PAS screening.


Assuntos
Placenta Acreta , Feminino , Humanos , Gravidez , Biomarcadores/sangue , Estudos de Casos e Controles , Placenta Acreta/diagnóstico , Estudos Prospectivos , Fator A de Crescimento do Endotélio Vascular
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