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1.
NPJ Vaccines ; 9(1): 72, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38575581

RESUMO

Varicella zoster virus (VZV) is a highly contagious human herpes virus responsible for causing chickenpox (varicella) and shingles (herpes zoster). Despite the approval of a highly effective vaccine, Shingrix®, the global incidence of herpes zoster is increasing and the economic burden to the health care system and society are substantial due to significant loss of productivity and health complications, particularly among elderly and immunocompromised individuals. This is primarily because access to the vaccines remains mostly limited to countries within developed economies, such as USA and Canada. Therefore, similarly effective vaccines against VZV that are more accessible to the rest-of-the-world are necessary. In this study, we aimed to evaluate immunogenicity and memory response induced by three mRNA-LNP-based vaccine candidates targeting VZV's surface glycoprotein E (gE). C57BL/6 mice were immunized with each candidate vaccine, and humoral and cellular immune responses were assessed. Our results demonstrate that the mRNA-LNP-based vaccine candidates elicited robust and durable humoral responses specific to the gE antigen. Notably, mice vaccinated with the mRNA-LNP vaccines exhibited significantly higher antigen-specific T-cell cytokine production compared to the group receiving Shingrix®, the current standard of care vaccine. Additionally, mRNA-LNP vaccines induced long-lasting memory response, as evidenced by detection of persistent gE-specific Long-Lived Plasma Cells (LLPCs) and memory T cells four months after final immunization. These findings underscore the potential of our mRNA-LNP-based vaccine candidates in generating potent immune responses against VZV, offering promising prospects for their clinical development as an effective prophylactic vaccine against herpes zoster.

2.
Curr Med Imaging ; 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38343050

RESUMO

OBJECTIVE: To investigate the influence of improved exposure parameters on the image quality of multi-slice spiral computed tomography in nasal bone fracture imaging. METHODS: Fifty patients with optimised parameters combined with coronal scanning were allocated to the modified group and 50 patients with routine scanning parameters to the routine group. The image quality and nasal bone display of the two groups were assessed and statistically analysed, and the quality of scanned images before and after parameter optimisation was compared. RESULTS: The optimised image quality was better than that of conventional scanning parameters. The parameters used were 120 kv, 180 mA, a layer thickness of 0.625 mm, a layer spacing of 0.312 mm, a pitch of 0.516:1, a frame speed of 1 s, a scanning field of 12 cm and a reconstructed layer thickness for scanning of 0.625 mm; the scanned image was clear, and the parameter optimisation was achieved. This ensures that the annotation data in ITK labelling is more accurate. CONCLUSION: The optimised parameters and scanned coronal plane show the nasal bone and its surrounding structures more comprehensively, which is of high diagnostic value for nasal bone fractures. The three-dimensional annotation data based on ITK is more standardised, laying a foundation for the subsequent research of artificial intelligence modelling.

3.
Eur J Pharmacol ; 968: 176388, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38367685

RESUMO

Researches have proposed that obesity might contribute to development of oligoasthenospermia. This study was performed to confirm whether obesity contributes to oligoasthenospermia as well as the underlying mechanisms in mice fed with a high fat diet (HFD). Meanwhile, the actions of metformin, a drug of well-known weight-lowering effect, on sperm quality in obese mice were investigated. Our results showed that HFD feeding reduced sperm quality and steroid hormone levels in mice, associated with disruptions in testicular histomorphology and spermatogenesis. Moreover, obesity increased sperm apoptosis. These effects could be prevented by metformin treatment in HFD-fed mice. Mechanistically, an increasement in lipid contents associated with decreased hormone-sensitive lipase (HSL) protein expression in testes in HFD-fed mice was observed, which could be improved by metformin treatment. Then, the model of TM4 mouse Sertoli cells stimulated with palmitic acid (PA) was used to investigate the potential effect of lipid retention on testicular apoptosis and sperm quality reduction. In consistent, PA exposure elevated lipid contents as well as apoptosis in TM4 cells, which could also be improved by metformin treatment. Of note, the protein expression of HSL was reduced stimulated by PA in TM4 cells, also rescued by metformin. Then, anti-apoptosis effect of metformin would be lost with the deficiency of HSL. In summary, our study propose that obesity contributes to oligoasthenospermia by increasing sperm apoptosis induced by impaired lipid hydrolysis due to HSL down-regulation, which could be prevented with metformin treatment via regulating the expression of HSL in testis in mice.


Assuntos
Metformina , Testículo , Masculino , Camundongos , Animais , Esterol Esterase/metabolismo , Metformina/farmacologia , Metformina/uso terapêutico , Sêmen/metabolismo , Obesidade/complicações , Obesidade/tratamento farmacológico , Obesidade/metabolismo , Dieta Hiperlipídica/efeitos adversos , Ácido Palmítico/farmacologia
4.
Allergy Asthma Immunol Res ; 15(5): 603-613, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37827979

RESUMO

PURPOSE: Allergic rhinitis (AR) is a T helper type 2 (Th2)-mediated inflammatory disease. The E3 ligase tripartite motif-containing 24 (TRIM24) regulates the recruitment of acetyltransferase CREB-binding protein (CBP) to signal transducer and activator of transcription 6 (STAT6). CBP mediates the acetylation of STAT6 and decreases its activity. To date, the precise role of TRIM24 in AR has not been fully interpreted. Herein, our study aimed to explore the functions of TRIM24 in AR. METHODS: The expression of TRIM24 in peripheral blood mononuclear cells (PBMCs) and CD4+ T cells from patients with AR was measured. TRIM24-conditional knockout mice with TRIM24 deficiency in CD4+ T cells were generated. Wide-type (WT) AR mice and TRIM24-conditional knockout AR mice were established. Then, AR symptoms and interleukin (IL)-4 levels were compared. Further, the proliferation, activation and polarization of CD4+ T cells from WT mice and TRIM24 knockout mice after stimulation were determined. The effects of TRIM24 deficiency on STAT6 activities were also evaluated. RESULTS: Downregulated TRIM24 expression was detected in PBMCs and CD4+ T cells from patients with AR. TRIM24 conditional knockout mice had more sever AR symptoms with elevated IL-4 production. TRIM24-knockout CD4+ T cells had similar proliferation and activation when compared to WT CD4+ T cells, while they had enhanced Th2 polarization. TRIM24-knockout CD4+ T cells had decreased acetylation of STAT6 and enhanced STAT6 activities after IL-4 stimulation. The regulation of STAT6 activities by TRIM24 depended on TRIM24 N terminal RIGN domain and Lys383 acetylation site of STAT6. CONCLUSIONS: TRIM24 suppresses Th2-mediated AR by regulating the acetylation of STAT6.

5.
Front Neurosci ; 17: 1173127, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37065908

RESUMO

This study aimed to investigate the eye movement characteristics and visual fatigue of virtual reality games with different interaction modes. Eye movement data were recorded using the built-in eye tracker of the VR device and eye movement parameters were calculated from the recorded raw data. The Visual Fatigue Scales and Simulator Sickness Questionnaire were used to subjectively assess visual fatigue and overall discomfort of the VR experience. Sixteen male and 17 female students were recruited for this study. Results showed that both the primary and 360 mode of VR could cause visual fatigue after 30 min of gameplay, with significant differences observed in eye movement behavior between the two modes. The primary mode was more likely to cause visual fatigue, as shown by objective measurements of blinking and pupil diameter. Fixation and saccade parameters also showed significant differences between the two modes, possibly due to the different interaction modes employed in the 360 mode. Further research is required to examine the effects of different content and interactive modes of VR on visual fatigue, as well as to develop more objective measures for assessing it.

6.
JCI Insight ; 8(8)2023 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-36853802

RESUMO

Sosuga virus (SOSV) is a recently discovered paramyxovirus with a single known human case of disease. There has been little laboratory research on SOSV pathogenesis or immunity, and no approved therapeutics or vaccines are available. Here, we report the discovery of human mAbs from the circulating memory B cells of the only known human case and survivor of SOSV infection. We isolated 6 mAbs recognizing the functional attachment protein hemagglutinin-neuraminidase (HN) and 18 mAbs against the fusion (F) protein. The anti-HN mAbs all targeted the globular head of the HN protein and could be organized into 4 competition-binding groups that exhibited epitope diversity. The anti-F mAbs can be divided into pre- or postfusion conformation-specific categories and further into 8 competition-binding groups. The only Ab in the panel that did not display neutralization activity was the single postfusion-specific anti-F mAb. Most of the anti-HN mAbs were more potently neutralizing than the anti-F mAbs, with mAbs in 1 of the HN competition-binding groups possessing ultrapotent (<1 ng/mL) half-maximal inhibitory virus neutralization values. These findings provide insight into the molecular basis for human Ab recognition of paramyxovirus surface proteins and the mechanisms of SOSV neutralization.


Assuntos
Anticorpos Monoclonais , Paramyxoviridae , Humanos , Proteínas Virais
7.
Bioengineering (Basel) ; 9(7)2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35877355

RESUMO

The monitoring of intracranial pressure (ICP) is essential for the detection and treatment of most craniocerebral diseases. Invasive methods are the most accurate approach to measure ICP; however, these methods are prone to complications and have a limited range of applications. Therefore, non-invasive ICP measurement is preferable in a range of scenarios. The current non-invasive ICP measurement methods comprise fluid dynamics, and ophthalmic, otic, electrophysiological, and other methods. This article reviews eight methods of non-invasive estimation of ICP from ocular measurements, namely optic nerve sheath diameter, flash visual evoked potentials, two-depth transorbital Doppler ultrasonography, central retinal venous pressure, optical coherence tomography, pupillometry, intraocular pressure measurement, and retinal arteriole and venule diameter ratio. We evaluated and presented the indications and main advantages and disadvantages of these methods. Although these methods cannot completely replace invasive measurement, for some specific situations and patients, non-invasive measurement of ICP still has great potential.

8.
J Oncol ; 2022: 6160539, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35571493

RESUMO

Background: Cytoplasmic activation/proliferation-associated protein-1 (CAPRIN1) plays an important role in carcinogenesis, whereas its role in laryngeal squamous cell carcinoma remains unclear. This study was designed to investigate the roles of CAPRIN1 in glycolysis and chemoresistance and its underlying mechanisms in laryngeal squamous cell carcinoma. Methods: Cell viability was evaluated by using CCK-8 and colony formation assays. qRT-PCR, Western blotting, and immunohistochemistry were used to determine the expressions of target genes. Gene knockdown and overexpression cell lines were constructed by performing transfection of siRNAs and plasmids, respectively. Luciferase reporter assay, RNA pull-down, and RNA immunoprecipitation assays were applied to evaluate the RNA-protein interactions. The Kaplan-Meier analysis was performed to evaluate the relationship between gene expression and overall survival rate. Results: An elevation of CAPRIN1 was identified to be associated with chemoresistance and poor prognosis in patients with laryngeal cancer. The increase of CAPRIN1 promoted glycolysis and chemoresistance, whereas the knockdown of CAPRIN1 inhibited glycolysis and chemoresistance in laryngeal cancer cells. The underlying mechanistic investigation revealed that CAPRIN1 promoted glycolysis and chemoresistance of laryngeal cancer cells by the regulation of Zic Family Member 5 (ZIC5). Conclusion: CAPRIN1 promoted laryngeal squamous cell carcinoma glycolysis and chemoresistance by the regulation of ZIC5.

9.
PLoS Pathog ; 18(5): e1010518, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35584193

RESUMO

The three human pathogenic ebolaviruses: Zaire (EBOV), Bundibugyo (BDBV), and Sudan (SUDV) virus, cause severe disease with high fatality rates. Epitopes of ebolavirus glycoprotein (GP) recognized by antibodies with binding breadth for all three ebolaviruses are of major interest for rational vaccine design. In particular, the heptad repeat 2 -membrane-proximal external region (HR2-MPER) epitope is relatively conserved between EBOV, BDBV, and SUDV GP and targeted by human broadly-neutralizing antibodies. To study whether this epitope can serve as an immunogen for the elicitation of broadly-reactive antibody responses, protein design in Rosetta was employed to transplant the HR2-MPER epitope identified from a co-crystal structure with the known broadly-reactive monoclonal antibody (mAb) BDBV223 onto smaller scaffold proteins. From computational analysis, selected immunogen designs were produced as recombinant proteins and functionally validated, leading to the identification of a sterile alpha motif (SAM) domain displaying the BDBV-HR2-MPER epitope near its C terminus as a promising candidate. The immunogen was fused to one component of a self-assembling, two-component nanoparticle and tested for immunogenicity in rabbits. Robust titers of cross-reactive serum antibodies to BDBV and EBOV GPs and moderate titers to SUDV GP were induced following immunization. To confirm the structural composition of the immunogens, solution NMR studies were conducted and revealed structural flexibility in the C-terminal residues of the epitope. Overall, our study represents the first report on an epitope-focused immunogen design based on the structurally challenging BDBV-HR2-MPER epitope.


Assuntos
Ebolavirus , Doença pelo Vírus Ebola , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais , Epitopos , Glicoproteínas , Coelhos
10.
Autoimmunity ; 55(2): 118-126, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35007167

RESUMO

This study was designed to evaluate the effects of BoxA on allergic rhinitis (AR). Ovalbumin (OVA)-induced AR mice model was employed and BoxA was administered to AR mice. AR symptoms, levels of cytokines and chemokines, and the expression of high mobility group box 1 (HMGB1), TLR2, and TLR4 were measured. BoxA treatment significantly ameliorated AR symptoms, decreased level of histamine, OVA-specific antibodies, suppressed the infiltration of immune cells in nasal tissues, inhibited the expression of IL-4, IL-6, IL-5, TNF-α, IL-13, IL-17, IL-2 while promoting the expression of IL-10, suppressed the expression of HMGB1, TLR2, and TLR4 in AR mice. BoxA ameliorated allergic rhinitis in mice by inhibiting HMGB1.


Assuntos
Proteína HMGB1/metabolismo , Rinite Alérgica , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina , Rinite Alérgica/tratamento farmacológico
11.
Nat Microbiol ; 6(10): 1233-1244, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34548634

RESUMO

Understanding the molecular basis for immune recognition of SARS-CoV-2 spike glycoprotein antigenic sites will inform the development of improved therapeutics. We determined the structures of two human monoclonal antibodies-AZD8895 and AZD1061-which form the basis of the investigational antibody cocktail AZD7442, in complex with the receptor-binding domain (RBD) of SARS-CoV-2 to define the genetic and structural basis of neutralization. AZD8895 forms an 'aromatic cage' at the heavy/light chain interface using germ line-encoded residues in complementarity-determining regions (CDRs) 2 and 3 of the heavy chain and CDRs 1 and 3 of the light chain. These structural features explain why highly similar antibodies (public clonotypes) have been isolated from multiple individuals. AZD1061 has an unusually long LCDR1; the HCDR3 makes interactions with the opposite face of the RBD from that of AZD8895. Using deep mutational scanning and neutralization escape selection experiments, we comprehensively mapped the crucial binding residues of both antibodies and identified positions of concern with regards to virus escape from antibody-mediated neutralization. Both AZD8895 and AZD1061 have strong neutralizing activity against SARS-CoV-2 and variants of concern with antigenic substitutions in the RBD. We conclude that germ line-encoded antibody features enable recognition of the SARS-CoV-2 spike RBD and demonstrate the utility of the cocktail AZD7442 in neutralizing emerging variant viruses.


Assuntos
Anticorpos Neutralizantes/química , Anticorpos Neutralizantes/genética , SARS-CoV-2/imunologia , Anticorpos Monoclonais/química , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/química , Anticorpos Antivirais/genética , Anticorpos Antivirais/imunologia , Variação Antigênica , Sítios de Ligação , COVID-19/imunologia , COVID-19/virologia , Regiões Determinantes de Complementaridade/química , Regiões Determinantes de Complementaridade/genética , Humanos , Mutação , Domínios Proteicos , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia
12.
Cell Rep ; 36(9): 109628, 2021 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-34469726

RESUMO

Hendra virus and Nipah virus (NiV), members of the Henipavirus (HNV) genus, are zoonotic paramyxoviruses known to cause severe disease across six mammalian orders, including humans. We isolated a panel of human monoclonal antibodies (mAbs) from the B cells of an individual with prior exposure to equine Hendra virus (HeV) vaccine, targeting distinct antigenic sites. The most potent class of cross-reactive antibodies achieves neutralization by blocking viral attachment to the host cell receptors ephrin-B2 and ephrin-B3, with a second class being enhanced by receptor binding. mAbs from both classes display synergistic activity in vitro. In a stringent hamster model of NiV Bangladesh (NiVB) infection, antibodies from both classes reduce morbidity and mortality and achieve synergistic protection in combination. These candidate mAbs might be suitable for use in a cocktail therapeutic approach to achieve synergistic potency and reduce the risk of virus escape.


Assuntos
Anticorpos Monoclonais/farmacologia , Anticorpos Neutralizantes/farmacologia , Antivirais/farmacologia , Efrina-B2/antagonistas & inibidores , Efrina-B3/antagonistas & inibidores , Infecções por Henipavirus/prevenção & controle , Henipavirus/patogenicidade , Receptores Virais/antagonistas & inibidores , Animais , Especificidade de Anticorpos , Chlorocebus aethiops , Reações Cruzadas , Modelos Animais de Doenças , Quimioterapia Combinada , Efrina-B2/imunologia , Efrina-B2/metabolismo , Efrina-B3/imunologia , Efrina-B3/metabolismo , Feminino , Infecções por Henipavirus/imunologia , Infecções por Henipavirus/metabolismo , Infecções por Henipavirus/virologia , Interações Hospedeiro-Patógeno , Humanos , Mesocricetus , Receptores Virais/imunologia , Receptores Virais/metabolismo , Células Vero
13.
J Clin Invest ; 131(15)2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-34156974

RESUMO

Broadly reactive antibodies targeting the influenza A virus hemagglutinin (HA) head domain are thought to be rare and to require extensive somatic mutations or unusual structural features to achieve breadth against divergent HA subtypes. Here we describe common genetic and structural features of protective human antibodies from several individuals recognizing the trimer interface (TI) of the influenza A HA head, a recently identified site of vulnerability. We examined the sequence of TI-reactive antibodies, determined crystal structures for TI antibody-antigen complexes, and analyzed the contact residues of the antibodies on HA to discover common genetic and structural features of TI antibodies. Our data reveal that many TI antibodies are encoded by a light chain variable gene segment incorporating a shared somatic mutation. In addition, these antibodies have a shared acidic residue in the heavy chain despite originating from diverse heavy chain variable gene segments. These studies show that the TI region of influenza A HA is a major antigenic site with conserved structural features that are recognized by a common human B cell public clonotype. The canonical nature of this antibody-antigen interaction suggests that the TI epitope might serve as an important target for structure-based vaccine design.


Assuntos
Anticorpos Neutralizantes/química , Anticorpos Antivirais/química , Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Vírus da Influenza A Subtipo H1N1/química , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Epitopos/química , Epitopos/imunologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Humanos , Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/química , Vacinas contra Influenza/imunologia
14.
Immunopharmacol Immunotoxicol ; 43(3): 319-327, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33900898

RESUMO

OBJECTIVE: Luteolin has an anti-allergic effect but its mechanism is not clear. This study attempted to determine the mechanisms of luteolin in rhinitis. METHODS: Allergic rhinitis rat model was established by ovalbumin (OVA) stimulation. Then, the rats were treated with normal saline, luteolin, or lipopolysaccharide (LPS) for 14 days. Nasal symptoms were scored; the histopathological changes of nasal mucosa were detected by hematoxylin-eosin staining. Serum levels of Th1 type cytokines (IFN-γ, IL-2), Th2 type cytokines (IL-4, IL-5, IL-13), and OVA-specific IgE (sIgE) were determined by ELISA. The expressions of Toll-like receptor 4 (TLR4) and p65 in nasal mucosa were detected by Western blot or immunohistochemistry. RESULTS: Luteolin decreased symptom scores, specifically, the scores in control group, model group, model + 0.1 mg/kg luteolin, model + 1 mg/kg luteolin, and model + 10 mg/kg luteolin groups were 0.63 ± 0.52, 7.88 ± 0.83, 1.38 ± 0.52, 2.75 ± 0.46, and 5.00 ± 0.53, respectively. Luteolin ameliorated nasal mucosa inflammation by promoting the down-regulated levels of Th1 type cytokines, and suppressing the up-regulated levels of Th2 type cytokines, OVE-sIgE, TLR4, and p65. LPS further increased symptom scores, aggravated nasal mucosa inflammation, improved the unbalance of Th1/Th2 type cytokines, and lowered the expressions of OVE-sIgE, TLR4, and p65. Moreover, LPS reversed the effect of luteolin on allergic rhinitis rats. CONCLUSION: Luteolin ameliorated inflammation and Th1/Th2 imbalance via regulating the TLR4/NF-κB pathway in allergic rhinitis rats. This study provided novel evidence that luteolin could be used as a candidate drug in allergic rhinitis treatment.


Assuntos
Luteolina/farmacologia , NF-kappa B/imunologia , Rinite Alérgica/imunologia , Transdução de Sinais/efeitos dos fármacos , Células Th1/imunologia , Células Th2/imunologia , Receptor 4 Toll-Like/imunologia , Animais , Feminino , Ratos , Ratos Sprague-Dawley , Rinite Alérgica/tratamento farmacológico , Rinite Alérgica/patologia , Transdução de Sinais/imunologia , Células Th1/patologia , Células Th2/patologia
15.
bioRxiv ; 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33532768

RESUMO

The SARS-CoV-2 pandemic has led to an urgent need to understand the molecular basis for immune recognition of SARS-CoV-2 spike (S) glycoprotein antigenic sites. To define the genetic and structural basis for SARS-CoV-2 neutralization, we determined the structures of two human monoclonal antibodies COV2-2196 and COV2-21301, which form the basis of the investigational antibody cocktail AZD7442, in complex with the receptor binding domain (RBD) of SARS-CoV-2. COV2-2196 forms an 'aromatic cage' at the heavy/light chain interface using germline-encoded residues in complementarity determining regions (CDRs) 2 and 3 of the heavy chain and CDRs 1 and 3 of the light chain. These structural features explain why highly similar antibodies (public clonotypes) have been isolated from multiple individuals1-4. The structure of COV2-2130 reveals that an unusually long LCDR1 and HCDR3 make interactions with the opposite face of the RBD from that of COV2-2196. Using deep mutational scanning and neutralization escape selection experiments, we comprehensively mapped the critical residues of both antibodies and identified positions of concern for possible viral escape. Nonetheless, both COV2-2196 and COV2130 showed strong neutralizing activity against SARS-CoV-2 strain with recent variations of concern including E484K, N501Y, and D614G substitutions. These studies reveal germline-encoded antibody features enabling recognition of the RBD and demonstrate the activity of a cocktail like AZD7442 in preventing escape from emerging variant viruses.

16.
Cell ; 183(6): 1536-1550.e17, 2020 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-33306954

RESUMO

Hendra (HeV) and Nipah (NiV) viruses are emerging zoonotic pathogens in the Henipavirus genus causing outbreaks of disease with very high case fatality rates. Here, we report the first naturally occurring human monoclonal antibodies (mAbs) against HeV receptor binding protein (RBP). All isolated mAbs neutralized HeV, and some also neutralized NiV. Epitope binning experiments identified five major antigenic sites on HeV-RBP. Animal studies demonstrated that the most potent cross-reactive neutralizing mAbs, HENV-26 and HENV-32, protected ferrets in lethal models of infection with NiV Bangladesh 3 days after exposure. We solved the crystal structures of mAb HENV-26 in complex with both HeV-RBP and NiV-RBP and of mAb HENV-32 in complex with HeV-RBP. The studies reveal diverse sites of vulnerability on RBP recognized by potent human mAbs that inhibit virus by multiple mechanisms. These studies identify promising prophylactic antibodies and define protective epitopes that can be used in rational vaccine design.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Vírus Hendra/imunologia , Henipavirus/imunologia , Testes de Neutralização , Vírus Nipah/imunologia , Receptores Virais/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/química , Anticorpos Monoclonais/isolamento & purificação , Antígenos Virais/imunologia , Sítios de Ligação , Ligação Competitiva , Encéfalo/patologia , Quirópteros/virologia , Reações Cruzadas/imunologia , Cristalografia por Raios X , Efrina-B2/metabolismo , Feminino , Furões/virologia , Humanos , Interferometria , Fígado/patologia , Modelos Moleculares , Ligação Proteica , Conformação Proteica , Domínios Proteicos , Receptores Virais/química , Receptores Virais/metabolismo
17.
J Clin Invest ; 130(9): 4734-4739, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32749241

RESUMO

Although broadly protective, stem-targeted Abs against the influenza A virus hemagglutinin (HA) have been well studied, very limited information is available on Abs that broadly recognize the head domain. We determined the crystal structure of the HA protein of the avian H7N9 influenza virus in complex with a pan-H7, non-neutralizing, protective human Ab. The structure revealed a B cell epitope in the HA head domain trimer interface (TI). This discovery of a second major protective TI epitope supports a model in which uncleaved HA trimers exist on the surface of infected cells in a highly dynamic state that exposes hidden HA head domain features.


Assuntos
Anticorpos Monoclonais/química , Anticorpos Neutralizantes/química , Anticorpos Antivirais/química , Epitopos de Linfócito B/química , Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Vírus da Influenza A Subtipo H7N1/química , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Epitopos de Linfócito B/imunologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Humanos , Vírus da Influenza A Subtipo H7N1/imunologia , Camundongos , Domínios Proteicos , Multimerização Proteica
18.
Structure ; 28(10): 1124-1130.e5, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-32783953

RESUMO

The amount of antibody (Ab) variable gene sequence information is expanding rapidly, but our ability to predict the function of Abs from sequence alone is limited. Here, we describe a sequence-to-function prediction method that couples structural data for a single Ab/antigen (Ag) complex with repertoire data. We used a position-specific structure-scoring matrix (P3SM) incorporating structure-prediction scores from Rosetta to identify Ab variable loops that have predicted structural similarity to the influenza virus-specific human Ab CH65. The P3SM approach identified new members of this Ab class. Recombinant Ab expression, crystallography, and virus inhibition assays showed that the HCDR3 loops of the newly identified Abs possessed similar structure and antiviral activity as the comparator CH65. This approach enables discovery of new human Abs with desired structure and function using cDNA repertoires that are obtained readily with current amplicon sequencing techniques.


Assuntos
Anticorpos/química , Regiões Determinantes de Complementaridade/química , Epitopos/metabolismo , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Anticorpos/genética , Anticorpos/metabolismo , Anticorpos Antivirais/química , Anticorpos Antivirais/metabolismo , Cristalografia por Raios X , Bases de Dados Factuais , Glicoproteínas de Hemaglutininação de Vírus da Influenza/metabolismo , Humanos , Fragmentos Fab das Imunoglobulinas/química , Fragmentos Fab das Imunoglobulinas/genética , Fragmentos Fab das Imunoglobulinas/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Homologia de Sequência de Aminoácidos , Homologia Estrutural de Proteína
19.
PLoS One ; 15(7): e0236387, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32697812

RESUMO

Population migration and urban traffic are two important aspects of the socioeconomic system. We analyze the trends of social production and resumption of life after the coronavirus disease 2019 (COVID-19)-influenced Spring Festival in 2020 with statistics on reported cases of COVID-19 from China's National Health Commission and big data from Baidu Migration (a platform collecting population migration data). We find that (1) the distribution of COVID-19 cases throughout mainland China has a specific spatial pattern. Provinces in eastern China have more reported cases than those in western China, and provinces adjacent to Hubei have more confirmed COVID-19 cases than nonadjacent provinces. Densely populated regions with well-developed economies and transportation are more likely to have cluster infection incidents. (2) The COVID-19 epidemic severely impacts the return of the migrant population in the Spring Festival travel rush, as demonstrated by the significant reduction in the return scale, along with the extended timespan and uncertainty regarding the end of the travel rush. Among 33 provinces, special administrative regions, autonomous regions and municipalities, 23 of them (approximately 70%) have a return rate below 60%. Hubei, Hong Kong, Xinjiang, and Inner Mongolia have the lowest return rates (below 5%), whereas the return rates in Hainan and Shandong, 272.72% and 97.35%, respectively, indicate the best trend of resumption. Due to government regulations, the population return in densely populated and well-developed regions shows a positive trend. (3) The resumption of urban traffic is slow and varies greatly in different regions. The urban traffic conditions in 22 provinces and municipalities have a more than 60% level of resumption. Guizhou and Yunnan have the highest level of resumption of urban traffic, whereas Xinjiang, Hubei, and Heilongjiang have the lowest (29.37%, 35.76%, and 37.90%, respectively). However, provinces and municipalities with well-developed intercity traffic have a lower level of resumption, mainly because of regulatory methods such as lockdowns and traffic restrictions. The increased public awareness of epidemic prevention and the decreased frequency of outdoor activities are also two positive factors slowing the spread of the epidemic. (4) Time will be necessary to fully resume social production and life throughout China. Xining and Jinan have the highest levels of resumption, 82.14% and 71.51%, respectively. Urumqi and Wuhan are the cities with the lowest levels of resumption, only 0.11% and 0.61%, respectively. Currently, 12 of 33 provinces and municipalities have levels of resumption of more than 80%; among them, Guizhou, Yunnan, and Gansu have with the highest levels of resumption and have nearly resumed the 2019 levels of work and life, whereas Xinjiang and Hubei have the lowest resumption rates, only 0.09% and 7.57%, respectively. Thus, relevant government departments should focus more on densely populated and well-developed provinces and cities when applying epidemic prevention and work resumption methods. We reveal the general conditions of the epidemic and the population return scale across China, along with urban traffic conditions and the resumption of social production and life under COVID-19, providing a scientific basis for local governments to make further decisions on work resumption.


Assuntos
Infecções por Coronavirus/epidemiologia , Pneumonia Viral/epidemiologia , Viagem/estatística & dados numéricos , Condução de Veículo , Betacoronavirus , COVID-19 , China/epidemiologia , Cidades , Atividades Humanas/estatística & dados numéricos , Humanos , Pandemias , SARS-CoV-2 , Análise Espaço-Temporal
20.
Exp Biol Med (Maywood) ; 245(14): 1222-1232, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32536202

RESUMO

IMPACT STATEMENT: This work expanded the knowledge of the molecular mechanisms underlying LC progression by exploring the role of miR-892a in the viability of TU212 and M4E cells. The results showed that miR-892a, which exhibited elevated expression in LC cells and tissue specimens of patients with LC, exerted an inhibitory effect on Dicer expression, whereas silencing of miR-892a in TU212 and M4E cells hindered cell proliferation and growth and promoted apoptosis. Furthermore, miR-892a was demonstrated to directly target Dicer 3'-UTR and inhibit its expression. These findings demonstrated that miR-892a acted as an LC oncogene via its action on Dicer, which further confirmed that miR-892a can serve as a diagnostic indicator or promising agent for LC treatment.


Assuntos
Proliferação de Células/genética , Neoplasias Laríngeas/genética , Neoplasias Laríngeas/patologia , MicroRNAs/genética , Regiões 3' não Traduzidas/genética , Apoptose/genética , Linhagem Celular , Linhagem Celular Tumoral , Progressão da Doença , Células Epiteliais/patologia , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Masculino , Pessoa de Meia-Idade , Nasofaringe/patologia
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