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1.
Nat Immunol ; 22(12): 1503-1514, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34716452

RESUMO

Prevention of viral escape and increased coverage against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern require therapeutic monoclonal antibodies (mAbs) targeting multiple sites of vulnerability on the coronavirus spike glycoprotein. Here we identify several potent neutralizing antibodies directed against either the N-terminal domain (NTD) or the receptor-binding domain (RBD) of the spike protein. Administered in combinations, these mAbs provided low-dose protection against SARS-CoV-2 infection in the K18-human angiotensin-converting enzyme 2 mouse model, using both neutralization and Fc effector antibody functions. The RBD mAb WRAIR-2125, which targets residue F486 through a unique heavy-chain and light-chain pairing, demonstrated potent neutralizing activity against all major SARS-CoV-2 variants of concern. In combination with NTD and other RBD mAbs, WRAIR-2125 also prevented viral escape. These data demonstrate that NTD/RBD mAb combinations confer potent protection, likely leveraging complementary mechanisms of viral inactivation and clearance.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , COVID-19/imunologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/metabolismo , Anticorpos Neutralizantes/química , Anticorpos Neutralizantes/metabolismo , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/metabolismo , Sítios de Ligação/genética , COVID-19/metabolismo , COVID-19/prevenção & controle , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Mapeamento de Epitopos , Epitopos/química , Epitopos/imunologia , Epitopos/metabolismo , Humanos , Camundongos Transgênicos , Testes de Neutralização , Ligação Proteica , Conformação Proteica , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Homologia de Sequência de Aminoácidos , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Análise de Sobrevida
2.
Immunity ; 55(11): 2135-2148.e6, 2022 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-36306784

RESUMO

Epstein-Barr virus (EBV) is nearly ubiquitous in adults. EBV causes infectious mononucleosis and is associated with B cell lymphomas, epithelial cell malignancies, and multiple sclerosis. The EBV gH/gL glycoprotein complex facilitates fusion of virus membrane with host cells and is a target of neutralizing antibodies. Here, we examined the sites of vulnerability for virus neutralization and fusion inhibition within EBV gH/gL. We developed a panel of human monoclonal antibodies (mAbs) that targeted five distinct antigenic sites on EBV gH/gL and prevented infection of epithelial and B cells. Structural analyses using X-ray crystallography and electron microscopy revealed multiple sites of vulnerability and defined the antigenic landscape of EBV gH/gL. One mAb provided near-complete protection against viremia and lymphoma in a humanized mouse EBV challenge model. Our findings provide structural and antigenic knowledge of the viral fusion machinery, yield a potential therapeutic antibody to prevent EBV disease, and emphasize gH/gL as a target for herpesvirus vaccines and therapeutics.


Assuntos
Infecções por Vírus Epstein-Barr , Herpesvirus Humano 4 , Cricetinae , Camundongos , Animais , Humanos , Proteínas do Envelope Viral , Cricetulus , Glicoproteínas de Membrana , Células CHO
3.
Int J Med Sci ; 21(6): 1064-1071, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38774744

RESUMO

Hyperlipidemia is notorious for causing coronary artery disease (CAD). IL-18 is a proinflammtory cytokine that contributes to the pathogenesis of CAD. Previous reports have revealed that genetic polymorphism of IL-18 is associated with its expression level as well as the susceptibility to CAD. In the present study, we aim to investigate the relationship between IL-18 single nucleotide polymorphisms (SNPs) and hyperlipidemia in the Han Chinese population in Taiwan. A total of 580 participants older than 30 were recruited from the community. We collected the demographics, self-reported disease histories, and lifestyles. We also assessed the levels of lipid profiles including total cholesterol (CHOL), triglyceride, low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol. Two SNPs, rs3882891C/A (intron 5) and rs1946518A/C (promoter -607) of IL-18 were elucidated by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) methods. Our results revealed that rs3882891 AA was associated with lower risk of hypercholesterolemia, higher CHOL and LDL-C in subjects (p=0.003, p=0.000 and p=0.005 separately), and rs1946518 CC was associated with hypercholesterolemia, higher CHOL and LDL-C as well (p=0.021, p=0.003 and p=0.001 separately) Furthermore, both SNPs were associated with IL-18 expression level, which was examined by Genotype-Tissue Expression (GTEx) Portal (p=0.042 and 0.016 separately). Finally, the haplotype of IL-18 was subsequently arranged in the order of rs3882891 and rs1946518. The result revealed that the AC haplotype of 2 IL-18 SNPs was also associated with lower risk of hypercholesterolemia, lower levels of CHOL and LDL-C (p=0.01, p=0.001 and 0.003). The current study is the first to report the association between IL-18 SNPs and hyperlipidemia in the Chinese Han population.


Assuntos
Predisposição Genética para Doença , Hiperlipidemias , Interleucina-18 , Polimorfismo de Nucleotídeo Único , Humanos , Interleucina-18/genética , Masculino , Pessoa de Meia-Idade , Feminino , Hiperlipidemias/genética , Adulto , Taiwan/epidemiologia , Povo Asiático/genética , Idoso , Haplótipos/genética , Doença da Artéria Coronariana/genética , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/epidemiologia , LDL-Colesterol/sangue , Estudos de Associação Genética
4.
Proc Natl Acad Sci U S A ; 118(38)2021 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-34470866

RESUMO

Emergence of novel variants of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) underscores the need for next-generation vaccines able to elicit broad and durable immunity. Here we report the evaluation of a ferritin nanoparticle vaccine displaying the receptor-binding domain of the SARS-CoV-2 spike protein (RFN) adjuvanted with Army Liposomal Formulation QS-21 (ALFQ). RFN vaccination of macaques using a two-dose regimen resulted in robust, predominantly Th1 CD4+ T cell responses and reciprocal peak mean serum neutralizing antibody titers of 14,000 to 21,000. Rapid control of viral replication was achieved in the upper and lower airways of animals after high-dose SARS-CoV-2 respiratory challenge, with undetectable replication within 4 d in seven of eight animals receiving 50 µg of RFN. Cross-neutralization activity against SARS-CoV-2 variant B.1.351 decreased only approximately twofold relative to WA1/2020. In addition, neutralizing, effector antibody and cellular responses targeted the heterotypic SARS-CoV-1, highlighting the broad immunogenicity of RFN-ALFQ for SARS-CoV-like Sarbecovirus vaccine development.


Assuntos
Vacinas contra COVID-19/administração & dosagem , COVID-19/virologia , Macaca mulatta/imunologia , Nanopartículas/química , Receptores Virais/metabolismo , SARS-CoV-2/imunologia , Adjuvantes Imunológicos/administração & dosagem , Animais , Anticorpos Neutralizantes/biossíntese , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/biossíntese , Anticorpos Antivirais/imunologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/imunologia , Ferritinas/química , SARS-CoV-2/metabolismo , Linfócitos T/imunologia
5.
Int J Mol Sci ; 25(4)2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38397057

RESUMO

Ischemic stroke, the most prevalent form of stroke, leads to neurological impairment due to cerebral ischemia and affects 55-90% of the population. Brain-derived neurotrophic factor (BDNF) plays a crucial role in the central nervous system and regulates cardiometabolic risk factors, including lipids. This single-center study aimed to explore the relationship between lipid profiles and BDNF levels in 90 patients who had experienced AIS for the first time. The results show that the high BDNF group (≥3.227 ng/mL) had significantly higher HbA1C and TG levels; ratios of TC/HDL-C, LDL-C/HDL-C, and TG/HDL-C; and percentage of hyperlipidemia (60%) as well as lower levels of HDL-C, with an OR of 1.903 (95% CI: 1.187-3.051) for TG/HDL-C, 1.975 (95% CI: 1.188-3.284) for TC/HDL-C, and 2.032 (95% CI: 1.113-3.711) for LDL-C/HDL-C. Plasma BDNF levels were found to be significantly positively correlated with TG and negatively with HDL-C, with OR values of 1.017 (95% CI: 1.003-1.030) and 0.926 (95% CI: 0.876-0.978), respectively. TC/HDL-C, TG/HDL-C, and LDL-C/HDL-C ratios are associated with BDNF levels in AIS patients. The results also indicate that, in AIS patients, higher BDNF levels are associated with lower HDL and higher TG concentrations.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , AVC Isquêmico , Humanos , Fator Neurotrófico Derivado do Encéfalo/metabolismo , HDL-Colesterol , LDL-Colesterol , Triglicerídeos
6.
PLoS Pathog ; 17(6): e1009624, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34086838

RESUMO

A primary goal of HIV-1 vaccine development is the consistent elicitation of protective, neutralizing antibodies. While highly similar neutralizing antibodies (nAbs) have been isolated from multiple HIV-infected individuals, it is unclear whether vaccination can consistently elicit highly similar nAbs in genetically diverse primates. Here, we show in three outbred rhesus macaques that immunization with Env elicits a genotypically and phenotypically conserved nAb response. From these vaccinated macaques, we isolated four antibody lineages that had commonalities in immunoglobulin variable, diversity, and joining gene segment usage. Atomic-level structures of the antigen binding fragments of the two most similar antibodies showed nearly identical paratopes. The Env binding modes of each of the four vaccine-induced nAbs were distinct from previously known monoclonal HIV-1 neutralizing antibodies, but were nearly identical to each other. The similarities of these antibodies show that the immune system in outbred primates can respond to HIV-1 Env vaccination with a similar structural and genotypic solution for recognizing a particular neutralizing epitope. These results support rational vaccine design for HIV-1 that aims to reproducibly elicit, in genetically diverse primates, nAbs with specific paratope structures capable of binding conserved epitopes.


Assuntos
Vacinas contra a AIDS/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Anti-HIV/imunologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia , Animais , Infecções por HIV/imunologia , HIV-1/imunologia , Humanos , Macaca mulatta
7.
Headache ; 63(6): 822-833, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37232343

RESUMO

OBJECTIVE: To explore whether patients with chronic migraine and medication overuse headache (CM + MOH) present with decision-making deficit. BACKGROUND: Factors underlying MOH in patients with CM remain unclear. Whether the process of decision-making plays a role in MOH is still controversial. Decision-making varies in the degree of uncertainty: under ambiguity where the probability of outcome is unknown, and under risk where probabilities are known. METHODS: Decisions under ambiguity and risk were assessed with the Iowa Gambling Task and the Cambridge Gambling Task, respectively, whereas executive function was assessed by the Wisconsin Card Sorting Test. RESULTS: A total of 75 participants: 25 patients with CM + MOH, 25 with CM, and 25 age- and sex-similar healthy controls (HCs), completed this cross-sectional study. There was no significant difference in headache profiles except for more frequent analgesic use (mean ± SD: 23.5 ± 7.6 vs. 6.8 ± 3.4 days; p < 0.001) and higher Severity of Dependence Scores (median [25th-75th percentile]: 8 [5-11] vs. 1 [0-4]; p < 0.001) in patients with CM + MOH compared to CM. Total net score (mean ± SD) on the Iowa Gambling Task in patients with CM + MOH, CM, and HCs were - 8.1 ± 28.7, 10.9 ± 29.6, and 14.2 ± 28.8, respectively. There was a significant difference between the three groups (F(2, 72) = 4.28, p = 0.017), with patients with CM + MOH making significantly more disadvantageous decisions than patients with CM (p = 0.024) and HCs (p = 0.008), while the CM and HC groups did not differ (p = 0.690). By contrast, there was no significant difference between the groups in the Cambridge Gambling Task and the Wisconsin Card Sorting Test. Furthermore, performance on the Iowa Gambling Task was inversely correlated with analgesic consumption (r = -0.41, p = 0.003), suggesting that decision-making under ambiguity may be related to MOH. CONCLUSIONS: Our data suggest that patients with CM + MOH had impaired decisions under ambiguous, but not risky situations. This dissociation indicates disrupted emotional feedback processing rather than executive dysfunction, which may underlie the pathogenesis of MOH.


Assuntos
Tomada de Decisões , Transtornos de Enxaqueca , Humanos , Assunção de Riscos , Estudos Transversais , Uso Excessivo de Medicamentos Prescritos , Testes Neuropsicológicos
8.
Medicina (Kaunas) ; 60(1)2023 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-38256339

RESUMO

Background and Objectives: Systemic lupus erythematosus (SLE) is a disease with multiple organ involvement, and spontaneous hemorrhage, especially perirenal hemorrhage, is rare. Case Presentation: We report the case of a 19-year-old teenager with SLE who experienced left flank pain and hypovolemic shock. Abdominal computed tomography revealed a large left retroperitoneal hematoma. Recurrent hypovolemic shock occurred despite the transcatheter arterial embolization of the left renal artery. Repetitive abdominal computed tomography results showed active hemorrhage. Result: An exploratory laparotomy was used to confirm descending colonic mesenteric artery bleeding, which was resolved. The patient needed temporary regular kidney replacement therapy for active lupus nephritis, which terminated one month after discharge. Conclusions: When patients with SLE experience acute abdominal pain, flank pain, or back pain combined with hypovolemia, there is a higher risk of bleeding due to spontaneous hemorrhage, which should be included in the differential diagnosis. Therefore, early diagnosis and adequate emergency intervention are necessary.


Assuntos
Lúpus Eritematoso Sistêmico , Nefrite Lúpica , Choque , Adolescente , Humanos , Adulto Jovem , Adulto , Lúpus Eritematoso Sistêmico/complicações , Hemorragia Gastrointestinal , Hematoma/complicações
9.
Biometals ; 29(3): 377-88, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27146331

RESUMO

Siderophores are structurally diverse, complex natural products that bind metals with extraordinary specificity and affinity. The acquisition of iron is critical for the survival and virulence of many pathogenic microbes and diverse strategies have evolved to synthesize, import and utilize iron. There has been a substantial increase of known siderophore scaffolds isolated and characterized in the past decade and the corresponding biosynthetic gene clusters have provided insight into the varied pathways involved in siderophore biosynthesis, delivery and utilization. Additionally, therapeutic applications of siderophores and related compounds are actively being developed. The study of biosynthetic pathways to natural siderophores augments the understanding of the complex mechanisms of bacterial iron acquisition, and enables a complimentary approach to address virulence through the interruption of siderophore biosynthesis or utilization by targeting the key enzymes to the siderophore pathways.


Assuntos
Bactérias/metabolismo , Ferro/metabolismo , Sideróforos/uso terapêutico , Animais , Bactérias/química , Humanos , Ferro/química , Sideróforos/biossíntese , Sideróforos/química
10.
Biochemistry ; 54(25): 3989-4000, 2015 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-26043104

RESUMO

Microbial iron acquisition is a complex process and frequently a key and necessary step for survival. Among the several paths for iron assimilation, small molecule siderophore-mediated transport is a commonly employed strategy of many microorganisms. The chemistry and biology of the extraordinary tight and specific binding of siderophores to metal is also exploited in therapeutic treatments for microbial virulence and metal toxicity. The intracellular fate of iron acquired via the siderophore pathway is one of the least understood steps in the complex process at the molecular level. A common route to cellular incorporation is the single-electron reduction of ferric to ferrous iron catalyzed by specific and/or nonspecific reducing agents. The biosynthetic gene clusters for siderophores often contain representatives of one or two families of redox-active enzymes: the flavin-containing "siderophore-interacting protein" and iron-sulfur ferric siderophore reductases. Here we present the structure and characterization of the siderophore-interacting protein, FscN, from the fuscachelin siderophore gene cluster of Thermobifida fusca. The structure shows a flavoreductase fold with a noncovalently bound FAD cofactor along with an unexpected metal bound adjacent to the flavin site. We demonstrated that FscN is redox-active and measured the binding and reduction of ferric fuscachelin. This work provides a structural basis for the activity of a siderophore-interacting protein and further insight into the complex and important process of iron acquisition and utilization.


Assuntos
Actinobacteria/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Família Multigênica , Sideróforos/metabolismo , Actinobacteria/química , Actinobacteria/genética , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Modelos Moleculares , Dados de Sequência Molecular , Ligação Proteica , Alinhamento de Sequência , Sideróforos/química
11.
Opt Express ; 23(2): 982-90, 2015 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-25835857

RESUMO

This paper presents a novel optical single-sideband (SSB) OFDM modulation scheme using a two-segment electro-absorption modulator (EAM). Differences in the chirp characteristics of two segments of the EAM make it possible to design driving signals capable of suppressing one of the optical sidebands, such that the optical OFDM signal does not suffer from frequency-selective power fading following dispersive fiber transmission. Our experiment results demonstrate optical OFDM transmissions at 13.5-Gbps over a 0 ∼ 200-km IM/DD system without the need for dispersion compensation and distance-dependent bit- and power-loading.

12.
Can J Anaesth ; 62(4): 369-76, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25608641

RESUMO

INTRODUCTION: This study explored the effects of general (GA) and neuraxial (NA) anesthesia on the outcomes of primary total joint replacement (TJR) in terms of postoperative mortality, length of stay (LOS), and hospital treatment costs. METHODS: From 1997 to 2010, this nationwide population-based study retrospectively evaluated 7,977 patients in Taiwan who underwent primary total hip or knee replacement. We generated two propensity-score-matched subgroups, each containing an equal number of patients who underwent TJR with either GA or NA. RESULTS: Of the 7,977 patients, 2,990 (37.5%) underwent GA and 4,987 (62.5%) underwent NA. Propensity-score matching was used to create comparable GA and NA groups adjusted for age, sex, comorbidities, surgery type, hospital volume, and surgeon volume. Survival over the first three years following surgery was similar. The proportion of patients alive up to 14 years postoperatively for those undergoing NA was 58.2% (95% confidence interval [CI] 50.4 to 66.0), and for those undergoing GA it was 57.3% (95% CI 51.4 to 63.2). Neuraxial anesthesia was associated with lower median [interquartile range; IQR] hospital treatment cost ($4,079 [3,805-4,444] vs $4,113 [3,812-4,568]; P < 0.001) and shorter median [IQR] LOS (8 [7-10] days vs 8 [6-10] days, respectively; P = 0.024). CONCLUSIONS: Our results support the use of NA for primary TJR. The improvements in hospital costs persist even when anesthesia costs are removed. The mechanism underlying the association between NA and long-term survival is unknown.


Assuntos
Anestesia por Condução/métodos , Anestesia Geral/métodos , Artroplastia de Quadril/métodos , Artroplastia do Joelho/métodos , Idoso , Anestesia por Condução/economia , Anestesia Geral/economia , Artroplastia de Quadril/economia , Artroplastia do Joelho/economia , Feminino , Seguimentos , Custos Hospitalares , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/mortalidade , Pontuação de Propensão , Estudos Retrospectivos , Taxa de Sobrevida , Taiwan
13.
Lancet Microbe ; 5(6): e581-e593, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38761816

RESUMO

BACKGROUND: A self-assembling SARS-CoV-2 WA-1 recombinant spike ferritin nanoparticle (SpFN) vaccine co-formulated with Army Liposomal Formulation (ALFQ) adjuvant containing monophosphoryl lipid A and QS-21 (SpFN/ALFQ) has shown protective efficacy in animal challenge models. This trial aims to assess the safety and immunogenicity of SpFN/ALFQ in a first-in-human clinical trial. METHODS: In this phase 1, randomised, double-blind, placebo-controlled, first-in-human clinical trial, adults were randomly assigned (5:5:2) to receive 25 µg or 50 µg of SpFN/ALFQ or saline placebo intramuscularly at day 1 and day 29, with an optional open-label third vaccination at day 181. Enrolment and randomisation occurred sequentially by group; randomisation was done by an interactive web-based randomisation system and only designated unmasked study personnel had access to the randomisation code. Adults were required to be seronegative and unvaccinated for inclusion. Local and systemic reactogenicity, adverse events, binding and neutralising antibodies, and antigen-specific T-cell responses were quantified. For safety analyses, exact 95% Clopper-Pearson CIs for the probability of any incidence of an unsolicited adverse event was computed for each group. For immunogenicity results, CIs for binary variables were computed using the exact Clopper-Pearson methodology, while CIs for geometric mean titres were based on 10 000 empirical bootstrap samples. Post-hoc, paired one-sample t tests were used to assess the increase in mean log-10 neutralising antibody titres between day 29 and day 43 (after the second vaccination) for the primary SARS-CoV-2 targets of interest. This trial is registered at ClinicalTrials.gov, NCT04784767, and is closed to new participants. FINDINGS: Between April 7, and June 29, 2021, 29 participants were enrolled in the study. 20 individuals were assigned to receive 25 µg SpFN/ALFQ, four to 50 µg SpFN/ALFQ, and five to placebo. Neutralising antibody responses peaked at day 43, 2 weeks after the second dose. Neutralisation activity against multiple omicron subvariants decayed more slowly than against the D614G or beta variants until 5 months after second vaccination for both dose groups. CD4+ T-cell responses were elicited 4 weeks after the first dose and were boosted after a second dose of SpFN/ALFQ for both dose groups. Neutralising antibody titres against early omicron subvariants and clade 1 sarbecoviruses were detectable after two immunisations and peaked after the third immunisation for both dose groups. Neutralising antibody titres against XBB.1.5 were detected after three vaccinations. Passive IgG transfer from vaccinated volunteers into Syrian golden hamsters controlled replication of SARS-CoV-1 after challenge. INTERPRETATION: SpFN/ALFQ was well tolerated and elicited robust and durable binding antibody and neutralising antibody titres against a broad panel of SARS-CoV-2 variants and other sarbecoviruses. FUNDING: US Department of Defense, Defense Health Agency.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Ferritinas , Lipídeo A , Lipossomos , Nanopartículas , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Humanos , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/administração & dosagem , Vacinas contra COVID-19/efeitos adversos , Método Duplo-Cego , Adulto , Masculino , Feminino , COVID-19/prevenção & controle , COVID-19/imunologia , SARS-CoV-2/imunologia , Nanopartículas/administração & dosagem , Lipídeo A/análogos & derivados , Lipídeo A/administração & dosagem , Lipídeo A/farmacologia , Lipídeo A/imunologia , Lipossomos/administração & dosagem , Glicoproteína da Espícula de Coronavírus/imunologia , Saponinas/administração & dosagem , Saponinas/imunologia , Saponinas/farmacologia , Saponinas/efeitos adversos , Anticorpos Antivirais/sangue , Pessoa de Meia-Idade , Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/farmacologia , Adjuvantes de Vacinas/administração & dosagem , Anticorpos Neutralizantes/sangue , Adulto Jovem , Nanovacinas
14.
Nat Commun ; 15(1): 200, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172512

RESUMO

The repeat emergence of SARS-CoV-2 variants of concern (VoC) with decreased susceptibility to vaccine-elicited antibodies highlights the need to develop next-generation vaccine candidates that confer broad protection. Here we describe the antibody response induced by the SARS-CoV-2 Spike Ferritin Nanoparticle (SpFN) vaccine candidate adjuvanted with the Army Liposomal Formulation including QS21 (ALFQ) in non-human primates. By isolating and characterizing several monoclonal antibodies directed against the Spike Receptor Binding Domain (RBD), N-Terminal Domain (NTD), or the S2 Domain, we define the molecular recognition of vaccine-elicited cross-reactive monoclonal antibodies (mAbs) elicited by SpFN. We identify six neutralizing antibodies with broad sarbecovirus cross-reactivity that recapitulate serum polyclonal antibody responses. In particular, RBD mAb WRAIR-5001 binds to the conserved cryptic region with high affinity to sarbecovirus clades 1 and 2, including Omicron variants, while mAb WRAIR-5021 offers complete protection from B.1.617.2 (Delta) in a murine challenge study. Our data further highlight the ability of SpFN vaccination to stimulate cross-reactive B cells targeting conserved regions of the Spike with activity against SARS CoV-1 and SARS-CoV-2 variants.


Assuntos
Nanopartículas , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave , Animais , Camundongos , Anticorpos Neutralizantes , Macaca mulatta , Vacinação , Anticorpos Antivirais , Anticorpos Monoclonais , Vacinas contra COVID-19 , Ferritinas , Glicoproteína da Espícula de Coronavírus/genética
15.
Structure ; 32(2): 131-147.e7, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38157856

RESUMO

Given the continuous emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern (VoCs), immunotherapeutics that target conserved epitopes on the spike (S) glycoprotein have therapeutic advantages. Here, we report the crystal structure of the SARS-CoV-2 S receptor-binding domain (RBD) at 1.95 Å and describe flexibility and distinct conformations of the angiotensin-converting enzyme 2 (ACE2)-binding site. We identify a set of SARS-CoV-2-reactive monoclonal antibodies (mAbs) with broad RBD cross-reactivity including SARS-CoV-2 Omicron subvariants, SARS-CoV-1, and other sarbecoviruses and determine the crystal structures of mAb-RBD complexes with Ab246 and CR3022 mAbs targeting the class IV site, WRAIR-2134, which binds the recently designated class V epitope, and WRAIR-2123, the class I ACE2-binding site. The broad reactivity of class IV and V mAbs to conserved regions of SARS-CoV-2 VoCs and other sarbecovirus provides a framework for long-term immunotherapeutic development strategies.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/metabolismo , Enzima de Conversão de Angiotensina 2/metabolismo , Anticorpos Neutralizantes/química , Anticorpos Antivirais/química , Sítios de Ligação , Epitopos
16.
Artif Organs ; 37(12): 1076-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23865547

RESUMO

Assessment of respiratory function using combined oximetry-cutaneous capnography has never been evaluated in patients with myasthenia gravis (MG). We investigated the effects of double filtration plasmapheresis (DFPP) on respiratory status in 18 MG patients. Results of combined oximetry and transcutaneous capnography, MG scores, and acetylcholine receptor antibody titers before and after DFPP treatment were compared. The respiratory monitoring was performed at three time periods (morning, afternoon, and sleep). Mean MG score was markedly lower after DFPP treatment (5.7) than before treatment (7.9). Before DFPP, the minimum pulse oximetric saturation (SpO2 ) level obtained during the night session was significantly lower (P = 0.0513 and P = 0.0199) than the levels obtained during the two daytime sessions. A similar phenomenon was noted for maximum transcutaneous carbon dioxide tension (PtcCO2 ). After DFPP treatment, the maximum and mean PtcCO2 levels were significantly higher (P = 0.0056) in the morning than in the afternoon. Of all the respiratory function parameters measured, only minimum SpO2 levels obtained during morning sessions before DFP treatment differed significantly from those obtained after DFPP treatment (P = 0.0322). Overall, however, minimum SpO2 levels as well as mean and maximum PtcCO2 levels improved significantly during sleep after DFPP. In conclusion, we found that respiratory function abnormalities were common in myasthenic patients without clinical respiratory symptoms. DFPP treatment resulted in minimal improvement of respiratory parameters.


Assuntos
Autoanticorpos/sangue , Ritmo Circadiano , Pulmão/fisiopatologia , Miastenia Gravis/terapia , Plasmaferese/métodos , Receptores Colinérgicos/imunologia , Respiração , Adolescente , Adulto , Idoso , Capnografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Miastenia Gravis/sangue , Miastenia Gravis/diagnóstico , Miastenia Gravis/imunologia , Miastenia Gravis/fisiopatologia , Oximetria , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
17.
Diagnostics (Basel) ; 13(13)2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37443691

RESUMO

Brain-derived neurotrophic factor (BDNF) interacts with tropomyosin-related kinase B (TrkB) to promote neuronal growth, survival, differentiation, neurotransmitter release, and synaptic plasticity. The translocator protein (TSPO) is known to be found in arterial plaques, which are a symptom of atherosclerosis and a contributory cause of ischemic stroke. This study aims to determine the diagnostic accuracy of plasma BDNF and TSPO levels in discriminating new-onset acute ischemic stroke (AIS) patients from individuals without acute ischemic stroke. A total of 90 AIS patients (61% male, with a mean age of 67.7 ± 12.88) were recruited consecutively in a stroke unit, and each patient was paired with two age- and gender-matched controls. The sensitivity, specificity, and area of the curve between high plasma BDNF and TSPO and having AIS was determined using receiver operating characteristic curves. Furthermore, compared to the controls, AIS patients exhibited significantly higher levels of BDNF and TSPO, blood pressure, HbA1c, and white blood cells, as well as higher creatinine levels. The plasma levels of BDNF and TSPO can significantly discriminate AIS patients from healthy individuals (AUC 0.76 and 0.89, respectively). However, combining the two biomarkers provided little improvement in AUC (0.90). It may be possible to use elevated levels of TSPO as a diagnostic biomarker in patients with acute ischemic stroke upon admission.

18.
Bioengineering (Basel) ; 10(10)2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37892920

RESUMO

Recently, studies have revealed that human herpesvirus 4 (HHV-4), also known as the Epstein-Barr virus, might be associated with the severity of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Compared to SARS-CoV-2 infection alone, patients coinfected with SARS-CoV-2 and HHV-4 had higher risks of fever, inflammation, and even death, thus, confirming that HHV-4/SARS-CoV-2 coinfection in patients could benefit from clinical investigation. Although several intelligent devices can simultaneously discern multiple genes related to SARS-CoV-2, most operate via label-based detection, which restricts them from directly measuring the product. In this study, we developed a device that can replicate and detect SARS-CoV-2 and HHV-4 DNA. This device can conduct a duplex polymerase chain reaction (PCR) in a microfluidic channel and detect replicates in a non-labeled manner through a plasmonic-based sensor. Compared to traditional instruments, this device can reduce the required PCR time by 55% while yielding a similar amount of amplicon. Moreover, our device's limit of detection (LOD) reached 100 fg/mL, while prior non-labeled sensors for SARS-CoV-2 detection were in the range of ng/mL to pg/mL. Furthermore, the device can detect desired genes by extracting cells artificially infected with HHV-4/SARS-CoV-2. We expect that this device will be able to help verify HHV-4/SARS-CoV-2 coinfected patients and assist in the evaluation of practical treatment approaches.

19.
NPJ Vaccines ; 8(1): 43, 2023 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-36934088

RESUMO

This study demonstrates the impact of adjuvant on the development of T follicular helper (Tfh) and B cells, and their influence on antibody responses in mice vaccinated with SARS-CoV-2-spike-ferritin-nanoparticle (SpFN) adjuvanted with either Army Liposome Formulation containing QS-21 (SpFN + ALFQ) or Alhydrogel® (SpFN + AH). SpFN + ALFQ increased the size and frequency of germinal center (GC) B cells in the vaccine-draining lymph nodes and increased the frequency of antigen-specific naive B cells. A single vaccination with SpFN + ALFQ resulted in a higher frequency of IL-21-producing-spike-specific Tfh and GC B cells in the draining lymph nodes and spleen, S-2P protein-specific IgM and IgG antibodies, and elicitation of robust cross-neutralizing antibodies against SARS-CoV-2 variants as early as day 7, which was enhanced by a second vaccination. This was associated with the generation of high titer, high avidity binding antibodies. The third vaccination with SpFN + ALFQ elicited high levels of neutralizing antibodies against the Omicron variant. No cross-neutralizing antibodies against Omicron were induced with SpFN + AH. These findings highlight the importance of ALFQ in orchestrating early induction of antigen-specific Tfh and GC B cell responses and long-lived plasma cells in the bone marrow. The early engagement of S-2P specific naive B cells and high titer IgM antibodies shape the development of long-term neutralization breadth.

20.
Cell Rep Med ; 4(4): 101018, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-37023746

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines demonstrate reduced protection against acquisition of BA.5 subvariant but are still effective against severe disease. However, immune correlates of protection against BA.5 remain unknown. We report the immunogenicity and protective efficacy of vaccine regimens consisting of the vector-based Ad26.COV2.S vaccine and the adjuvanted spike ferritin nanoparticle (SpFN) vaccine against a high-dose, mismatched Omicron BA.5 challenge in macaques. The SpFNx3 and Ad26 + SpFNx2 regimens elicit higher antibody responses than Ad26x3, whereas the Ad26 + SpFNx2 and Ad26x3 regimens induce higher CD8 T cell responses than SpFNx3. The Ad26 + SpFNx2 regimen elicits the highest CD4 T cell responses. All three regimens suppress peak and day 4 viral loads in the respiratory tract, which correlate with both humoral and cellular immune responses. This study demonstrates that both homologous and heterologous regimens involving Ad26.COV2.S and SpFN vaccines provide robust protection against a mismatched BA.5 challenge in macaques.


Assuntos
COVID-19 , Nanopartículas , Vacinas , Humanos , Animais , Macaca , Ad26COVS1 , COVID-19/prevenção & controle , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Ferritinas
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