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1.
Nat Immunol ; 24(10): 1711-1724, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37735592

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection of vaccinated individuals is increasingly common but rarely results in severe disease, likely due to the enhanced potency and accelerated kinetics of memory immune responses. However, there have been few opportunities to rigorously study early recall responses during human viral infection. To better understand human immune memory and identify potential mediators of lasting vaccine efficacy, we used high-dimensional flow cytometry and SARS-CoV-2 antigen probes to examine immune responses in longitudinal samples from vaccinated individuals infected during the Omicron wave. These studies revealed heightened spike-specific responses during infection of vaccinated compared to unvaccinated individuals. Spike-specific cluster of differentiation (CD)4 T cells and plasmablasts expanded and CD8 T cells were robustly activated during the first week. In contrast, memory B cell activation, neutralizing antibody production and primary responses to nonspike antigens occurred during the second week. Collectively, these data demonstrate the functionality of vaccine-primed immune memory and highlight memory T cells as rapid responders during SARS-CoV-2 infection.

2.
Proc Natl Acad Sci U S A ; 121(29): e2310421121, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38976733

RESUMO

We generated a replication-competent OC43 human seasonal coronavirus (CoV) expressing the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike in place of the native spike (rOC43-CoV2 S). This virus is highly attenuated relative to OC43 and SARS-CoV-2 in cultured cells and animals and is classified as a biosafety level 2 (BSL-2) agent by the NIH biosafety committee. Neutralization of rOC43-CoV2 S and SARS-CoV-2 by S-specific monoclonal antibodies and human sera is highly correlated, unlike recombinant vesicular stomatitis virus-CoV2 S. Single-dose immunization with rOC43-CoV2 S generates high levels of neutralizing antibodies against SARS-CoV-2 and fully protects human ACE2 transgenic mice from SARS-CoV-2 lethal challenge, despite nondetectable replication in respiratory and nonrespiratory organs. rOC43-CoV2 S induces S-specific serum and airway mucosal immunoglobulin A and IgG responses in rhesus macaques. rOC43-CoV2 S has enormous value as a BSL-2 agent to measure S-specific antibodies in the context of a bona fide CoV and is a candidate live attenuated SARS-CoV-2 mucosal vaccine that preferentially replicates in the upper airway.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19 , Testes de Neutralização , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Animais , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/genética , SARS-CoV-2/imunologia , SARS-CoV-2/genética , Humanos , Anticorpos Neutralizantes/imunologia , Camundongos , COVID-19/imunologia , COVID-19/virologia , COVID-19/prevenção & controle , Anticorpos Antivirais/imunologia , Testes de Neutralização/métodos , Camundongos Transgênicos , Coronavirus Humano OC43/imunologia , Coronavirus Humano OC43/genética , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/administração & dosagem , Enzima de Conversão de Angiotensina 2/metabolismo , Enzima de Conversão de Angiotensina 2/imunologia , Chlorocebus aethiops , Células Vero , Macaca mulatta
3.
Proc Natl Acad Sci U S A ; 120(28): e2304087120, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37399385

RESUMO

We recently reported that SARS-CoV-2 nucleocapsid (N) protein is abundantly expressed on the surface of both infected and neighboring uninfected cells, where it enables activation of Fc receptor-bearing immune cells with anti-N antibodies (Abs) and inhibits leukocyte chemotaxis by binding chemokines (CHKs). Here, we extend these findings to N from the common cold human coronavirus (HCoV)-OC43, which is also robustly expressed on the surface of infected and noninfected cells by binding heparan sulfate/heparin (HS/H). HCoV-OC43 N binds with high affinity to the same set of 11 human CHKs as SARS-CoV-2 N, but also to a nonoverlapping set of six cytokines. As with SARS-CoV-2 N, HCoV-OC43 N inhibits CXCL12ß-mediated leukocyte migration in chemotaxis assays, as do all highly pathogenic and common cold HCoV N proteins. Together, our findings indicate that cell surface HCoV N plays important evolutionarily conserved roles in manipulating host innate immunity and as a target for adaptive immunity.


Assuntos
Coronavirus Humano OC43 , Imunidade Inata , Nucleocapsídeo , SARS-CoV-2 , Humanos , Coronavirus Humano OC43/genética , Proteínas de Membrana , SARS-CoV-2/genética
4.
Proc Natl Acad Sci U S A ; 120(35): e2216521120, 2023 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-37603748

RESUMO

The constant domains of antibodies are important for effector functions, but less is known about how they can affect binding and neutralization of viruses. Here, we evaluated a panel of human influenza virus monoclonal antibodies (mAbs) expressed as IgG1, IgG2, or IgG3. We found that many influenza virus-specific mAbs have altered binding and neutralization capacity depending on the IgG subclass encoded and that these differences result from unique bivalency capacities of the subclasses. Importantly, subclass differences in antibody binding and neutralization were greatest when the affinity for the target antigen was reduced through antigenic mismatch. We found that antibodies expressed as IgG3 bound and neutralized antigenically drifted influenza viruses more effectively. We obtained similar results using a panel of SARS-CoV-2-specific mAbs and the antigenically advanced B.1.351 and BA.1 strains of SARS-CoV-2. We found that a licensed therapeutic mAb retained neutralization breadth against SARS-CoV-2 variants when expressed as IgG3, but not IgG1. These data highlight that IgG subclasses are not only important for fine-tuning effector functionality but also for binding and neutralization of antigenically drifted viruses.


Assuntos
Anticorpos Antivirais , COVID-19 , Imunoglobulina G , Influenza Humana , Imunoglobulina G/imunologia , Anticorpos Antivirais/imunologia , Fragmentos Fab das Imunoglobulinas/imunologia , Formação de Anticorpos , Influenza Humana/imunologia , Influenza Humana/virologia , COVID-19/imunologia , COVID-19/virologia , Switching de Imunoglobulina , SARS-CoV-2/fisiologia , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Humanos , Glicoproteínas de Hemaglutininação de Vírus da Influenza/metabolismo , Vírus da Influenza A/fisiologia
5.
Clin Infect Dis ; 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39041887

RESUMO

BACKGROUND: Studies have reported that repeated annual vaccination may influence influenza vaccination effectiveness in the current season. METHODS: We established a 5-year randomized placebo-controlled trial of repeated influenza vaccination (Flublok, Sanofi Pasteur) in adults 18-45 years of age. In the first two years, participants received vaccination (V) or saline placebo (P) as follows: P-P, P-V, or V-V. Serum samples were collected each year just before vaccination and after 30 and 182 days. A subset of sera collected at 5 timepoints from 95 participants were tested for antibodies against vaccine strains. RESULTS: From 23 October 2020 through 11 March 2021 we enrolled and randomized 447 adults. Among vaccinated individuals, antibody titers increased between days 0 and 30 against each of the vaccine strains, with smaller increases for repeat vaccinees who on average had higher pre-vaccination titers in year 2. There were statistically significant differences in the proportion of participants achieving >=four-fold rises in antibody titer for the repeat vaccinees for influenza A(H1N1), B/Victoria and B/Yamagata, but not for A(H3N2). Among participants who received vaccination in year 2, there were no statistically significant differences between the P-V and V-V groups in geometric mean titers at day 30 or the proportions of participants with antibody titers ≥40 at day 30 for any of the vaccine strains. CONCLUSIONS: In the first two years, during which influenza did not circulate, repeat vaccinees and first-time vaccinees had similar post-vaccination geometric mean titers to all four vaccine strains, indicative of similar levels of clinical protection.

6.
J Virol ; 97(1): e0172322, 2023 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-36533954

RESUMO

Most human influenza vaccine antigens are produced in fertilized chicken eggs. Recent H3N2 egg-based vaccine antigens have limited effectiveness, partially due to egg-adaptive substitutions that alter the antigenicity of the hemagglutinin (HA) protein. The nucleoside-modified mRNA encapsulated in lipid nanoparticles (mRNA-LNP) vaccine platform is a promising alternative for egg-based influenza vaccines because mRNA-LNP-derived antigens are not subject to adaptive pressures that arise during the production of antigens in chicken eggs. Here, we compared H3N2-specific antibody responses in mice vaccinated with either 3c.2A H3-encoding mRNA-LNP or a conventional egg-based Fluzone vaccine (which included an egg-adapted 3c.2A antigen) supplemented with an MF59-like adjuvant. We tested mRNA-LNP encoding wild-type and egg-adapted H3 antigens. We found that mRNA-LNP encoding wild-type H3 elicited antibodies that neutralized the wild-type 3c.2A H3N2 virus more effectively than antibodies elicited by mRNA-LNP encoding egg-adapted H3 or the egg-based Fluzone vaccine. mRNA-LNP expressing either wild-type or egg-adapted H3 protected mice against infection with the wild-type 3c2.A H3N2, whereas the egg-based Fluzone vaccine did not. We found that both mRNA-LNP vaccines elicited high levels of group 2 HA stalk-reactive antibodies, which likely contributed to protection in vivo. Our studies indicate that nucleoside-modified mRNA-LNP-based vaccines can circumvent problems associated with egg adaptations with recent 3c2.A H3N2 viruses. IMPORTANCE This study shows that the nucleoside-modified mRNA-LNP vaccine platform is a promising alternative for egg-based influenza vaccines. We show that mRNA-LNP vaccines expressing H3 antigens elicit high levels of antibodies in mice and protect against H3N2 influenza virus infection.


Assuntos
Vírus da Influenza A Subtipo H3N2 , Vacinas contra Influenza , Nucleosídeos , Vacinas de mRNA , Animais , Humanos , Camundongos , Anticorpos Antivirais , Galinhas , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Vírus da Influenza A Subtipo H3N2/genética , Vacinas contra Influenza/genética , Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , RNA Mensageiro/genética , Vacinas de mRNA/genética , Vacinas de mRNA/imunologia
7.
Kidney Int ; 104(3): 455-462, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37290603

RESUMO

The majority of podocyte disorders are progressive in nature leading to chronic kidney disease and often kidney failure. The scope of current therapies is typically nonspecific immunosuppressant medications, which are accompanied by unwanted and serious side effects. However, many exciting clinical trials are underway to reduce the burden of podocyte diseases in our patients. Major advances and discoveries have recently been made experimentally in our understanding of the molecular and cellular mechanisms underlying podocyte injury in disease. This begs the question of how best to take advantage of these impressive strides. One approach to consider is the repurposing of therapeutics that have already been approved by the Food and Drug Administration, European Medicines Agency, and other regulatory agencies for indications beyond the kidney. The advantages of therapy repurposing include known safety profiles, drug development that has already been completed, and overall reduced costs for studying alternative indications for selected therapies. The purpose of this mini review is to examine the experimental literature of podocyte damage and determine if there are mechanistic targets in which prior approved therapies can be considered for repurposing to podocyte disorders.


Assuntos
Podócitos , Insuficiência Renal Crônica , Humanos , Preparações Farmacêuticas , Reposicionamento de Medicamentos , Rim , Insuficiência Renal Crônica/tratamento farmacológico
8.
Kidney Int ; 103(3): 565-579, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36442540

RESUMO

The diagnosis of nephrotic syndrome relies on clinical presentation and descriptive patterns of injury on kidney biopsies, but not specific to underlying pathobiology. Consequently, there are variable rates of progression and response to therapy within diagnoses. Here, an unbiased transcriptomic-driven approach was used to identify molecular pathways which are shared by subgroups of patients with either minimal change disease (MCD) or focal segmental glomerulosclerosis (FSGS). Kidney tissue transcriptomic profile-based clustering identified three patient subgroups with shared molecular signatures across independent, North American, European, and African cohorts. One subgroup had significantly greater disease progression (Hazard Ratio 5.2) which persisted after adjusting for diagnosis and clinical measures (Hazard Ratio 3.8). Inclusion in this subgroup was retained even when clustering was limited to those with less than 25% interstitial fibrosis. The molecular profile of this subgroup was largely consistent with tumor necrosis factor (TNF) pathway activation. Two TNF pathway urine markers were identified, tissue inhibitor of metalloproteinases-1 (TIMP-1) and monocyte chemoattractant protein-1 (MCP-1), that could be used to predict an individual's TNF pathway activation score. Kidney organoids and single-nucleus RNA-sequencing of participant kidney biopsies, validated TNF-dependent increases in pathway activation score, transcript and protein levels of TIMP-1 and MCP-1, in resident kidney cells. Thus, molecular profiling identified a subgroup of patients with either MCD or FSGS who shared kidney TNF pathway activation and poor outcomes. A clinical trial testing targeted therapies in patients selected using urinary markers of TNF pathway activation is ongoing.


Assuntos
Glomerulosclerose Segmentar e Focal , Nefrologia , Nefrose Lipoide , Síndrome Nefrótica , Humanos , Glomerulosclerose Segmentar e Focal/patologia , Nefrose Lipoide/diagnóstico , Inibidor Tecidual de Metaloproteinase-1 , Síndrome Nefrótica/diagnóstico , Fatores de Necrose Tumoral/uso terapêutico
9.
Am J Transplant ; 22(2): 474-488, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34559944

RESUMO

Hispanic patients receive disproportionately fewer living donor kidney transplants (LDKTs) than non-Hispanic Whites (NHWs). The Northwestern Medicine Hispanic Kidney Transplant Program (HKTP), designed to increase Hispanic LDKTs, was evaluated as a nonrandomized, implementation-effectiveness hybrid trial of patients initiating transplant evaluation at two intervention and two similar control sites. Using a mixed method, observational design, we evaluated the fidelity of the HKTP implementation at the two intervention sites. We tested the impact of the HKTP intervention by evaluating the likelihood of receiving LDKT comparing pre-intervention (January 2011-December 2016) and postintervention (January 2017-March 2020), across ethnicity and centers. The HKTP study included 2063 recipients. Intervention Site A exhibited greater implementation fidelity than intervention Site B. For Hispanic recipients at Site A, the likelihood of receiving LDKTs was significantly higher at postintervention compared with pre-intervention (odds ratio [OR] = 3.17 95% confidence interval [1.04, 9.63]), but not at the paired control Site C (OR = 1.02 [0.61, 1.71]). For Hispanic recipients at Site B, the likelihood of receiving an LDKT did not differ between pre- and postintervention (OR = 0.88 [0.40, 1.94]). The LDKT rate was significantly lower for Hispanics at paired control Site D (OR = 0.45 [0.28, 0.90]). The intervention significantly improved LDKT rates for Hispanic patients at the intervention site that implemented the intervention with greater fidelity. Registration: ClinicalTrials.gov registered (retrospectively) on September 7, 2017 (NCT03276390).


Assuntos
Transplante de Rim , Doadores Vivos , Assistência à Saúde Culturalmente Competente , Humanos , Rim , Estudos Retrospectivos
10.
Proc Natl Acad Sci U S A ; 116(27): 13474-13479, 2019 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-31213541

RESUMO

A major obstacle to vaccination against antigenically variable viruses is skewing of antibody responses to variable immunodominant epitopes. For influenza virus hemagglutinin (HA), the immunodominance of the variable head impairs responses to the highly conserved stem. Here, we show that head immunodominance depends on the physical attachment of head to stem. Stem immunogenicity is enhanced by immunizing with stem-only constructs or by increasing local HA concentration in the draining lymph node. Surprisingly, coimmunization of full-length HA and stem alters stem-antibody class switching. Our findings delineate strategies for overcoming immunodominance, with important implications for human vaccination.


Assuntos
Anticorpos Neutralizantes/imunologia , Epitopos/imunologia , Hemaglutininas/imunologia , Epitopos Imunodominantes/imunologia , Vírus da Influenza A/imunologia , Vacinas contra Influenza/imunologia , Animais , Anticorpos Antivirais/imunologia , Linfócitos B/imunologia , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Células-Tronco/imunologia
11.
J Sport Rehabil ; 31(3): 380-384, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34689122

RESUMO

This study aimed to compare electromyographic response of the lower trapezius muscle during maximal voluntary isometric contractions under two conditions: overhead shoulder position versus scapular position, rating the pain after each condition. Twenty-six participants with shoulder pain (SP; n = 15; Shoulder Pain and Disability Index-Pain = 34 [range 6-66]) and without shoulder pain (nSP; n = 11; Shoulder Pain and Disability Index-Pain = 0 [range 0-14]) performed maximal voluntary isometric contractions in those 2 conditions while the lower trapezius was monitored using surface electromyography. Pain was rated using the visual analog scale. The nSP group experienced no pain, whereas the SP group reported pain in both conditions with higher pain during the overhead movement. No differences were observed for muscle excitation between conditions, but higher levels were observed for the nSP group compared with the SP group. The overhead condition was more painful for the SP group (visual analog scale: SP = 4 vs nSP = 1.09, P = .036). Scapular position showed the same levels of LT excitation than overhead position. The scapular position is preferable, compared with overhead positioning, to normalize the lower trapezius instead of overhead positioning.


Assuntos
Músculos Superficiais do Dorso , Eletromiografia , Humanos , Músculo Esquelético/fisiologia , Escápula/fisiologia , Ombro/fisiologia , Dor de Ombro , Músculos Superficiais do Dorso/fisiologia
12.
Am J Hum Genet ; 103(1): 131-137, 2018 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-29909964

RESUMO

Homozygous nonsense mutations in WNT2B were identified in three individuals from two unrelated families with severe, neonatal-onset osmotic diarrhea after whole-exome sequencing was performed on trios from the two families. Intestinal biopsy samples from affected individuals were used for histology and immunofluorescence and to generate enteroids ex vivo. Histopathologic evaluation demonstrated chronic inflammatory changes in the stomach, duodenum, and colon. Immunofluorescence demonstrated diminished staining for OLFM4, a marker for intestinal stem cells (ISCs). The enteroids generated from WNT2B-deficient intestinal epithelium could not be expanded and did not survive passage. Addition of CHIR-99021 (a GSK3A and GSK3B inhibitor and activator of canonical WNT/ß-CATENIN signaling) could not rescue WNT2B-deficient enteroids. Addition of supplemental recombinant murine WNT2B was able to perpetuate small enteroids for multiple passages but failed to expand their number. Enteroids showed a 10-fold increase in the expression of LEF1 mRNA and a 100-fold reduction in TLR4 expression, compared with controls by quantitative RT-PCR, indicating alterations in canonical WNT and microbial pattern-recognition signaling. In summary, individuals with homozygous nonsense mutations in WNT2B demonstrate severe intestinal dysregulation associated with decreased ISC number and function, likely explaining their diarrheal phenotype. WNT2B deficiency should be considered for individuals with neonatal-onset diarrhea.


Assuntos
Códon sem Sentido/genética , Diarreia/genética , Glicoproteínas/genética , Proteínas Wnt/genética , Criança , Pré-Escolar , Feminino , Homozigoto , Humanos , Lactente , Intestinos/patologia , Masculino , RNA Mensageiro/genética , Transdução de Sinais/genética , Células-Tronco/patologia
13.
Nature ; 523(7562): 607-11, 2015 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-26200341

RESUMO

The human lens is comprised largely of crystallin proteins assembled into a highly ordered, interactive macro-structure essential for lens transparency and refractive index. Any disruption of intra- or inter-protein interactions will alter this delicate structure, exposing hydrophobic surfaces, with consequent protein aggregation and cataract formation. Cataracts are the most common cause of blindness worldwide, affecting tens of millions of people, and currently the only treatment is surgical removal of cataractous lenses. The precise mechanisms by which lens proteins both prevent aggregation and maintain lens transparency are largely unknown. Lanosterol is an amphipathic molecule enriched in the lens. It is synthesized by lanosterol synthase (LSS) in a key cyclization reaction of a cholesterol synthesis pathway. Here we identify two distinct homozygous LSS missense mutations (W581R and G588S) in two families with extensive congenital cataracts. Both of these mutations affect highly conserved amino acid residues and impair key catalytic functions of LSS. Engineered expression of wild-type, but not mutant, LSS prevents intracellular protein aggregation of various cataract-causing mutant crystallins. Treatment by lanosterol, but not cholesterol, significantly decreased preformed protein aggregates both in vitro and in cell-transfection experiments. We further show that lanosterol treatment could reduce cataract severity and increase transparency in dissected rabbit cataractous lenses in vitro and cataract severity in vivo in dogs. Our study identifies lanosterol as a key molecule in the prevention of lens protein aggregation and points to a novel strategy for cataract prevention and treatment.


Assuntos
Catarata/tratamento farmacológico , Catarata/metabolismo , Lanosterol/farmacologia , Lanosterol/uso terapêutico , Agregados Proteicos/efeitos dos fármacos , Agregação Patológica de Proteínas/tratamento farmacológico , Adulto , Sequência de Aminoácidos , Amiloide/química , Amiloide/efeitos dos fármacos , Amiloide/metabolismo , Amiloide/ultraestrutura , Animais , Sequência de Bases , Catarata/congênito , Catarata/genética , Catarata/patologia , Linhagem Celular , Criança , Cristalinas/química , Cristalinas/genética , Cristalinas/metabolismo , Cristalinas/ultraestrutura , Cães , Feminino , Humanos , Lanosterol/administração & dosagem , Cristalino/efeitos dos fármacos , Cristalino/metabolismo , Cristalino/patologia , Masculino , Modelos Moleculares , Dados de Sequência Molecular , Proteínas Mutantes/química , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Proteínas Mutantes/ultraestrutura , Linhagem , Agregação Patológica de Proteínas/patologia
14.
J Virol ; 93(2)2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30355680

RESUMO

The hemagglutinin (HA), a glycoprotein on the surface of influenza A virus (IAV), initiates the virus life cycle by binding to terminal sialic acid (SA) residues on host cells. The HA gradually accumulates amino acid substitutions that allow IAV to escape immunity through a mechanism known as antigenic drift. We recently confirmed that a small set of amino acid residues are largely responsible for driving antigenic drift in swine-origin H3 IAV. All identified residues are located adjacent to the HA receptor binding site (RBS), suggesting that substitutions associated with antigenic drift may also influence receptor binding. Among those substitutions, residue 145 was shown to be a major determinant of antigenic evolution. To determine whether there are functional constraints to substitutions near the RBS and their impact on receptor binding and antigenic properties, we carried out site-directed mutagenesis experiments at the single-amino-acid level. We generated a panel of viruses carrying substitutions at residue 145 representing all 20 amino acids. Despite limited amino acid usage in nature, most substitutions at residue 145 were well tolerated without having a major impact on virus replication in vitro All substitution mutants retained receptor binding specificity, but the substitutions frequently led to decreased receptor binding. Glycan microarray analysis showed that substitutions at residue 145 modulate binding to a broad range of glycans. Furthermore, antigenic characterization identified specific substitutions at residue 145 that altered antibody recognition. This work provides a better understanding of the functional effects of amino acid substitutions near the RBS and the interplay between receptor binding and antigenic drift.IMPORTANCE The complex and continuous antigenic evolution of IAVs remains a major hurdle for vaccine selection and effective vaccination. On the hemagglutinin (HA) of the H3N2 IAVs, the amino acid substitution N 145 K causes significant antigenic changes. We show that amino acid 145 displays remarkable amino acid plasticity in vitro, tolerating multiple amino acid substitutions, many of which have not yet been observed in nature. Mutant viruses carrying substitutions at residue 145 showed no major impairment in virus replication in the presence of lower receptor binding avidity. However, their antigenic characterization confirmed the impact of the 145 K substitution in antibody immunodominance. We provide a better understanding of the functional effects of amino acid substitutions implicated in antigenic drift and its consequences for receptor binding and antigenicity. The mutation analyses presented in this report represent a significant data set to aid and test the ability of computational approaches to predict binding of glycans and in antigenic cartography analyses.


Assuntos
Substituição de Aminoácidos , Hemaglutininas Virais/química , Hemaglutininas Virais/metabolismo , Vírus da Influenza A/fisiologia , Suínos/virologia , Animais , Anticorpos Antivirais/metabolismo , Sítios de Ligação , Cães , Deriva Genética , Células HEK293 , Hemaglutininas Virais/genética , Humanos , Vírus da Influenza A/genética , Células Madin Darby de Rim Canino , Modelos Moleculares , Mutagênese Sítio-Dirigida , Polissacarídeos/metabolismo , Ligação Proteica , Replicação Viral
15.
Am J Kidney Dis ; 75(1): 124-137, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31358311

RESUMO

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a group of disorders characterized by inflammation and destruction of small- and medium-sized blood vessels and the presence of circulating ANCA. Clinical disease phenotypes include granulomatosis with polyangiitis, microscopic polyangiitis, eosinophilic granulomatosis with polyangiitis, and renal-limited vasculitis. Serologic classification of AAV into proteinase 3-ANCA disease and myeloperoxidase-ANCA disease correlates with a number of disease characteristics. AAV has a predilection for the kidney, with >75% of patients having renal involvement characterized by rapidly progressive glomerulonephritis. The cause and pathogenesis of AAV are multifactorial and influenced by genetics, environmental factors, and responses of the innate and adaptive immune system. Randomized controlled trials in the past 2 decades have refined the therapy of AAV and transformed AAV from a fatal disease to a chronic illness with relapsing course and associated morbidity. This article in AJKD's Core Curriculum in Nephrology series provides a detailed review of the epidemiology, pathogenesis, diagnosis, and advances in the management of AAV.


Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/terapia , Glomerulonefrite/terapia , Glucocorticoides/uso terapêutico , Imunossupressores/uso terapêutico , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/genética , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/imunologia , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/patologia , Anticorpos Anticitoplasma de Neutrófilos/imunologia , Síndrome de Churg-Strauss/genética , Síndrome de Churg-Strauss/imunologia , Síndrome de Churg-Strauss/patologia , Síndrome de Churg-Strauss/terapia , Ciclofosfamida/uso terapêutico , Progressão da Doença , Glomerulonefrite/genética , Glomerulonefrite/imunologia , Glomerulonefrite/patologia , Granulomatose com Poliangiite/genética , Granulomatose com Poliangiite/imunologia , Granulomatose com Poliangiite/patologia , Granulomatose com Poliangiite/terapia , Humanos , Transplante de Rim , Poliangiite Microscópica/genética , Poliangiite Microscópica/imunologia , Poliangiite Microscópica/patologia , Poliangiite Microscópica/terapia , Ácido Micofenólico/uso terapêutico , Mieloblastina/imunologia , Peroxidase/imunologia , Indução de Remissão , Diálise Renal , Rituximab/uso terapêutico
16.
J Virol ; 91(12)2017 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-28381580

RESUMO

Influenza B virus (IBV) is considered a major human pathogen, responsible for seasonal epidemics of acute respiratory illness. Two antigenically distinct IBV hemagglutinin (HA) lineages cocirculate worldwide with little cross-reactivity. Live attenuated influenza virus (LAIV) vaccines have been shown to provide better cross-protective immune responses than inactivated vaccines by eliciting local mucosal immunity and systemic B cell- and T cell-mediated memory responses. We have shown previously that incorporation of temperature-sensitive (ts) mutations into the PB1 and PB2 subunits along with a modified HA epitope tag in the C terminus of PB1 resulted in influenza A viruses (IAV) that are safe and effective as modified live attenuated (att) virus vaccines (IAV att). We explored whether analogous mutations in the IBV polymerase subunits would result in a stable virus with an att phenotype. The PB1 subunit of the influenza B/Brisbane/60/2008 strain was used to incorporate ts mutations and a C-terminal HA tag. Such modifications resulted in a B/Bris att strain with ts characteristics in vitro and an att phenotype in vivo Vaccination studies in mice showed that a single dose of the B/Bris att candidate stimulated sterilizing immunity against lethal homologous challenge and complete protection against heterologous challenge. These studies show the potential of an alternative LAIV platform for the development of IBV vaccines.IMPORTANCE A number of issues with regard to the effectiveness of the LAIV vaccine licensed in the United States (FluMist) have arisen over the past three seasons (2013-2014, 2014-2015, and 2015-2016). While the reasons for the limited robustness of the vaccine-elicited immune response remain controversial, this problem highlights the critical importance of continued investment in LAIV development and creates an opportunity to improve current strategies so as to develop more efficacious vaccines. Our laboratory has developed an alternative strategy, the incorporation of 2 amino acid mutations and a modified HA tag at the C terminus of PB1, which is sufficient to attenuate the IBV. As a LAIV, this novel vaccine provides complete protection against IBV strains. The availability of attenuated IAV and IBV backbones based on contemporary strains offers alternative platforms for the development of LAIVs that may overcome current limitations.


Assuntos
Vírus da Influenza B/imunologia , Vacinas contra Influenza/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Aminoácidos/genética , Animais , Variação Antigênica/genética , Variação Antigênica/imunologia , Genoma Viral , Humanos , Imunidade Humoral , Vírus da Influenza B/enzimologia , Vacinas contra Influenza/genética , Influenza Humana/imunologia , Influenza Humana/prevenção & controle , Influenza Humana/virologia , Pulmão/patologia , Pulmão/virologia , Camundongos , Mutação , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/virologia , Linfócitos T/imunologia , Vacinas Atenuadas/imunologia , Vacinas de Produtos Inativados/imunologia
17.
Neuroophthalmology ; 42(1): 49-51, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29467810

RESUMO

Brown syndrome is characterised by impaired supraduction worse in adduction due to a restricted superior oblique tendon passing through the trochlea. A few reports have previously described Brown syndrome after upper eyelid surgery, including blepharoplasty and ptosis repair. The authors describe two additional cases of Brown syndrome following ptosis repair. The first case is a 65-year-old woman with new-onset vertical binocular diplopia following bilateral levator advancement surgery. Ocular motility examination demonstrated moderate impairment of elevation in adduction. The second case is a 35-year-old woman who presented with new-onset intermittent binocular diplopia following right upper lid ptosis repair. Examination revealed large vertical fusional amplitudes and a large left intermittent hyperphoria in an alignment pattern consistent with Brown syndrome. Despite presenting after surgery, these cases differ in mechanism. The first case likely occurred due to intraoperative impairment of the superior oblique tendon sheath or trochlea, whereas the second case represented an unmasking of a long-standing, previous vertical strabismus that was consistent with a Brown syndrome pattern.

18.
Kidney Int ; 91(6): 1464-1472, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28233609

RESUMO

In the absence of uncontrolled hypertension or renal insufficiency, many consider the perinatal outcomes in pregnant women with nephrotic syndrome to be good. To further investigate this we performed a retrospective chart review of women with biopsy-proven nephrotic syndrome due to primary glomerular disease during pregnancy at a single tertiary center. Our review determined characteristics, presentation, management, pathologic diagnoses, and associated renal and maternal-fetal outcomes of 19 individuals with 26 pregnancies and 26 offspring. The mean age was 27.6 years, the mean gestational age at the presentation of nephrotic syndrome was 18.6 weeks, the mean creatinine was 0.85 mg/dL, mean serum albumin was 1.98 g/dL, and the mean proteinuria was 8.33 g/24 hours. The mean cardiac output was 8.6 L/minute, which was elevated compared to normal pregnancy. A kidney biopsy was performed during pregnancy in 8 individuals (median gestational age at time of biopsy was 21 weeks), changing management in six. Of the 26 pregnancies, maternal complications included preeclampsia in seven, acute kidney injury in six, premature rupture of membranes in two, and cellulitis in three. The mean age of gestation at delivery was 35.5 weeks. Fetal complications included low birth weight (under 2,500 g) in 14, intra-uterine growth restriction in three, and neonatal intensive care unit admission in eight. Thus, pregnant women with nephrotic syndrome are at high risk for developing both maternal and fetal complications, even in the absence of significant renal impairment or uncontrolled hypertension at the time of presentation of nephrotic syndrome.


Assuntos
Rim/fisiopatologia , Síndrome Nefrótica/complicações , Complicações na Gravidez/etiologia , Adulto , Biomarcadores/sangue , Biópsia , Pressão Sanguínea , Creatinina/sangue , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Rim/patologia , Síndrome Nefrótica/diagnóstico , Síndrome Nefrótica/fisiopatologia , Síndrome Nefrótica/terapia , Gravidez , Complicações na Gravidez/diagnóstico , Complicações na Gravidez/fisiopatologia , Complicações na Gravidez/terapia , Resultado da Gravidez , Estudos Retrospectivos , Fatores de Risco , Centros de Atenção Terciária , Resultado do Tratamento , Washington , Adulto Jovem
19.
Anal Biochem ; 537: 60-62, 2017 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-28867502

RESUMO

Fly fruit Drosophila melanogaster (DM) has been extensively employed as an in vivo model system to study pesticides toxicity. Pesticide administration to the fly traditionally involves feeding in an agar-gelled feed fly's medium (AM). However, AM method has several limitations such as uncertainty regarding the bioavailability and amount of pesticides ingested. And also high manipulation of the treated flies. We developed a new method of exposure the flies to pesticides, called Continuous Liquid Feeding (CLF). This method successfully delivers food to the flies at much higher concentrations than the AM method, and requires little manipulation of flies under treatment.


Assuntos
Drosophila melanogaster/efeitos dos fármacos , Métodos de Alimentação , Praguicidas/toxicidade , Ágar/química , Animais , Drosophila melanogaster/fisiologia , Ingestão de Alimentos , Feminino , Glicina/análogos & derivados , Glicina/toxicidade , Locomoção/efeitos dos fármacos , Masculino , Glifosato
20.
J Synchrotron Radiat ; 23(Pt 6): 1440-1446, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27787250

RESUMO

Photonic glass is a material class that can be used as photonic broadband reflectors, for example in the infrared regime as thermal barrier coating films. Photonic properties such as the reflectivity depend on the ordering and material packing fraction over the complete film thickness of up to 100 µm. Nanotomography allows acquiring these key parameters throughout the sample volume at the required resolution in a non-destructive way. By performing a nanotomography measurement at the PETRA III beamline P05 on a photonic glass film, the packing fraction throughout the complete sample thickness was analyzed. The results showed a packing fraction significantly smaller than the expected random close packing giving important information for improving the fabrication and processing methods of photonic glass material in the future.

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