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1.
PLoS Pathog ; 18(6): e1010573, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35679349

RESUMO

Powassan virus (POWV) is an emerging tick borne flavivirus (TBFV) that causes severe neuroinvasive disease. Currently, there are no approved treatments or vaccines to combat POWV infection. Here, we generated and characterized a nanoparticle immunogen displaying domain III (EDIII) of the POWV E glycoprotein. Immunization with POWV EDIII presented on nanoparticles resulted in significantly higher serum neutralizing titers against POWV than immunization with monomeric POWV EDIII. Furthermore, passive transfer of EDIII-reactive sera protected against POWV challenge in vivo. We isolated and characterized a panel of EDIII-specific monoclonal antibodies (mAbs) and identified several that potently inhibit POWV infection and engage distinct epitopes within the lateral ridge and C-C' loop of the EDIII. By creating a subunit-based nanoparticle immunogen with vaccine potential that elicits antibodies with protective activity against POWV infection, our findings enhance our understanding of the molecular determinants of antibody-mediated neutralization of TBFVs.


Assuntos
Vírus da Encefalite Transmitidos por Carrapatos , Nanopartículas , Animais , Anticorpos Monoclonais , Anticorpos Neutralizantes , Anticorpos Antivirais , Epitopos , Camundongos
2.
Clin Anat ; 35(7): 927-933, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35462436

RESUMO

The interosseous crural nerve (IOCn) is said to arise distally from muscular branches of the tibial nerve innervating the deep muscles of the posterior compartment of the leg. Here, we present the results of a cadaveric study of the IOCn to clarify this nerve's morphology and to discuss its potential clinical relevance. On 26 sides from 13 cadaveric specimens, the IOCn was dissected. The IOCn was identified on 14 out of 26 sides (53.8%). The mean diameter and length of the IOCn were 0.46 mm (range 0.3-0.72 mm) and 20.9 mm (range 13.5-33.0 mm), respectively. The origin of the IOCn was from a branch to the popliteus muscle on all sides. The nerve was found to have vascular, muscular, and ligamentous branches. In 53.8%, the nerve reached the inferior tibiofibular joint, and in 46.2%, the nerve terminated in the interosseous membrane of the leg. At its distal part, the IOCn gave off multiple vascular branches to the fibular artery. On one side (7.1%), the nerve pierced the interosseous membrane and innervated muscles of the anterior compartment of the leg. We believe this to be the first anatomical study of the IOCn. The nerve was found to have vascular, muscular, and ligamentous branches. Surgeons operating in the deep posterior compartment of the leg and ankle and clinicians treating patients with unusual presentations or pathology of the leg and ankle should be aware of this structure.


Assuntos
Perna (Membro) , Nervo Tibial , Cadáver , Humanos , Perna (Membro)/inervação , Músculo Esquelético/inervação , Nervo Tibial/anatomia & histologia
3.
Cell Chem Biol ; 29(5): 811-823.e7, 2022 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-35231399

RESUMO

Zika virus (ZIKV) is a flavivirus that can cause severe disease, but there are no approved treatments or vaccines. A complication for flavivirus vaccine development is the potential of immunogens to enhance infection via antibody-dependent enhancement (ADE), a process mediated by poorly neutralizing and cross-reactive antibodies. Thus, there is a great need to develop immunogens that minimize the potential to elicit enhancing antibodies. Here we utilized structure-based protein engineering to develop "resurfaced" (rs) ZIKV immunogens based on E glycoprotein domain III (ZDIIIs), in which epitopes bound by variably neutralizing antibodies were masked by combinatorial mutagenesis. We identified one resurfaced ZDIII immunogen (rsZDIII-2.39) that elicited a protective but immune-focused response. Compared to wild type ZDIII, immunization with resurfaced rsZDIII-2.39 protein nanoparticles produced fewer numbers of ZIKV EDIII antigen-reactive B cells and elicited serum that had a lower magnitude of induced ADE against dengue virus serotype 1 (DENV1) Our findings enhance our understanding of the structural and functional determinants of antibody protection against ZIKV.


Assuntos
Vírus da Dengue , Nanopartículas , Infecção por Zika virus , Zika virus , Anticorpos Neutralizantes , Anticorpos Antivirais , Vírus da Dengue/química , Humanos , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/genética , Infecção por Zika virus/prevenção & controle
4.
PLoS Comput Biol ; 18(1): e1009778, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35041647

RESUMO

The clinical outcome of SARS-CoV-2 infection varies widely between individuals. Machine learning models can support decision making in healthcare by assessing fatality risk in patients that do not yet show severe signs of COVID-19. Most predictive models rely on static demographic features and clinical values obtained upon hospitalization. However, time-dependent biomarkers associated with COVID-19 severity, such as antibody titers, can substantially contribute to the development of more accurate outcome models. Here we show that models trained on immune biomarkers, longitudinally monitored throughout hospitalization, predicted mortality and were more accurate than models based on demographic and clinical data upon hospital admission. Our best-performing predictive models were based on the temporal analysis of anti-SARS-CoV-2 Spike IgG titers, white blood cell (WBC), neutrophil and lymphocyte counts. These biomarkers, together with C-reactive protein and blood urea nitrogen levels, were found to correlate with severity of disease and mortality in a time-dependent manner. Shapley additive explanations of our model revealed the higher predictive value of day post-symptom onset (PSO) as hospitalization progresses and showed how immune biomarkers contribute to predict mortality. In sum, we demonstrate that the kinetics of immune biomarkers can inform clinical models to serve as a powerful monitoring tool for predicting fatality risk in hospitalized COVID-19 patients, underscoring the importance of contextualizing clinical parameters according to their time post-symptom onset.


Assuntos
Anticorpos Antivirais/sangue , COVID-19 , SARS-CoV-2/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , COVID-19/diagnóstico , COVID-19/epidemiologia , COVID-19/imunologia , COVID-19/terapia , Biologia Computacional , Diagnóstico por Computador , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Glicoproteína da Espícula de Coronavírus/imunologia , Adulto Jovem
5.
mBio ; 12(5): e0247321, 2021 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-34607456

RESUMO

Most known SARS-CoV-2 neutralizing antibodies (nAbs), including those approved by the FDA for emergency use, inhibit viral infection by targeting the receptor-binding domain (RBD) of the spike (S) protein. Variants of concern (VOC) carrying mutations in the RBD or other regions of S reduce the effectiveness of many nAbs and vaccines by evading neutralization. Therefore, therapies that are less susceptible to resistance are urgently needed. Here, we characterized the memory B-cell repertoire of COVID-19 convalescent donors and analyzed their RBD and non-RBD nAbs. We found that many of the non-RBD-targeting nAbs were specific to the N-terminal domain (NTD). Using neutralization assays with authentic SARS-CoV-2 and a recombinant vesicular stomatitis virus carrying SARS-CoV-2 S protein (rVSV-SARS2), we defined a panel of potent RBD and NTD nAbs. Next, we used a combination of neutralization-escape rVSV-SARS2 mutants and a yeast display library of RBD mutants to map their epitopes. The most potent RBD nAb competed with hACE2 binding and targeted an epitope that includes residue F490. The most potent NTD nAb epitope included Y145, K150, and W152. As seen with some of the natural VOC, the neutralization potencies of COVID-19 convalescent-phase sera were reduced by 4- to 16-fold against rVSV-SARS2 bearing Y145D, K150E, or W152R spike mutations. Moreover, we found that combining RBD and NTD nAbs did not enhance their neutralization potential. Notably, the same combination of RBD and NTD nAbs limited the development of neutralization-escape mutants in vitro, suggesting such a strategy may have higher efficacy and utility for mitigating the emergence of VOC. IMPORTANCE The U.S. FDA has issued emergency use authorizations (EUAs) for multiple investigational monoclonal antibody (MAb) therapies for the treatment of mild to moderate COVID-19. These MAb therapeutics are solely targeting the receptor-binding domain of the SARS-CoV-2 spike protein. However, the N-terminal domain of the spike protein also carries crucial neutralizing epitopes. Here, we show that key mutations in the N-terminal domain can reduce the neutralizing capacity of convalescent-phase COVID-19 sera. We report that a combination of two neutralizing antibodies targeting the receptor-binding and N-terminal domains may be beneficial to combat the emergence of virus variants.


Assuntos
Anticorpos Neutralizantes/imunologia , COVID-19/genética , COVID-19/imunologia , Mutação/imunologia , Motivos de Ligação ao RNA/imunologia , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Humanos , Testes de Neutralização
6.
Arch Pathol Lab Med ; 145(8): 929-936, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-33821952

RESUMO

CONTEXT.­: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) immunoglobulin G (IgG) testing is used for serosurveillance and will be important to evaluate vaccination status. Given the urgency to release coronavirus disease 2019 (COVID-19) serology tests, most manufacturers have developed qualitative tests. OBJECTIVE.­: To evaluate clinical performance of 6 different SARS-CoV-2 IgG assays and their quantitative results to better elucidate the clinical role of serology testing in COVID-19. DESIGN.­: Six SARS-CoV-2 IgG assays were tested using remnant specimens from 190 patients. Sensitivity and specificity were evaluated for each assay with the current manufacturer's cutoff and a lower cutoff. A numeric result analysis and discrepancy analysis were performed. RESULTS.­: Specificity was higher than 93% for all assays, and sensitivity was higher than 80% for all assays (≥7 days post-polymerase chain reaction testing). Inpatients with more severe disease had higher numeric values compared with health care workers with mild or moderate disease. Several discrepant serology results were those just below the manufacturers' cutoff. CONCLUSIONS.­: Severe acute respiratory syndrome coronavirus 2 IgG antibody testing can aid in the diagnosis of COVID-19, especially with negative polymerase chain reaction. Quantitative COVID-19 IgG results are important to better understand the immunologic response and disease course of this novel virus and to assess immunity as part of future vaccination programs.


Assuntos
Anticorpos Antivirais/sangue , Teste Sorológico para COVID-19/métodos , COVID-19/imunologia , Imunoglobulina G/sangue , SARS-CoV-2/imunologia , COVID-19/diagnóstico , COVID-19/epidemiologia , Teste de Ácido Nucleico para COVID-19/estatística & dados numéricos , Teste Sorológico para COVID-19/estatística & dados numéricos , Estudos de Coortes , Humanos , Cidade de Nova Iorque/epidemiologia , Pandemias , Sensibilidade e Especificidade , Índice de Gravidade de Doença
7.
mSphere ; 6(2)2021 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-33883259

RESUMO

The coronavirus disease 2019 (COVID-19) global pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to place an immense burden on societies and health care systems. A key component of COVID-19 control efforts is serological testing to determine the community prevalence of SARS-CoV-2 exposure and quantify individual immune responses to prior SARS-CoV-2 infection or vaccination. Here, we describe a laboratory-developed antibody test that uses readily available research-grade reagents to detect SARS-CoV-2 exposure in patient blood samples with high sensitivity and specificity. We further show that this sensitive test affords the estimation of viral spike-specific IgG titers from a single sample measurement, thereby providing a simple and scalable method to measure the strength of an individual's immune response. The accuracy, adaptability, and cost-effectiveness of this test make it an excellent option for clinical deployment in the ongoing COVID-19 pandemic.IMPORTANCE Serological surveillance has become an important public health tool during the COVID-19 pandemic. Detection of protective antibodies and seroconversion after SARS-CoV-2 infection or vaccination can help guide patient care plans and public health policies. Serology tests can detect antibodies against past infections; consequently, they can help overcome the shortcomings of molecular tests, which can detect only active infections. This is important, especially when considering that many COVID-19 patients are asymptomatic. In this study, we describe an enzyme-linked immunosorbent assay (ELISA)-based qualitative and quantitative serology test developed to measure IgG and IgA antibodies against the SARS-CoV-2 spike glycoprotein. The test can be deployed using commonly available laboratory reagents and equipment and displays high specificity and sensitivity. Furthermore, we demonstrate that IgG titers in patient samples can be estimated from a single measurement, enabling the assay's use in high-throughput clinical environments.


Assuntos
Anticorpos Antivirais/sangue , Teste Sorológico para COVID-19/métodos , COVID-19/diagnóstico , COVID-19/imunologia , SARS-CoV-2/imunologia , Adolescente , Adulto , Idoso , Especificidade de Anticorpos , COVID-19/epidemiologia , Teste Sorológico para COVID-19/estatística & dados numéricos , Estudos de Casos e Controles , Estudos de Coortes , Ensaio de Imunoadsorção Enzimática/métodos , Ensaio de Imunoadsorção Enzimática/estatística & dados numéricos , Monitoramento Epidemiológico , Feminino , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Pandemias , Estudos Soroepidemiológicos , Glicoproteína da Espícula de Coronavírus/imunologia , Adulto Jovem
8.
JCI Insight ; 6(4)2021 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-33476300

RESUMO

Convalescent plasma with severe acute respiratory disease coronavirus 2 (SARS-CoV-2) antibodies (CCP) may hold promise as a treatment for coronavirus disease 2019 (COVID-19). We compared the mortality and clinical outcome of patients with COVID-19 who received 200 mL of CCP with a spike protein IgG titer ≥ 1:2430 (median 1:47,385) within 72 hours of admission with propensity score-matched controls cared for at a medical center in the Bronx, between April 13 and May 4, 2020. Matching criteria for controls were age, sex, body mass index, race, ethnicity, comorbidities, week of admission, oxygen requirement, D-dimer, lymphocyte counts, corticosteroid use, and anticoagulation use. There was no difference in mortality or oxygenation between CCP recipients and controls at day 28. When stratified by age, compared with matched controls, CCP recipients less than 65 years had 4-fold lower risk of mortality and 4-fold lower risk of deterioration in oxygenation or mortality at day 28. For CCP recipients, pretransfusion spike protein IgG, IgM, and IgA titers were associated with mortality at day 28 in univariate analyses. No adverse effects of CCP were observed. Our results suggest CCP may be beneficial for hospitalized patients less than 65 years, but data from controlled trials are needed to validate this finding and establish the effect of aging on CCP efficacy.


Assuntos
Anticorpos Neutralizantes/administração & dosagem , Anticorpos Antivirais/administração & dosagem , COVID-19/terapia , SARS-CoV-2/imunologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , COVID-19/imunologia , COVID-19/mortalidade , COVID-19/virologia , Feminino , Mortalidade Hospitalar , Humanos , Imunização Passiva/métodos , Masculino , Pessoa de Meia-Idade , Cidade de Nova Iorque/epidemiologia , Pontuação de Propensão , Estudos Retrospectivos , Glicoproteína da Espícula de Coronavírus/imunologia , Resultado do Tratamento , Soroterapia para COVID-19
9.
ACS Omega ; 6(1): 85-102, 2021 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-33458462

RESUMO

Coronavirus disease 2019 (COVID-19) is a global health crisis caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and there is a critical need to produce large quantities of high-quality SARS-CoV-2 Spike (S) protein for use in both clinical and basic science settings. To address this need, we have evaluated the expression and purification of two previously reported S protein constructs in Expi293F and ExpiCHO-S cells, two different cell lines selected for increased protein expression. We show that ExpiCHO-S cells produce enhanced yields of both SARS-CoV-2 S proteins. Biochemical, biophysical, and structural (cryo-EM) characterizations of the SARS-CoV-2 S proteins produced in both cell lines demonstrate that the reported purification strategy yields high-quality S protein (nonaggregated, uniform material with appropriate biochemical and biophysical properties), and analysis of 20 deposited S protein cryo-EM structures reveals conformation plasticity in the region composed of amino acids 614-642 and 828-854. Importantly, we show that multiple preparations of these two recombinant S proteins from either cell line exhibit identical behavior in two different serology assays. We also evaluate the specificity of S protein-mediated host cell binding by examining interactions with proposed binding partners in the human secretome and report no novel binding partners and notably fail to validate the Spike:CD147 interaction. In addition, the antigenicity of these proteins is demonstrated by standard ELISAs and in a flexible protein microarray format. Collectively, we establish an array of metrics for ensuring the production of high-quality S protein to support clinical, biological, biochemical, structural, and mechanistic studies to combat the global pandemic caused by SARS-CoV-2.

10.
medRxiv ; 2020 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-33300012

RESUMO

Convalescent plasma with severe acute respiratory disease coronavirus 2 (SARS-CoV-2) antibodies (CCP) may hold promise as treatment for Coronavirus Disease 2019 (COVID-19). We compared the mortality and clinical outcome of patients with COVID-19 who received 200mL of CCP with a Spike protein IgG titer ≥1:2,430 (median 1:47,385) within 72 hours of admission to propensity score-matched controls cared for at a medical center in the Bronx, between April 13 to May 4, 2020. Matching criteria for controls were age, sex, body mass index, race, ethnicity, comorbidities, week of admission, oxygen requirement, D-dimer, lymphocyte counts, corticosteroids, and anticoagulation use. There was no difference in mortality or oxygenation between CCP recipients and controls at day 28. When stratified by age, compared to matched controls, CCP recipients <65 years had 4-fold lower mortality and 4-fold lower deterioration in oxygenation or mortality at day 28. For CCP recipients, pre-transfusion Spike protein IgG, IgM and IgA titers were associated with mortality at day 28 in univariate analyses. No adverse effects of CCP were observed. Our results suggest CCP may be beneficial for hospitalized patients <65 years, but data from controlled trials is needed to validate this finding and establish the effect of ageing on CCP efficacy.

11.
medRxiv ; 2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32935116

RESUMO

The COVID-19 global pandemic caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) continues to place an immense burden on societies and healthcare systems. A key component of COVID-19 control efforts is serologic testing to determine the community prevalence of SARS-CoV-2 exposure and quantify individual immune responses to prior infection or vaccination. Here, we describe a laboratory-developed antibody test that uses readily available research-grade reagents to detect SARS-CoV-2 exposure in patient blood samples with high sensitivity and specificity. We further show that this test affords the estimation of viral spike-specific IgG titers from a single sample measurement, thereby providing a simple and scalable method to measure the strength of an individual's immune response. The accuracy, adaptability, and cost-effectiveness of this test makes it an excellent option for clinical deployment in the ongoing COVID-19 pandemic.

12.
Cell Host Microbe ; 28(3): 486-496.e6, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32738193

RESUMO

There is an urgent need for vaccines and therapeutics to prevent and treat COVID-19. Rapid SARS-CoV-2 countermeasure development is contingent on the availability of robust, scalable, and readily deployable surrogate viral assays to screen antiviral humoral responses, define correlates of immune protection, and down-select candidate antivirals. Here, we generate a highly infectious recombinant vesicular stomatitis virus (VSV) bearing the SARS-CoV-2 spike glycoprotein S as its sole entry glycoprotein and show that this recombinant virus, rVSV-SARS-CoV-2 S, closely resembles SARS-CoV-2 in its entry-related properties. The neutralizing activities of a large panel of COVID-19 convalescent sera can be assessed in a high-throughput fluorescent reporter assay with rVSV-SARS-CoV-2 S, and neutralization of rVSV-SARS-CoV-2 S and authentic SARS-CoV-2 by spike-specific antibodies in these antisera is highly correlated. Our findings underscore the utility of rVSV-SARS-CoV-2 S for the development of spike-specific therapeutics and for mechanistic studies of viral entry and its inhibition.


Assuntos
Betacoronavirus/patogenicidade , Infecções por Coronavirus/virologia , Pneumonia Viral/virologia , Glicoproteína da Espícula de Coronavírus/fisiologia , Vírus da Estomatite Vesicular Indiana/fisiologia , Enzima de Conversão de Angiotensina 2 , Animais , Antivirais/farmacologia , Betacoronavirus/genética , Betacoronavirus/fisiologia , COVID-19 , Vacinas contra COVID-19 , Linhagem Celular , Chlorocebus aethiops , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/genética , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/terapia , Avaliação Pré-Clínica de Medicamentos , Interações entre Hospedeiro e Microrganismos/efeitos dos fármacos , Interações entre Hospedeiro e Microrganismos/genética , Interações entre Hospedeiro e Microrganismos/fisiologia , Humanos , Mutação , Testes de Neutralização , Pandemias/prevenção & controle , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/fisiologia , Pneumonia Viral/prevenção & controle , Pneumonia Viral/terapia , Receptores Virais/genética , Receptores Virais/fisiologia , Recombinação Genética , SARS-CoV-2 , Serina Endopeptidases/fisiologia , Glicoproteína da Espícula de Coronavírus/genética , Células Vero , Vírus da Estomatite Vesicular Indiana/genética , Vacinas Virais/genética , Vacinas Virais/imunologia , Internalização do Vírus , Replicação Viral/genética , Tratamento Farmacológico da COVID-19
13.
bioRxiv ; 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32511365

RESUMO

There is an urgent need for vaccines and therapeutics to prevent and treat COVID-19. Rapid SARS-CoV-2 countermeasure development is contingent on the availability of robust, scalable, and readily deployable surrogate viral assays to screen antiviral humoral responses, and define correlates of immune protection, and to down-select candidate antivirals. Here, we describe a highly infectious recombinant vesicular stomatitis virus bearing the SARS-CoV-2 spike glycoprotein S as its sole entry glycoprotein that closely resembles the authentic agent in its entry-related properties. We show that the neutralizing activities of a large panel of COVID-19 convalescent sera can be assessed in high-throughput fluorescent reporter assay with rVSV-SARS-CoV-2 S and that neutralization of the rVSV and authentic SARS-CoV-2 by spike-specific antibodies in these antisera is highly correlated. Our findings underscore the utility of rVSV-SARS-CoV-2 S for the development of spike-specific vaccines and therapeutics and for mechanistic studies of viral entry and its inhibition.

14.
bioRxiv ; 2020 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-32587972

RESUMO

Coronavirus disease 2019 ( COVID-19 ) is a global health crisis caused by the novel severe acute respiratory syndrome coronavirus 2 ( SARS-CoV-2 ), and there is a critical need to produce large quantities of high-quality SARS-CoV-2 Spike ( S ) protein for use in both clinical and basic science settings. To address this need, we have evaluated the expression and purification of two previously reported S protein constructs in Expi293F ™ and ExpiCHO-S ™ cells, two different cell lines selected for increased expression of secreted glycoproteins. We show that ExpiCHO-S ™ cells produce enhanced yields of both SARS-CoV-2 S proteins. Biochemical, biophysical, and structural ( cryo-EM ) characterization of the SARS-CoV-2 S proteins produced in both cell lines demonstrate that the reported purification strategy yields high quality S protein (non-aggregated, uniform material with appropriate biochemical and biophysical properties). Importantly, we show that multiple preparations of these two recombinant S proteins from either cell line exhibit identical behavior in two different serology assays. We also evaluate the specificity of S protein-mediated host cell binding by examining interactions with proposed binding partners in the human secretome. In addition, the antigenicity of these proteins is demonstrated by standard ELISAs, and in a flexible protein microarray format. Collectively, we establish an array of metrics for ensuring the production of high-quality S protein to support clinical, biological, biochemical, structural and mechanistic studies to combat the global pandemic caused by SARS-CoV-2.

15.
Blood Adv ; 3(23): 3962-3967, 2019 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-31805192

RESUMO

Therapy-related acute myeloid leukemia and myelodysplastic syndromes (t-AML/t-MDS) are secondary hematologic malignancies associated with poor prognosis, warranting insights into their predisposing conditions and cells of origin. We identified patients with myeloma who developed t-AML/t-MDS and analyzed their stem and progenitor cells collected years before the onset of secondary disease. We demonstrate that aberrant stem cells with high CD123 expression can be detected long before the onset of overt leukemia. Rigorous sorting, followed by targeted sequencing, resulted in ultradeep functional depth of sequencing and revealed preexisting mutant hematopoietic stem cell (HSC) clones, mainly harboring TP53 mutations, that became the dominant population at the time of leukemic presentation. Taken together, these data show that HSCs can act as reservoirs for leukemia-initiating cells many years before the onset of myeloid leukemia.


Assuntos
Células-Tronco Hematopoéticas/metabolismo , Leucemia Mieloide Aguda/etiologia , Mieloma Múltiplo/complicações , Segunda Neoplasia Primária/etiologia , Humanos , Leucemia Mieloide Aguda/patologia , Mieloma Múltiplo/patologia , Mutação , Segunda Neoplasia Primária/patologia
16.
Mol Imaging ; 17: 1536012118787322, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30039729

RESUMO

Reseeding of decellularized organ scaffolds with a patient's own cells has promise for eliminating graft versus host disease. This study investigated whether ultrasound imaging or magnetic resonance imaging (MRI) can track the reseeding of murine liver scaffolds with silica-labeled or iron-labeled liver hepatocytes. Mesoporous silica particles were created using the Stöber method, loaded with Alexa Flour 647 fluorophore, and conjugated with protamine sulfate, glutamine, and glycine. Fluorescent iron oxide particles were obtained from a commercial source. Liver cells from donor mice were loaded with the silica particles or iron oxide particles. Donor livers were decellularized and reperfused with silica-labeled or iron-labeled cells. The reseeded livers were longitudinally analyzed with ultrasound imaging and MRI. Liver biopsies were imaged with confocal microscopy and scanning electron microscopy. Ultrasound imaging had a detection limit of 0.28 mg/mL, while MRI had a lower detection limit of 0.08 mg/mL based on particle weight. The silica-loaded cells proliferated at a slower rate compared to iron-loaded cells. Ultrasound imaging, MRI, and confocal microscopy underestimated cell numbers relative to scanning electron microscopy. Ultrasound imaging had the greatest underestimation due to coarse resolution compared to the other imaging modalities. Despite this underestimation, both ultrasound imaging and MRI successfully tracked the longitudinal recellularization of liver scaffolds.


Assuntos
Compostos Férricos/química , Fígado/metabolismo , Dióxido de Silício/química , Animais , Fígado/citologia , Fígado/diagnóstico por imagem , Fígado/ultraestrutura , Imageamento por Ressonância Magnética , Camundongos SCID , Ultrassonografia
17.
Int J Nanomedicine ; 12: 6221-6238, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28894363

RESUMO

The purpose of the study was to investigate the stability and biopharmaceutical characteristics of ketoprofen, loaded in polymeric carriers, which were included into a bigel in a semisolid dosage form. The polymer carriers with in situ-included ketoprofen were obtained by emulsifier-free emulsion polymerization of the monomers in aqueous medium or a solution of the polymers used. The morphological characteristics of the carriers, the in vitro release and the photochemical stability of ketoprofen were evaluated. The model with optimal characteristics was included in a bigel formulation. The bigel was characterized in terms of pH, rheological behavior, spreadability, and in vitro drug release. Acute skin toxicity, antinociceptive activity, anti-inflammatory activity, and antihyperalgesic effects of the prepared bigel with ketoprofen-loaded polymer carrier were evaluated. The carriers of ketoprofen were characterized by a high yield and drug loading. The particle size distribution varied widely according to the polymer used, and a sustained release was provided for up to 6 hours. The polymer mixture poly(vinyl acetate) and hydroxypropyl cellulose as a drug carrier, alone or included in the bigel composition, improved the photostability of the drug compared with unprotected ketoprofen. The bigel with ketoprofen-loaded particles provided sustained release of the drug and had optimal rheological parameters. In vivo experiments on the bigel showed no skin inflammation or irritation. Four hours after its application, a well-defined analgesic, anti-inflammatory, and antihyperalgesic effect was registered. The polymer mixture of poly(vinyl acetate) and hydroxypropyl cellulose as a carrier of ketoprofen and the bigel in which it was included provided an enhanced photostability and sustained drug release.


Assuntos
Portadores de Fármacos/química , Cetoprofeno/química , Cetoprofeno/farmacocinética , Administração Tópica , Analgésicos/administração & dosagem , Analgésicos/farmacocinética , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/farmacocinética , Preparações de Ação Retardada/química , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Emulsões/química , Concentração de Íons de Hidrogênio , Cetoprofeno/administração & dosagem , Masculino , Tamanho da Partícula , Polímeros/química , Polivinil/química , Ratos Wistar , Reologia
18.
AAPS PharmSciTech ; 18(1): 166-174, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-26931442

RESUMO

Nowadays, the modern pharmaceutical investigations are directed toward obtaining of new polymer micro- and nano-sized drug delivery carriers. In this respect, the use of hydrogel carriers based on polyzwitterions (PZIs) is an opportunity in the preparation of polymer drug delivery systems with desired characteristics. This paper describes the synthesis and characterization of micro-structured p(VA-co-DMAPS) systems with different compositions in situ loaded with Ibuprofen by emulsifier-free emulsion copolymerization (EEC) in water. The mean size of the prepared microparticles was measured by SEM and particles have been visualized by AFM. The inclusion of Ibuprofen in the polyzwitterionic copolymer microgel systems was established by using DSC. In vitro drug release experiments were carried out in order to estimate the ability of the obtained microgels to modify the release of water-insoluble Ibuprofen.


Assuntos
Anti-Inflamatórios não Esteroides/química , Ibuprofeno/química , Polímeros/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Emulsões/química , Tamanho da Partícula , Água/química
19.
Mol Biosyst ; 11(5): 1370-7, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25813365

RESUMO

We analyzed the structural features of C1q that underlie its autoantigenicity by means of a model system using the amphiphilic polyzwitterion (PZ), poly(ethylene oxide-b-N,N-dimethyl(methacryloyloxyethyl) ammonium propanesulfonate) in the process of C1q immobilization. The source of anti-C1q autoantibodies was human sera from patients with Lupus Nephritis (LN). Both analyzed concentrations of PZ, 25 mM and 50 mM, were found to be applicable for inducing conformational transitions which resulted in increased recognition of C1q and the globular domain of its B polypeptide chain, designated ghB, by the LN autoantibodies. The registered conformational transitions displayed a hydrophobic enhancement of the protein microenvironment due to the presence of hydrophobic binding sites in ghB which consequently affected the autoantigenicity of the whole C1q molecule.


Assuntos
Autoantígenos/química , Autoantígenos/imunologia , Complemento C1q/química , Complemento C1q/imunologia , Interações Hidrofóbicas e Hidrofílicas , Conformação Proteica , Domínios e Motivos de Interação entre Proteínas/imunologia , Adulto , Idoso , Sequência de Aminoácidos , Autoanticorpos/sangue , Autoanticorpos/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Nefrite Lúpica/imunologia , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Ligação Proteica/imunologia , Subunidades Proteicas/química , Relação Estrutura-Atividade , Adulto Jovem
20.
J Diabetes Sci Technol ; 8(6): 1097-104, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25190081

RESUMO

We analyzed the pretransplant continuous glucose monitoring (CGM) data of 45 patients that underwent total pancreatectomy followed by autologous islet transplantation (AIT) at the University of Arizona Medical Center. Traditional and novel metrics of CGM time series were correlated to the total islet count (TIC), islet equivalents (IEQs), and weight-normalized IEQs (IEQ/kg). In a subset cohort (n = 26) we analyzed the relationship among the infused number of islets, the CGM indicators, and the first recorded insulin requirement after the procedure. We conclude that receiving a high islet yield is sufficient yet not necessary to achieve low or null insulin requirements within the first 50 days after surgery. Furthermore, CGM inertia and CGM length of curve (2 novel CGM indicators) are shown to be correlated to islet yield, and the CGMs normalized area (Ao) and time ratio above hyperglycemic level (To) are strongly correlated to insulin requirement. A screening test based on To is shown to have 100% sensitivity and 88% specificity discriminating insulin independence upon discharge.


Assuntos
Glicemia/análise , Transplante das Ilhotas Pancreáticas/métodos , Adulto , Automonitorização da Glicemia , Feminino , Humanos , Hipoglicemiantes/administração & dosagem , Insulina/administração & dosagem , Masculino , Pancreatectomia , Pancreatite Crônica/cirurgia , Transplante Autólogo , Resultado do Tratamento
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