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1.
Signal Transduct Target Ther ; 5(1): 219, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-33024082

RESUMO

Convalescent plasma (CP) transfusion has been indicated as a promising therapy in the treatment for other emerging viral infections. However, the quality control of CP and individual variation in patients in different studies make it rather difficult to evaluate the efficacy and risk of CP therapy for coronavirus disease 2019 (COVID-19). We aimed to explore the potential efficacy of CP therapy, and to assess the possible factors associated with its efficacy. We enrolled eight critical or severe COVID-19 patients from four centers. Each patient was transfused with 200-400 mL of CP from seven recovered donors. The primary indicators for clinical efficacy assessment were the changes of clinical symptoms, laboratory parameters, and radiological image after CP transfusion. CP donors had a wide range of antibody levels measured by serology tests which were to some degree correlated with the neutralizing antibody (NAb) level. No adverse events were observed during and after CP transfusion. Following CP transfusion, six out of eight patients showed improved oxygen support status; chest CT indicated varying degrees of absorption of pulmonary lesions in six patients within 8 days; the viral load was decreased to a negative level in five patients who had the previous viremia; other laboratory parameters also tended to improve, including increased lymphocyte counts, decreased C-reactive protein, procalcitonin, and indicators for liver function. The clinical efficacy might be associated with CP transfusion time, transfused dose, and the NAb levels of CP. This study indicated that CP might be a potential therapy for severe patients with COVID-19.


Assuntos
Anticorpos Neutralizantes/administração & dosagem , Anticorpos Antivirais/administração & dosagem , Betacoronavirus/patogenicidade , Infecções por Coronavirus/terapia , Pneumonia Viral/terapia , Adulto , Idoso , Antivirais/uso terapêutico , Betacoronavirus/imunologia , Biomarcadores/sangue , Proteína C-Reativa/metabolismo , Técnicas de Laboratório Clínico , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/diagnóstico por imagem , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/patologia , Progressão da Doença , Feminino , Humanos , Imunização Passiva/métodos , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/diagnóstico por imagem , Pneumonia Viral/imunologia , Pneumonia Viral/patologia , Pró-Calcitonina/sangue , Índice de Gravidade de Doença , Tomografia Computadorizada por Raios X , Carga Viral
2.
Nat Microbiol ; 5(10): 1185-1191, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32908214

RESUMO

Antibody-based drugs and vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are being expedited through preclinical and clinical development. Data from the study of SARS-CoV and other respiratory viruses suggest that anti-SARS-CoV-2 antibodies could exacerbate COVID-19 through antibody-dependent enhancement (ADE). Previous respiratory syncytial virus and dengue virus vaccine studies revealed human clinical safety risks related to ADE, resulting in failed vaccine trials. Here, we describe key ADE mechanisms and discuss mitigation strategies for SARS-CoV-2 vaccines and therapies in development. We also outline recently published data to evaluate the risks and opportunities for antibody-based protection against SARS-CoV-2.


Assuntos
Anticorpos Facilitadores , Betacoronavirus , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/terapia , Pneumonia Viral/imunologia , Pneumonia Viral/terapia , Vacinas Virais/efeitos adversos , Animais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Neutralizantes/administração & dosagem , Anticorpos Antivirais/administração & dosagem , Anticorpos Antivirais/imunologia , Anticorpos Facilitadores/imunologia , Betacoronavirus/imunologia , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/prevenção & controle , Humanos , Imunização Passiva/efeitos adversos , Técnicas In Vitro , Modelos Imunológicos , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Doenças Respiratórias/etiologia , Doenças Respiratórias/imunologia , Fatores de Risco , Segurança , Vacinas Virais/imunologia
3.
Front Immunol ; 11: 1660, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32760407

RESUMO

The current outbreak of viral pneumonia, caused by novel coronavirus SARS-CoV-2, is the focus of worldwide attention. The WHO declared the COVID-19 outbreak a pandemic event on Mar 12, 2020, and the number of confirmed cases is still on the rise worldwide. While most infected individuals only experience mild symptoms or may even be asymptomatic, some patients rapidly progress to severe acute respiratory failure with substantial mortality, making it imperative to develop an efficient treatment for severe SARS-CoV-2 pneumonia alongside supportive care. So far, the optimal treatment strategy for severe COVID-19 remains unknown. Intravenous immunoglobulin (IVIg) is a blood product pooled from healthy donors with high concentrations of immunoglobulin G (IgG) and has been used in patients with autoimmune and inflammatory diseases for more than 30 years. In this review, we aim to highlight the known mechanisms of immunomodulatory effects of high-dose IVIg therapy, the immunopathological hypothesis of viral pneumonia, and the clinical evidence of IVIg therapy in viral pneumonia. We then make cautious therapeutic inferences about high-dose IVIg therapy in treating severe COVID-19. These inferences may provide relevant and useful insights in order to aid treatment for COVID-19.


Assuntos
Anticorpos Neutralizantes/uso terapêutico , Betacoronavirus/imunologia , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/imunologia , Imunoglobulina G/uso terapêutico , Imunoglobulinas Intravenosas/uso terapêutico , Fatores Imunológicos/uso terapêutico , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/imunologia , Adulto , Animais , Anticorpos Neutralizantes/administração & dosagem , Anticorpos Facilitadores , Criança , Infecções por Coronavirus/virologia , Citocinas/metabolismo , Humanos , Fragmentos Fab das Imunoglobulinas/metabolismo , Fragmentos Fc das Imunoglobulinas/metabolismo , Imunoglobulina G/administração & dosagem , Imunoglobulinas Intravenosas/administração & dosagem , Fatores Imunológicos/administração & dosagem , Pandemias , Pneumonia Viral/virologia
4.
Nat Rev Immunol ; 20(10): 633-643, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32782358

RESUMO

Antibody-dependent enhancement (ADE) is a mechanism by which the pathogenesis of certain viral infections is enhanced in the presence of sub-neutralizing or cross-reactive non-neutralizing antiviral antibodies. In vitro modelling of ADE has attributed enhanced pathogenesis to Fcγ receptor (FcγR)-mediated viral entry, rather than canonical viral receptor-mediated entry. However, the putative FcγR-dependent mechanisms of ADE overlap with the role of these receptors in mediating antiviral protection in various viral infections, necessitating a detailed understanding of how this diverse family of receptors functions in protection and pathogenesis. Here, we discuss the diversity of immune responses mediated upon FcγR engagement and review the available experimental evidence supporting the role of FcγRs in antiviral protection and pathogenesis through ADE. We explore FcγR engagement in the context of a range of different viral infections, including dengue virus and SARS-CoV, and consider ADE in the context of the ongoing SARS-CoV-2 pandemic.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Anticorpos Antivirais/administração & dosagem , Anticorpos Facilitadores/efeitos dos fármacos , Betacoronavirus/efeitos dos fármacos , Infecções por Coronavirus/tratamento farmacológico , Leucócitos/efeitos dos fármacos , Pneumonia Viral/tratamento farmacológico , Receptores de IgG/imunologia , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais/biossíntese , Anticorpos Neutralizantes/administração & dosagem , Anticorpos Neutralizantes/efeitos adversos , Anticorpos Neutralizantes/biossíntese , Anticorpos Antivirais/efeitos adversos , Anticorpos Antivirais/biossíntese , Betacoronavirus/imunologia , Betacoronavirus/patogenicidade , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Dengue/tratamento farmacológico , Dengue/imunologia , Dengue/virologia , Vírus da Dengue/efeitos dos fármacos , Vírus da Dengue/imunologia , Vírus da Dengue/patogenicidade , Regulação da Expressão Gênica , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Interações Hospedeiro-Patógeno/imunologia , Humanos , Leucócitos/imunologia , Leucócitos/virologia , Pandemias , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , Receptores de IgG/antagonistas & inibidores , Receptores de IgG/genética , Vírus da SARS/efeitos dos fármacos , Vírus da SARS/imunologia , Vírus da SARS/patogenicidade , Síndrome Respiratória Aguda Grave/tratamento farmacológico , Síndrome Respiratória Aguda Grave/imunologia , Síndrome Respiratória Aguda Grave/virologia , Transdução de Sinais , Internalização do Vírus/efeitos dos fármacos
5.
Virol J ; 17(1): 80, 2020 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-32560646

RESUMO

BACKGROUND: Convalescent plasma (CP) transfusion was reported to be effective in treating critically ill patients with COVID-19, and hydroxychloroquine could potently inhibit SARS-CoV-2 in vitro. Herein, we reported a case receiving combination therapy with CP transfusion and hydroxychloroquine for the first time. CASE PRESENTATION: Laboratory findings showed high lactic acid level (2.1 mmol/L) and C-reactive protein (CRP, 48.8 mg/L), and low white blood cell count (1.96 × 109/L) in a 65-year-old Chinese man, who was diagnosed with severe COVID-19. CP was intravenously given twice, and hydroxychloroquine was orally administrated for a week (0.2 g, three times a day). The lactic acid and C-reactive protein levels remained high (2.1 mmol/L and 73.23 mg/L, respectively), while the arterial oxyhemoglobin saturation decreased to 86% with a low oxygenation index (OI, 76 mmHg) on day 4 after CP transfusion. His temperature returned to normal and the OI ascended above 300 on day 11. Moreover, the RNA test remained positive in throat swab, and computed tomography revealed severe pulmonary lesions on day 11 after admission. CONCLUSION: These findings suggested that the effectiveness of combination therapy with CP and hydroxychloroquine may be non-optimal, and specific therapy needs to be explored.


Assuntos
Transfusão de Componentes Sanguíneos/métodos , Infecções por Coronavirus/terapia , Hidroxicloroquina/administração & dosagem , Pneumonia Viral/terapia , Administração Oral , Idoso , Anticorpos Neutralizantes/administração & dosagem , Anticorpos Antivirais/administração & dosagem , Betacoronavirus/isolamento & purificação , Proteína C-Reativa/metabolismo , Infecções por Coronavirus/sangue , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Humanos , Imunização Passiva/métodos , Ácido Láctico/sangue , Contagem de Leucócitos , Masculino , Oxiemoglobinas , Pandemias , Pneumonia Viral/sangue , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/virologia , Carga Viral
6.
Cell ; 182(1): 73-84.e16, 2020 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-32425270

RESUMO

The COVID-19 pandemic urgently needs therapeutic and prophylactic interventions. Here, we report the rapid identification of SARS-CoV-2-neutralizing antibodies by high-throughput single-cell RNA and VDJ sequencing of antigen-enriched B cells from 60 convalescent patients. From 8,558 antigen-binding IgG1+ clonotypes, 14 potent neutralizing antibodies were identified, with the most potent one, BD-368-2, exhibiting an IC50 of 1.2 and 15 ng/mL against pseudotyped and authentic SARS-CoV-2, respectively. BD-368-2 also displayed strong therapeutic and prophylactic efficacy in SARS-CoV-2-infected hACE2-transgenic mice. Additionally, the 3.8 Å cryo-EM structure of a neutralizing antibody in complex with the spike-ectodomain trimer revealed the antibody's epitope overlaps with the ACE2 binding site. Moreover, we demonstrated that SARS-CoV-2-neutralizing antibodies could be directly selected based on similarities of their predicted CDR3H structures to those of SARS-CoV-neutralizing antibodies. Altogether, we showed that human neutralizing antibodies could be efficiently discovered by high-throughput single B cell sequencing in response to pandemic infectious diseases.


Assuntos
Anticorpos Monoclonais/isolamento & purificação , Anticorpos Neutralizantes/isolamento & purificação , Linfócitos B/imunologia , Infecções por Coronavirus/imunologia , Pneumonia Viral/imunologia , Análise de Célula Única , Animais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/química , Anticorpos Monoclonais/metabolismo , Anticorpos Neutralizantes/administração & dosagem , Anticorpos Neutralizantes/química , Anticorpos Neutralizantes/metabolismo , Convalescença , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Camundongos , Pandemias , Análise de Sequência de RNA , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/metabolismo , Éxons VDJ
7.
N Engl J Med ; 382(19): 1811-1822, 2020 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-32374962

RESUMO

BACKGROUND: Primary hemophagocytic lymphohistiocytosis is a rare syndrome characterized by immune dysregulation and hyperinflammation. It typically manifests in infancy and is associated with high mortality. METHODS: We investigated the efficacy and safety of emapalumab (a human anti-interferon-γ antibody), administered with dexamethasone, in an open-label, single-group, phase 2-3 study involving patients who had received conventional therapy before enrollment (previously treated patients) and previously untreated patients who were 18 years of age or younger and had primary hemophagocytic lymphohistiocytosis. The patients could enter a long-term follow-up study until 1 year after allogeneic hematopoietic stem-cell transplantation or until 1 year after the last dose of emapalumab, if transplantation was not performed. The planned 8-week treatment period could be shortened or extended if needed according to the timing of transplantation. The primary efficacy end point was the overall response, which was assessed in the previously treated patients according to objective clinical and laboratory criteria. RESULTS: At the cutoff date of July 20, 2017, a total of 34 patients (27 previously treated patients and 7 previously untreated patients) had received emapalumab; 26 patients completed the study. A total of 63% of the previously treated patients and 65% of the patients who received an emapalumab infusion had a response; these percentages were significantly higher than the prespecified null hypothesis of 40% (P = 0.02 and P = 0.005, respectively). In the previously treated group, 70% of the patients were able to proceed to transplantation, as were 65% of the patients who received emapalumab. At the last observation, 74% of the previously treated patients and 71% of the patients who received emapalumab were alive. Emapalumab was not associated with any organ toxicity. Severe infections developed in 10 patients during emapalumab treatment. Emapalumab was discontinued in 1 patient because of disseminated histoplasmosis. CONCLUSIONS: Emapalumab was an efficacious targeted therapy for patients with primary hemophagocytic lymphohistiocytosis. (Funded by NovImmune and the European Commission; NI-0501-04 and NI-0501-05 ClinicalTrials.gov numbers, NCT01818492 and NCT02069899.).


Assuntos
Anticorpos Monoclonais/administração & dosagem , Anticorpos Neutralizantes/administração & dosagem , Interferon gama/antagonistas & inibidores , Linfo-Histiocitose Hemofagocítica/tratamento farmacológico , Adolescente , Idade de Início , Anti-Inflamatórios/administração & dosagem , Anticorpos Monoclonais/efeitos adversos , Anticorpos Neutralizantes/efeitos adversos , Quimiocina CXCL9/sangue , Criança , Pré-Escolar , Dexametasona/administração & dosagem , Quimioterapia Combinada , Feminino , Transplante de Células-Tronco Hematopoéticas , Humanos , Lactente , Infecções/etiologia , Estimativa de Kaplan-Meier , Linfo-Histiocitose Hemofagocítica/complicações , Linfo-Histiocitose Hemofagocítica/mortalidade , Linfo-Histiocitose Hemofagocítica/terapia , Masculino , Resultado do Tratamento
8.
Emerg Microbes Infect ; 9(1): 664-675, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32193996

RESUMO

The H7N9 viruses have been circulating for six years. The insertion of a polybasic cleavage site in the haemagglutinin (HA) protein of H7N9 has resulted in the emergence of a highly pathogenic (HP) avian influenza virus. Currently, there are limited studies on neutralizing monoclonal antibodies(mAbs) against HP H7N9 AIVs. In this study, mice were immunized with inactivated H7N9 vaccine of A/ZJU01/PR8/2013 to produce murine mAbs. Finally, two murine mAbs against the HA of low pathogenic (LP) virus were produced and characterized. Characterization included determining mAbs binding breadth and affinity, in vitro neutralization capacity, and potential in vivo protection. Two of these mAbs, 1H10 and 2D1, have been identified to have therapeutic and prophylactic efficacy against the HP strain in mouse passive transfer-viral challenge experiments. The mAb 1H10 was most efficacious, even if the treatment-time was as late as 72 h post-infection, or the therapeutic dose was as low as 1 mg/kg; and it was confirmed to have haemagglutination inhibition and neutralizing activity on both LP-and HP-H7N9 strains. Further study indicated that the protection provided by 2D1 was mediated by antibody-dependent cellular cytotoxicity. The mAbs described here provide promising results and merit further development into potential antiviral therapeutics for H7N9 infection.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Subtipo H7N9 do Vírus da Influenza A/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Infecções por Orthomyxoviridae/terapia , Animais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Neutralizantes/administração & dosagem , Anticorpos Antivirais/administração & dosagem , Citotoxicidade Celular Dependente de Anticorpos , Anticorpos Amplamente Neutralizantes/imunologia , Linhagem Celular , Mapeamento de Epitopos , Feminino , Testes de Hemaglutinação , Glicoproteínas de Hemaglutininação de Vírus da Influenza , Imunização Passiva , Subtipo H7N9 do Vírus da Influenza A/metabolismo , Subtipo H7N9 do Vírus da Influenza A/patogenicidade , Camundongos , Camundongos Endogâmicos BALB C , Mutação , Testes de Neutralização , Filogenia
9.
PLoS Negl Trop Dis ; 14(3): e0008143, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32160203

RESUMO

Rift Valley fever virus (RVFV) is a zoonotic arbovirus that causes severe disease in humans and ruminants. The infection is characterized by abortions in pregnant animals, high mortality in neonates as well as febrile illness in humans that develop in 1% of cases encephalitis or hemorrhagic fever. There is presently no specific antiviral treatment for RVFV infection available. In this study, two monoclonal antibodies (mAbs), raised against glycoprotein Gn, were applied in a therapeutic study. Treatment of RVFV infected mice with neutralizing mAb Gn3 alone at two different time points (30 minutes before or 30 minutes after virus challenge) showed only moderate efficacy of about 58.3% survival in both applications. However, a combination therapy together with non-neutralizing mAb Gn32 demonstrated complete protection (100% survival) when applied 30 minutes after the lethal challenge dose. The increase of mAb efficacy is probably based on cooperative neutralization effects. These data suggest that a combination therapy with mAbs Gn3 and Gn32 could be an effective treatment option against RVFV infection.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Anticorpos Neutralizantes/administração & dosagem , Anticorpos Antivirais/administração & dosagem , Fatores Imunológicos/administração & dosagem , Febre do Vale de Rift/prevenção & controle , Animais , Antígenos Virais/imunologia , Modelos Animais de Doenças , Feminino , Glicoproteínas/imunologia , Masculino , Camundongos Endogâmicos BALB C , Febre do Vale de Rift/imunologia , Vírus da Febre do Vale do Rift/imunologia , Análise de Sobrevida , Resultado do Tratamento
10.
Proc Natl Acad Sci U S A ; 117(14): 7981-7989, 2020 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-32209664

RESUMO

Human infection by Zika virus (ZIKV) during pregnancy can lead to vertical transmission and fetal aberrations, including microcephaly. Prophylactic administration of antibodies can diminish or prevent ZIKV infection in animal models, but whether passive immunization can protect nonhuman primates and their fetuses during pregnancy has not been determined. Z004 and Z021 are neutralizing monoclonal antibodies to domain III of the envelope (EDIII) of ZIKV. Together the two antibodies protect nonpregnant macaques against infection even after Fc modifications to prevent antibody-dependent enhancement (ADE) in vitro and extend their half-lives. Here we report on prophylactic coadministration of the Fc-modified antibodies to pregnant rhesus macaques challenged three times with ZIKV during first and second trimester. The two antibodies did not entirely eliminate maternal viremia but limited vertical transmission, protecting the fetus from neurologic damage. Thus, maternal passive immunization with two antibodies to EDIII can shield primate fetuses from the harmful effects of ZIKV.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Transmissão Vertical de Doença Infecciosa/prevenção & controle , Complicações Infecciosas na Gravidez/prevenção & controle , Infecção por Zika virus/prevenção & controle , Zika virus/imunologia , Animais , Animais Recém-Nascidos , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/administração & dosagem , Anticorpos Neutralizantes/genética , Anticorpos Neutralizantes/imunologia , Modelos Animais de Doenças , Quimioterapia Combinada , Feminino , Feto/imunologia , Feto/virologia , Células HEK293 , Humanos , Fragmentos Fc das Imunoglobulinas/administração & dosagem , Fragmentos Fc das Imunoglobulinas/genética , Fragmentos Fc das Imunoglobulinas/imunologia , Imunoglobulina G/administração & dosagem , Imunoglobulina G/genética , Imunoglobulina G/imunologia , Gravidez , Complicações Infecciosas na Gravidez/imunologia , Complicações Infecciosas na Gravidez/virologia , Engenharia de Proteínas , RNA Viral/isolamento & purificação , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Zika virus/genética , Zika virus/patogenicidade , Infecção por Zika virus/imunologia , Infecção por Zika virus/transmissão , Infecção por Zika virus/virologia
11.
Anesthesiology ; 132(4): 795-807, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32101978

RESUMO

BACKGROUND: Community-acquired pneumonia and associated sepsis cause high mortality despite antibiotic treatment. Uncontrolled inflammatory host responses contribute to the unfavorable outcome by driving lung and extrapulmonary organ failure. The complement fragment C5a holds significant proinflammatory functions and is associated with tissue damage in various inflammatory conditions. The authors hypothesized that C5a concentrations are increased in pneumonia and C5a neutralization promotes barrier stabilization in the lung and is protective in pneumococcal pulmonary sepsis. METHODS: The authors investigated regulation of C5a in pneumonia in a prospective patient cohort and in experimental pneumonia. Two complementary models of murine pneumococcal pneumonia were applied. Female mice were treated with NOX-D19, a C5a-neutralizing L-RNA-aptamer. Lung, liver, and kidney injury and the inflammatory response were assessed by measuring pulmonary permeability (primary outcome), pulmonary and blood leukocytes, cytokine concentrations in lung and blood, and bacterial load in lung, spleen, and blood, and performing histologic analyses of tissue damage, apoptosis, and fibrin deposition (n = 5 to 13). RESULTS: In hospitalized patients with pneumonia (n = 395), higher serum C5a concentrations were observed compared to healthy subjects (n = 24; 6.3 nmol/l [3.9 to 10.0] vs. 4.5 nmol/l [3.8 to 6.6], median [25 to 75% interquartile range]; difference: 1.4 [95% CI, 0.1 to 2.9]; P = 0.029). Neutralization of C5a in mice resulted in lower pulmonary permeability in pneumococcal pneumonia (1.38 ± 0.89 vs. 3.29 ± 2.34, mean ± SD; difference: 1.90 [95% CI, 0.15 to 3.66]; P = 0.035; n = 10 or 11) or combined severe pneumonia and mechanical ventilation (2.56 ± 1.17 vs. 7.31 ± 5.22; difference: 4.76 [95% CI, 1.22 to 8.30]; P = 0.011; n = 9 or 10). Further, C5a neutralization led to lower blood granulocyte colony-stimulating factor concentrations and protected against sepsis-associated liver injury. CONCLUSIONS: Systemic C5a is elevated in pneumonia patients. Neutralizing C5a protected against lung and liver injury in pneumococcal pneumonia in mice. Early neutralization of C5a might be a promising adjunctive treatment strategy to improve outcome in community-acquired pneumonia.


Assuntos
Aptâmeros de Nucleotídeos/administração & dosagem , Complemento C5a/antagonistas & inibidores , Pneumonia Pneumocócica/sangue , Pneumonia Pneumocócica/prevenção & controle , Sepse/sangue , Sepse/prevenção & controle , Animais , Anticorpos Neutralizantes/administração & dosagem , Biomarcadores/sangue , Estudos de Coortes , Complemento C5a/metabolismo , Feminino , Fatores Imunológicos/antagonistas & inibidores , Fatores Imunológicos/sangue , Camundongos , Camundongos Endogâmicos C57BL , Estudos Prospectivos
12.
Nat Commun ; 11(1): 70, 2020 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-31911610

RESUMO

Vertical transmission accounts for most human immunodeficiency virus (HIV) infection in children, and treatments for newborns are needed to abrogate infection or limit disease progression. We showed previously that short-term broadly neutralizing antibody (bNAb) therapy given 24 h after oral exposure cleared simian-human immunodeficiency virus (SHIV) in a macaque model of perinatal infection. Here, we report that all infants given either a single dose of bNAbs at 30 h, or a 21-day triple-drug ART regimen at 48 h, are aviremic with almost no virus in tissues. In contrast, bNAb treatment beginning at 48 h leads to tight control without adaptive immune responses in half of animals. We conclude that both bNAbs and ART mediate effective post-exposure prophylaxis in infant macaques within 30-48 h of oral SHIV exposure. Our findings suggest that optimizing the treatment regimen may extend the window of opportunity for preventing perinatal HIV infection when treatment is delayed.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Anticorpos Neutralizantes/administração & dosagem , Anticorpos Anti-HIV/administração & dosagem , Transmissão Vertical de Doença Infecciosa/prevenção & controle , Síndrome de Imunodeficiência Adquirida dos Símios/prevenção & controle , Imunidade Adaptativa , Animais , Modelos Animais de Doenças , Feminino , Infecções por HIV/imunologia , Infecções por HIV/prevenção & controle , Infecções por HIV/transmissão , HIV-1/imunologia , HIV-1/fisiologia , Humanos , Macaca , Macaca mulatta , Masculino , Profilaxia Pós-Exposição , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/transmissão , Vírus da Imunodeficiência Símia/imunologia , Vírus da Imunodeficiência Símia/fisiologia
13.
Medicina (B Aires) ; 79(Spec 6/1): 534-539, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31864222

RESUMO

Since its first isolation in 1983, over 77 million people became infected with the human immunodeficiency virus (HIV), and only one case has been reported in which the virus was completely removed from the body. A recent second case was reported that remains to be confirmed. Antiretroviral therapy (ART) manages to control blood viral replication and, consequently, to restore -at least partially- the functions of the immune system, with a notable positive impact on the morbidity and mortality associated with the virus. However, given the difficulty in eliminating the virus from the body, treatment should be given for life. This long-term exposure to antiretroviral drugs implies the risk of generating intolerance, toxic effects, gaps in adherence and the potential selection of resistance mutations. Another limitation is the high cost of treating 37 million persons living with HIV, most of whom are living in resource-limited countries and relying on international aid initiatives. Having these challenges in mind, there is general agreement that new approaches for preventing and treating HIV infection are needed to control the epidemic, while vaccine development efforts continue. In this regard, new generation broadly neutralising monoclonal antibodies (bnMAbs) against the HIV viral envelope protein can prevent virus acquisition, reduce viremia, enhance immunity, and induce the killing of infected cells in animal models of HIV infection. Most importantly, some clinical trials have shown that bnMAbs could effectively d ecrease viremia and delay viral rebound in people chronically infected with HIV.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Anticorpos Monoclonais/administração & dosagem , Anticorpos Neutralizantes/administração & dosagem , Infecções por HIV/prevenção & controle , Infecções por HIV/terapia , Animais , Quimioterapia Combinada , HIV-1/imunologia , Humanos , Carga Viral
14.
Emerg Infect Dis ; 25(11): 2064-2073, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31625835

RESUMO

West Nile Virus (WNV) can result in clinically severe neurologic disease. There is no treatment for WNV infection, but administration of anti-WNV polyclonal human antibody has demonstrated efficacy in animal models. We compared Omr-IgG-am, an immunoglobulin product with high titers of anti-WNV antibody, with intravenous immunoglobulin (IVIG) and normal saline to assess safety and efficacy in patients with WNV neuroinvasive disease as part of a phase I/II, randomized, double-blind, multicenter study in North America. During 2003-2006, a total of 62 hospitalized patients were randomized to receive Omr-IgG-am, standard IVIG, or normal saline (3:1:1). The primary endpoint was medication safety. Secondary endpoints were morbidity and mortality, measured using 4 standardized assessments of cognitive and functional status. The death rate in the study population was 12.9%. No significant differences were found between groups receiving Omr-IgG-am compared with IVIG or saline for either the safety or efficacy endpoints.


Assuntos
Viroses do Sistema Nervoso Central/tratamento farmacológico , Viroses do Sistema Nervoso Central/virologia , Imunoglobulina G/uso terapêutico , Imunoglobulinas Intravenosas/uso terapêutico , Febre do Nilo Ocidental/tratamento farmacológico , Febre do Nilo Ocidental/virologia , Vírus do Nilo Ocidental , Adulto , Idoso , Anticorpos Neutralizantes/administração & dosagem , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/administração & dosagem , Anticorpos Antivirais/imunologia , Viroses do Sistema Nervoso Central/imunologia , Feminino , Humanos , Imunoglobulina G/administração & dosagem , Imunoglobulinas Intravenosas/administração & dosagem , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Febre do Nilo Ocidental/imunologia , Vírus do Nilo Ocidental/imunologia
15.
Int J Mol Sci ; 20(20)2019 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-31614869

RESUMO

Middle East respiratory syndrome coronavirus (MERS-CoV) induces severe aggravating respiratory failure in infected patients, frequently resulting in mechanical ventilation. As limited therapeutic antibody is accumulated in lung tissue following systemic administration, inhalation is newly recognized as an alternative, possibly better, route of therapeutic antibody for pulmonary diseases. The nebulization process, however, generates diverse physiological stresses, and thus, the therapeutic antibody must be resistant to these stresses, remain stable, and form minimal aggregates. We first isolated a MERS-CoV neutralizing antibody that is reactive to the receptor-binding domain (RBD) of spike (S) glycoprotein. To increase stability, we introduced mutations into the complementarity-determining regions (CDRs) of the antibody. In the HCDRs (excluding HCDR3) in this clone, two hydrophobic residues were replaced with Glu, two residues were replaced with Asp, and four residues were replaced with positively charged amino acids. In LCDRs, only two Leu residues were replaced with Val. These modifications successfully generated a clone with significantly greater stability and equivalent reactivity and neutralizing activity following nebulization compared to the original clone. In summary, we generated a MERS-CoV neutralizing human antibody that is reactive to recombinant MERS-CoV S RBD protein for delivery via a pulmonary route by introducing stabilizing mutations into five CDRs.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Regiões Determinantes de Complementaridade/imunologia , Coronavírus da Síndrome Respiratória do Oriente Médio/imunologia , Administração por Inalação , Animais , Anticorpos Neutralizantes/administração & dosagem , Anticorpos Neutralizantes/genética , Anticorpos Antivirais/administração & dosagem , Anticorpos Antivirais/genética , Chlorocebus aethiops , Regiões Determinantes de Complementaridade/genética , Humanos , Células Vero
16.
Nat Med ; 25(9): 1402-1407, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31501610

RESUMO

Natalizumab (NZM), a humanized monoclonal IgG4 antibody to α4 integrins, is used to treat patients with relapsing-remitting multiple sclerosis (MS)1,2, but in about 6% of the cases persistent neutralizing anti-drug antibodies (ADAs) are induced leading to therapy discontinuation3,4. To understand the basis of the ADA response and the mechanism of ADA-mediated neutralization, we performed an in-depth analysis of the B and T cell responses in two patients. By characterizing a large panel of NZM-specific monoclonal antibodies, we found that, in both patients, the response was polyclonal and targeted different epitopes of the NZM idiotype. The neutralizing activity was acquired through somatic mutations and correlated with a slow dissociation rate, a finding that was supported by structural data. Interestingly, in both patients, the analysis of the CD4+ T cell response, combined with mass spectrometry-based peptidomics, revealed a single immunodominant T cell epitope spanning the FR2-CDR2 region of the NZM light chain. Moreover, a CDR2-modified version of NZM was not recognized by T cells, while retaining binding to α4 integrins. Collectively, our integrated analysis identifies the basis of T-B collaboration that leads to ADA-mediated therapeutic resistance and delineates an approach to design novel deimmunized antibodies for autoimmune disease and cancer treatment.


Assuntos
Anticorpos Neutralizantes/administração & dosagem , Epitopos de Linfócito T/imunologia , Esclerose Múltipla/tratamento farmacológico , Natalizumab/administração & dosagem , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Neutralizantes/química , Formação de Anticorpos/efeitos dos fármacos , Formação de Anticorpos/imunologia , Linfócitos B/efeitos dos fármacos , Humanos , Imunoglobulina G/química , Imunoglobulina G/imunologia , Integrina alfa4/antagonistas & inibidores , Integrina alfa4/imunologia , Esclerose Múltipla/imunologia , Esclerose Múltipla/patologia , Conformação Proteica/efeitos dos fármacos , Linfócitos T/química , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia
17.
Cell Host Microbe ; 26(3): 336-346.e3, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31513771

RESUMO

Passively administered broadly neutralizing antibodies (bNAbs) targeting the HIV-1 envelope glycoprotein (Env) have been shown to protect non-human primates (NHPs) against chimeric simian-human immunodeficiency virus (SHIV) infection. With data from multiple non-human primate SHIV challenge studies that used single bNAbs, we conducted a meta-analysis to examine the relationship between predicted serum 50% neutralization titer (ID50) against the challenge virus and infection outcome. In a logistic model that adjusts for bNAb epitopes and challenge viruses, serum ID50 had a highly significant effect on infection risk (p < 0.001). The estimated ID50 to achieve 50%, 75%, and 95% protection was 91 (95% confidence interval [CI]: 55, 153), 219 (117, 410), and 685 (319, 1471), respectively. This analysis indicates that serum neutralizing titer against the relevant virus is a key parameter of protection and that protection from acquisition by a single bNAb might require substantial levels of neutralization at the time of exposure.


Assuntos
Anticorpos Neutralizantes/administração & dosagem , Anticorpos Neutralizantes/imunologia , Imunização Passiva , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/prevenção & controle , Vírus da Imunodeficiência Símia/imunologia , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Epitopos/imunologia , Feminino , Infecções por HIV/imunologia , Concentração Inibidora 50 , Modelos Logísticos , Macaca mulatta , Masculino , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia
18.
APMIS ; 127(10): 671-680, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31344276

RESUMO

Regardless of the communal impact of Shiga toxins, till today neither a specific treatment nor licensed vaccine is available. Lactococcus lactis (L. lactis), generally regarded as safe organism, is well known to provide a valuable approach regarding the oral delivery of vaccines. This study was undertaken to evaluate the protective efficacy of Stx2a1 expressed in nisin-inducible L. lactis, against Shiga toxins (Stx1, Stx2) in mouse model. Oral immunization of BALB/c mice with LL-Stx2a1 elicited significant serum antibody titer with elevated fecal and serum IgA, along with minimized intestinal and kidney damage resulting in survival of immunized animals at 84% and 100% when challenged with 10 × LD50 of Escherichia coli O157 and Shigella dysenteriae toxins, respectively. HeLa cells incubated with immune sera and toxin mixture revealed high neutralizing capacity with 90% cell survivability against both the toxins. Mice immunized passively with both toxins and antibody mixture survived the observation period of 15 days, and the controls administered with sham sera and toxins were succumbed to death within 3 days. Our results revealed protective efficacy and toxin neutralization ability of LL-Stx2a1, proposing it as an oral vaccine candidate against Shiga toxicity mediated by E. coli O157 and S. dysenteriae.


Assuntos
Vacinas Bacterianas/administração & dosagem , Vacinas Bacterianas/imunologia , Escherichia coli O157/imunologia , Envenenamento/prevenção & controle , Toxina Shiga/imunologia , Toxina Shiga/toxicidade , Shigella dysenteriae/imunologia , Administração Oral , Animais , Anticorpos Antibacterianos/administração & dosagem , Anticorpos Antibacterianos/sangue , Anticorpos Neutralizantes/administração & dosagem , Anticorpos Neutralizantes/sangue , Antitoxinas/administração & dosagem , Antitoxinas/sangue , Vacinas Bacterianas/genética , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Portadores de Fármacos/administração & dosagem , Escherichia coli O157/genética , Vetores Genéticos/administração & dosagem , Células HeLa , Humanos , Lactococcus lactis/genética , Camundongos , Camundongos Endogâmicos BALB C , Toxina Shiga/genética , Shigella dysenteriae/genética , Análise de Sobrevida , Resultado do Tratamento , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia
19.
Nat Commun ; 10(1): 2699, 2019 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-31221976

RESUMO

Human cytomegalovirus (CMV) causes a wide array of disease to diverse populations of immune-compromised individuals. Thus, a more comprehensive understanding of how CMV enters numerous host cell types is necessary to further delineate the complex nature of CMV pathogenesis and to develop targeted therapeutics. To that end, we establish a vaccination strategy utilizing membrane vesicles derived from epithelial cells to generate a library of monoclonal antibodies (mAbs) targeting cell surface proteins in their native conformation. A high-throughput inhibition assay is employed to screen these antibodies for their ability to limit infection, and mAbs targeting CD46 are identified. In addition, a significant reduction of viral proliferation in CD46-KO epithelial cells confirms a role for CD46 function in viral dissemination. Further, we demonstrate a CD46-dependent entry pathway of virus infection in trophoblasts, but not in fibroblasts, highlighting the complexity of CMV entry and identifying CD46 as an entry factor in congenital infection.


Assuntos
Infecções por Citomegalovirus/imunologia , Citomegalovirus/imunologia , Interações Hospedeiro-Patógeno/imunologia , Proteína Cofatora de Membrana/imunologia , Internalização do Vírus , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/administração & dosagem , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/administração & dosagem , Anticorpos Antivirais/imunologia , Linhagem Celular , Infecções por Citomegalovirus/prevenção & controle , Infecções por Citomegalovirus/virologia , Células Epiteliais/imunologia , Células Epiteliais/virologia , Fibroblastos/imunologia , Fibroblastos/virologia , Técnicas de Inativação de Genes , Humanos , Proteína Cofatora de Membrana/genética , RNA Interferente Pequeno/metabolismo , Trofoblastos/imunologia , Trofoblastos/virologia , Vacinas Virais/administração & dosagem , Vacinas Virais/imunologia
20.
Circulation ; 140(9): 751-764, 2019 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-31220942

RESUMO

BACKGROUND: Myocardial ischemia-reperfusion (MI/R) injury is a significant clinical problem without effective therapy. Unbiased omics approaches may reveal key MI/R mediators to initiate MI/R injury. METHODS: We used a dynamic transcriptome analysis of mouse heart exposed to various MI/R periods to identify S100a8/a9 as an early mediator. Using loss/gain-of-function approaches to understand the role of S100a8/a9 in MI/R injury, we explored the mechanisms through transcriptome and functional experiment. Dynamic serum S100a8/a9 levels were measured in patients with acute myocardial infarction before and after percutaneous coronary intervention. Patients were prospectively followed for the occurrence of major adverse cardiovascular events. RESULTS: S100a8/a9 was identified as the most significantly upregulated gene during the early reperfusion stage. Knockout of S100a9 markedly decreased cardiomyocyte death and improved heart function, whereas hematopoietic overexpression of S100a9 exacerbated MI/R injury. Transcriptome/functional studies revealed that S100a8/a9 caused mitochondrial respiratory dysfunction in cardiomyocytes. Mechanistically, S100a8/a9 downregulated NDUF gene expression with subsequent mitochondrial complex I inhibition via Toll-like receptor 4/Erk-mediated Pparg coactivator 1 alpha/nuclear respiratory factor 1 signaling suppression. Administration of S100a9 neutralizing antibody significantly reduced MI/R injury and improved cardiac function. Finally, we demonstrated that serum S100a8/a9 levels were significantly increased 1 day after percutaneous coronary intervention in patients with acute myocardial infarction, and elevated S100a8/a9 levels were associated with the incidence of major adverse cardiovascular events. CONCLUSIONS: Our study identified S100a8/a9 as a master regulator causing cardiomyocyte death in the early stage of MI/R injury via the suppression of mitochondrial function. Targeting S100a8/a9-intiated signaling may represent a novel therapeutic intervention against MI/R injury. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT03752515.


Assuntos
Apoptose , Calgranulina B/metabolismo , Mitocôndrias/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Animais , Anticorpos Neutralizantes/administração & dosagem , Calgranulina A/sangue , Calgranulina B/genética , Calgranulina B/imunologia , Modelos Animais de Doenças , Complexo I de Transporte de Elétrons/antagonistas & inibidores , Complexo I de Transporte de Elétrons/metabolismo , Insuficiência Cardíaca/etiologia , Humanos , Potencial da Membrana Mitocondrial , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/cirurgia , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Intervenção Coronária Percutânea , Transdução de Sinais
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