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1.
Cell Rep ; 34(11): 108852, 2021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-33730580

RESUMO

As the global COVID-19 pandemic progresses, it is paramount to gain knowledge on adaptive immunity to SARS-CoV-2 in children to define immune correlates of protection upon immunization or infection. We analyzed anti-SARS-CoV-2 antibodies and their neutralizing activity (PRNT) in 66 COVID-19-infected children at 7 (±2) days after symptom onset. Individuals with specific humoral responses presented faster virus clearance and lower viral load associated with a reduced in vitro infectivity. We demonstrated that the frequencies of SARS-CoV-2-specific CD4+CD40L+ T cells and Spike-specific B cells were associated with the anti-SARS-CoV-2 antibodies and the magnitude of neutralizing activity. The plasma proteome confirmed the association between cellular and humoral SARS-CoV-2 immunity, and PRNT+ patients show higher viral signal transduction molecules (SLAMF1, CD244, CLEC4G). This work sheds lights on cellular and humoral anti-SARS-CoV-2 responses in children, which may drive future vaccination trial endpoints and quarantine measures policies.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , /imunologia , Imunidade Adaptativa/imunologia , Linfócitos B/imunologia , Linfócitos T CD4-Positivos/imunologia , Criança , Humanos , Imunidade Humoral/imunologia , Proteoma/imunologia , Transdução de Sinais/imunologia , Carga Viral/imunologia
2.
Physiol Rep ; 9(4): e14761, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33625796

RESUMO

COVID-19 causes severe disease with poor outcomes. We tested the hypothesis that early SARS-CoV-2 viral infection disrupts innate immune responses. These changes may be important for understanding subsequent clinical outcomes. We obtained residual nasopharyngeal swab samples from individuals who requested COVID-19 testing for symptoms at drive-through COVID-19 clinical testing sites operated by the University of Utah. We applied multiplex immunoassays, real-time polymerase chain reaction assays and quantitative proteomics to 20 virus-positive and 20 virus-negative samples. ACE-2 transcripts increased with infection (OR =17.4, 95% CI [CI] =4.78-63.8) and increasing viral N1 protein transcript load (OR =1.16, CI =1.10-1.23). Transcripts for two interferons (IFN) were elevated, IFN-λ1 (OR =71, CI =7.07-713) and IFN-λ2 (OR =40.2, CI =3.86-419), and closely associated with viral N1 transcripts (OR =1.35, CI =1.23-1.49 and OR =1.33 CI =1.20-1.47, respectively). Only transcripts for IP-10 were increased among systemic inflammatory cytokines that we examined (OR =131, CI =1.01-2620). We found widespread discrepancies between transcription and translation. IFN proteins were unchanged or decreased in infected samples (IFN-γ OR =0.90 CI =0.33-0.79, IFN-λ2,3 OR =0.60 CI =0.48-0.74) suggesting viral-induced shut-off of host antiviral protein responses. However, proteins for IP-10 (OR =3.74 CI =2.07-6.77) and several interferon-stimulated genes (ISG) increased with viral load (BST-1 OR =25.1, CI =3.33-188; IFIT1 OR =19.5, CI =4.25-89.2; IFIT3 OR =245, CI =15-4020; MX-1 OR =3.33, CI =1.44-7.70). Older age was associated with substantial modifications of some effects. Ambulatory symptomatic patients had an innate immune response with SARS-CoV-2 infection characterized by elevated IFN, proinflammatory cytokine and ISG transcripts, but there is evidence of a viral-induced host shut-off of antiviral responses. Our findings may characterize the disrupted immune landscape common in patients with early disease.


Assuntos
/imunologia , Imunidade Inata/imunologia , Doenças Nasofaríngeas/virologia , Carga Viral/imunologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Criança , Citocinas/sangue , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Nasofaríngeas/imunologia , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Fatores Sexuais , Adulto Jovem
3.
Nature ; 591(7848): 124-130, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33494096

RESUMO

Although infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has pleiotropic and systemic effects in some individuals1-3, many others experience milder symptoms. Here, to gain a more comprehensive understanding of the distinction between severe and mild phenotypes in the pathology of coronavirus disease 2019 (COVID-19) and its origins, we performed a whole-blood-preserving single-cell analysis protocol to integrate contributions from all major immune cell types of the blood-including neutrophils, monocytes, platelets, lymphocytes and the contents of the serum. Patients with mild COVID-19 exhibit a coordinated pattern of expression of interferon-stimulated genes (ISGs)3 across every cell population, whereas these ISG-expressing cells are systemically absent in patients with severe disease. Paradoxically, individuals with severe COVID-19 produce very high titres of anti-SARS-CoV-2 antibodies and have a lower viral load compared to individuals with mild disease. Examination of the serum from patients with severe COVID-19 shows that these patients uniquely produce antibodies that functionally block the production of the ISG-expressing cells associated with mild disease, by activating conserved signalling circuits that dampen cellular responses to interferons. Overzealous antibody responses pit the immune system against itself in many patients with COVID-19, and perhaps also in individuals with other viral infections. Our findings reveal potential targets for immunotherapies in patients with severe COVID-19 to re-engage viral defence.


Assuntos
Anticorpos Antivirais/imunologia , /fisiopatologia , Interferons/antagonistas & inibidores , Interferons/imunologia , /patogenicidade , Anticorpos Antivirais/sangue , Formação de Anticorpos , Sequência de Bases , /virologia , Feminino , Humanos , Imunoglobulina G/imunologia , Interferons/metabolismo , Masculino , Neutrófilos/imunologia , Neutrófilos/patologia , Domínios Proteicos , Receptor de Interferon alfa e beta/antagonistas & inibidores , Receptor de Interferon alfa e beta/imunologia , Receptor de Interferon alfa e beta/metabolismo , Receptores de IgG/imunologia , Análise de Célula Única , Carga Viral/imunologia
5.
Viruses ; 13(2)2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33498165

RESUMO

Anal squamous cell carcinoma is the most frequent virus-related non-AIDS-defining neoplasia among HIV-infected individuals, especially MSM. The objectives of this study were to analyze the effectiveness of the quadrivalent HPV (qHPV) vaccine to prevent anal ≥ high-grade squamous intraepithelial lesions (≥HSILs), external ano-genital lesions (EAGLs), and infection by qHPV vaccine genotypes in HIV+ MSM, and to study the immunogenicity of the vaccine and risk factors for ≥ HSILs. This study is nested within a randomized, double-blind, placebo-controlled trial of the qHPV vaccine, which enrolled participants between May 2012 and May 2014, with a 48-month follow-up. A vaccine or placebo was administered at 0, 2, and 6 months, and vaccine antibody titers were evaluated at 7, 12, 24, 36, and 48 months. Data were gathered at 12, 24, 36, and 48 months on sexual habits, CD4/CD8 cell/counts, HIV viral load, and the results of cytology (Thin Prep® Pap Test), HPV PCR genotyping (Linear Array HPV Genotyping Test), and high-resolution anoscopy (Zeiss 150 fc© colposcope). The study included 129 patients (mean age of 38.8 years, 40 [31%] with a history of AIDS, 119 [92.2%] receiving ART, and 4 [3.3%] with virological failure), 66 (51.2%) in vaccine arm and 63 (48.4%) in placebo arm. The vaccine and placebo groups did not differ in ≥ HSILs (14.1 vs. 13.1%, respectively, p = 0.98) or EAGL (11.1 vs. 6.8%, p = 0.4) rates during follow-up; however, a protective effect against HPV 6 was observed during the first year of follow-up in the vaccine versus placebo group (7.5% vs. 23.4%; p = 0.047). A between-arm difference (p = 0.0001) in antibodies against qHPV vaccine genotypes was observed at 7 months (76.9% in vaccine arm vs. 30.2% in placebo arm), 12 months (68.1% vs. 26.5%), 24 months (75% vs. 32.5%), 36 months (90% vs. 24.4%), and 48 months (87.2% vs. 30%). Finally, the factor associated with the risk of anal ≥ HSIL onset during the four-year follow-up was the receipt of the last dose of the vaccine less than 6 months earlier in comparison to those vaccinated for a longer period (82.4% vs. 17.6% (OR 0.869 [95% CI, 0.825-0.917]). Vaccine and placebo arms did not significantly differ in ≥ HSIL or EAGL rates or in protection against infection by HPV genotype vaccine except for HPV6 at 12 months after the first dose. A long-lasting immune response was observed in almost all the vaccinated men. The main protective factor against ≥ HSIL was to have completed the vaccination regimen more than 6 months earlier.


Assuntos
Anticorpos Antivirais/sangue , Neoplasias do Ânus/prevenção & controle , Vacina Quadrivalente Recombinante contra HPV tipos 6, 11, 16, 18/administração & dosagem , Vacina Quadrivalente Recombinante contra HPV tipos 6, 11, 16, 18/imunologia , Infecções por Papillomavirus/prevenção & controle , Adulto , Canal Anal/virologia , Neoplasias do Ânus/virologia , Contagem de Linfócito CD4 , Coinfecção/virologia , Infecções por HIV/virologia , Homossexualidade Masculina , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Infecções por Papillomavirus/imunologia , Infecções por Papillomavirus/virologia , Análise de Regressão , Minorias Sexuais e de Gênero , Espanha , Carga Viral/imunologia
6.
J Clin Virol ; 135: 104713, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33352470

RESUMO

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can spread from symptomatic patients with COVID-19, but also from asymptomatic individuals. Therefore, robust surveillance and timely interventions are essential for the control of virus spread within the community. In this regard the frequency of testing and speed of reporting, but not the test sensitivity alone, play a crucial role. OBJECTIVES: In order to reduce the costs and meet the expanding demands in real-time RT-PCR (rRT-PCR) testing for SARS-CoV-2, complementary assays, such as rapid antigen tests, have been developed. Rigorous analysis under varying conditions is required to assess the clinical performance of these tests and to ensure reproducible results. RESULTS: We evaluated the sensitivity and specificity of a recently licensed rapid antigen test using 137 clinical samples in two institutions. Test sensitivity was between 88.2-89.6 % when applied to samples with viral loads typically seen in infectious patients. Of 32 rRT-PCR positive samples, 19 demonstrated infectivity in cell culture, and 84 % of these samples were reactive with the antigen test. Seven full-genome sequenced SARS-CoV-2 isolates and SARS-CoV-1 were detected with this antigen test, with no cross-reactivity against other common respiratory viruses. CONCLUSIONS: Numerous antigen tests are available for SARS-CoV-2 testing and their performance to detect infectious individuals may vary. Head-to-head comparison along with cell culture testing for infectivity may prove useful to identify better performing antigen tests. The antigen test analyzed in this study is easy-to-use, inexpensive, and scalable. It can be helpful in monitoring infection trends and thus has potential to reduce transmission.


Assuntos
Antígenos Virais/genética , /diagnóstico , /genética , /virologia , Células CACO-2 , Linhagem Celular Tumoral , Células Cultivadas , Genoma Viral/genética , Humanos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Carga Viral/imunologia
7.
PLoS Pathog ; 16(12): e1009177, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33370400

RESUMO

HIV-1 strains harboring immune escape mutations can persist in circulation, but the impact of selection by multiple HLA alleles on population HIV-1 dynamics remains unclear. In Japan, HIV-1 Reverse Transcriptase codon 135 (RT135) is under strong immune pressure by HLA-B*51:01-restricted and HLA-B*52:01-restricted T cells that target a key epitope in this region (TI8; spanning RT codons 128-135). Major population-level shifts have occurred at HIV-1 RT135 during the Japanese epidemic, which first affected hemophiliacs (via imported contaminated blood products) and subsequently non-hemophiliacs (via domestic transmission). Specifically, threonine accumulated at RT135 (RT135T) in hemophiliac and non-hemophiliac HLA-B*51:01+ individuals diagnosed before 1997, but since then RT135T has markedly declined while RT135L has increased among non-hemophiliac individuals. We demonstrated that RT135V selection by HLA-B*52:01-restricted TI8-specific T-cells led to the creation of a new HLA-C*12:02-restricted epitope TN9-8V. We further showed that TN9-8V-specific HLA-C*12:02-restricted T cells selected RT135L while TN9-8T-specific HLA-C*12:02-restricted T cells suppressed replication of the RT135T variant. Thus, population-level accumulation of the RT135L mutation over time in Japan can be explained by initial targeting of the TI8 epitope by HLA-B*52:01-restricted T-cells, followed by targeting of the resulting escape mutant by HLA-C*12:02-restricted T-cells. We further demonstrate that this phenomenon is particular to Japan, where the HLA-B*52:01-C*12:02 haplotype is common: RT135L did not accumulate over a 15-year longitudinal analysis of HIV sequences in British Columbia, Canada, where this haplotype is rare. Together, our observations reveal that T-cell responses to sequentially emerging viral escape mutants can shape long-term HIV-1 population dynamics in a host population-specific manner.


Assuntos
Variação Antigênica/imunologia , Infecções por HIV , HIV-1 , Evasão da Resposta Imune/genética , Linfócitos T Citotóxicos/imunologia , Células Cultivadas , Evolução Clonal/imunologia , Epitopos de Linfócito T/genética , Infecções por HIV/imunologia , Infecções por HIV/virologia , Soropositividade para HIV , HIV-1/classificação , HIV-1/genética , HIV-1/imunologia , Células HeLa , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Humanos , Tipagem Molecular , Mutação , Linfócitos T Citotóxicos/metabolismo , Carga Viral/imunologia , Replicação Viral/genética , Replicação Viral/imunologia
8.
Crit Care ; 24(1): 691, 2020 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-33317616

RESUMO

BACKGROUND: COVID-19 can course with respiratory and extrapulmonary disease. SARS-CoV-2 RNA is detected in respiratory samples but also in blood, stool and urine. Severe COVID-19 is characterized by a dysregulated host response to this virus. We studied whether viral RNAemia or viral RNA load in plasma is associated with severe COVID-19 and also to this dysregulated response. METHODS: A total of 250 patients with COVID-19 were recruited (50 outpatients, 100 hospitalized ward patients and 100 critically ill). Viral RNA detection and quantification in plasma was performed using droplet digital PCR, targeting the N1 and N2 regions of the SARS-CoV-2 nucleoprotein gene. The association between SARS-CoV-2 RNAemia and viral RNA load in plasma with severity was evaluated by multivariate logistic regression. Correlations between viral RNA load and biomarkers evidencing dysregulation of host response were evaluated by calculating the Spearman correlation coefficients. RESULTS: The frequency of viral RNAemia was higher in the critically ill patients (78%) compared to ward patients (27%) and outpatients (2%) (p < 0.001). Critical patients had higher viral RNA loads in plasma than non-critically ill patients, with non-survivors showing the highest values. When outpatients and ward patients were compared, viral RNAemia did not show significant associations in the multivariate analysis. In contrast, when ward patients were compared with ICU patients, both viral RNAemia and viral RNA load in plasma were associated with critical illness (OR [CI 95%], p): RNAemia (3.92 [1.183-12.968], 0.025), viral RNA load (N1) (1.962 [1.244-3.096], 0.004); viral RNA load (N2) (2.229 [1.382-3.595], 0.001). Viral RNA load in plasma correlated with higher levels of chemokines (CXCL10, CCL2), biomarkers indicative of a systemic inflammatory response (IL-6, CRP, ferritin), activation of NK cells (IL-15), endothelial dysfunction (VCAM-1, angiopoietin-2, ICAM-1), coagulation activation (D-Dimer and INR), tissue damage (LDH, GPT), neutrophil response (neutrophils counts, myeloperoxidase, GM-CSF) and immunodepression (PD-L1, IL-10, lymphopenia and monocytopenia). CONCLUSIONS: SARS-CoV-2 RNAemia and viral RNA load in plasma are associated with critical illness in COVID-19. Viral RNA load in plasma correlates with key signatures of dysregulated host responses, suggesting a major role of uncontrolled viral replication in the pathogenesis of this disease.


Assuntos
/complicações , RNA Viral/análise , Carga Viral/imunologia , Adulto , Idoso , Biomarcadores/análise , Biomarcadores/sangue , Distribuição de Qui-Quadrado , Estado Terminal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Reação em Cadeia da Polimerase/métodos , RNA Viral/sangue , Estatísticas não Paramétricas
9.
PLoS One ; 15(12): e0243625, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33382756

RESUMO

OBJECTIVES: To compare virologic and immunologic outcomes of integrase inhibitor (INSTI)-containing, contemporary boosted protease inhibitor (PI/b)-containing and non-nucleotide reverse transcriptase inhibitor (NNRTI)-containing regimens in a real-life setting. METHODS: Using logistic regression, virologic and immunologic outcomes of INSTI use were compared to outcomes of PI/b or NNRTI treatment 12 months after treatment start or switch, for participants in the RESPOND cohort consortium. A composite treatment outcome (cTO) was used, defining success as viral load (VL) <200 copies/mL and failure as at least one of: VL ≥200 copies/mL, unknown VL in the time window, any changes of antiretroviral therapy (ART) regimen, AIDS, or death. In addition, on-treatment analysis including only individuals with known VL and no regimen changes was performed. Favorable immunologic response was defined as a 25% increase in CD4 count or as reaching ≥750 CD4 cells/µL. RESULTS: Between January 2012 and January 2019, 13,703 (33.0% ART-naïve) individuals were included, of whom 7,147 started/switched to a regimen with an INSTI, 3,102 to a PI/b and 3,454 to an NNRTI-containing regimen. The main reason for cTO failure in all treatment groups were changes in ART regimen. Compared to INSTIs, the adjusted odds ratio (aOR) of cTO success was significantly lower for PI/b (0.74 [95% confidence interval, CI 0.67-0.82], p <0.001), but similar for NNRTIs (1.07 [CI 0.97-1.17], p = 0.11). On-treatment analysis and sensitivity analyses using a VL cut-off of 50 copies/mL were consistent. Compared to INSTIs, the aORs of a 25% increase in CD4 count were lower for NNRTIs (0.80 [CI 0.71-0.91], p<0.001) and PI/b (0.87 [CI 0.76-0.99], p = 0.04). CONCLUSION: In this large analysis of a real-world population, cTO and on-treatment success were similar between INSTIs and NNRTIs, but lower for PI/b, though residual confounding cannot be fully excluded. Obtaining favorable immunologic outcomes were more likely for INSTIs than the other drug classes.


Assuntos
Infecções por HIV/tratamento farmacológico , Inibidores de Integrase de HIV/uso terapêutico , Inibidores da Protease de HIV/uso terapêutico , Inibidores da Transcriptase Reversa/uso terapêutico , Adulto , Contagem de Linfócito CD4 , Estudos de Coortes , Feminino , HIV/efeitos dos fármacos , HIV/imunologia , Infecções por HIV/imunologia , Infecções por HIV/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Carga Viral/efeitos dos fármacos , Carga Viral/imunologia
10.
BMJ Case Rep ; 13(10)2020 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-33012717

RESUMO

We present a case of COVID-19 in an immunocompetent patient with risk factors for severe disease who recovered after prolonged swab positivity of 61 days postsymptom onset without significant respiratory and organ dysfunction. We discuss the reasons behind her prolonged swab positivity in the context of current SARS-CoV-2 knowledge, document the trend in her inflammatory response and swab results, and discuss the implications swab positivity had on her isolation and recovery.


Assuntos
Betacoronavirus/imunologia , Infecções por Coronavirus/imunologia , Hospedeiro Imunocomprometido/imunologia , Pneumonia Viral/imunologia , Eliminação de Partículas Virais/imunologia , Idoso , Infecções por Coronavirus/terapia , Feminino , Humanos , Pandemias , Pneumonia Viral/terapia , Tempo , Carga Viral/imunologia
11.
PLoS Comput Biol ; 16(10): e1008235, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33031368

RESUMO

Angiotensin-converting enzyme inhibitors (ACEi) and angiotensin II receptor blockers (ARB) are frequently prescribed for a range of diseases including hypertension, proteinuric chronic kidney disease, and heart failure. There is evidence indicating that these drugs upregulate ACE2, a key component of the renin-angiotensin system (RAS) and is found on the cells of a number of tissues, including the epithelial cells in the lungs. While ACE2 has a beneficial role in many diseases such as hypertension, diabetes, and cardiovascular disease, it also serves as a receptor for both SARS-CoV and SARS-CoV-2 via binding with the spike protein of the virus, thereby allowing it entry into host cells. Thus, it has been suggested that these therapies can theoretically increase the risk of SARS- CoV-2 infection and cause more severe COVID-19. Given the success of ACEi and ARBs in cardiovascular diseases, we seek to gain insights into the implications of these medications in the pathogenesis of COVID-19. To that end, we have developed a mathematical model that represents the RAS, binding of ACE2 with SARS-CoV-2 and the subsequent cell entry, and the host's acute inflammatory response. The model can simulate different levels of SARS-CoV-2 exposure, and represent the effect of commonly prescribed anti-hypertensive medications, ACEi and ARB, and predict tissue damage. Model simulations indicate that whether the extent of tissue damage may be exacerbated by ACEi or ARB treatment depends on a number of factors, including the level of existing inflammation, dosage, and the effect of the drugs on ACE2 protein abundance. The findings of this study can serve as the first step in the development of appropriate and more comprehensive guidelines for the prescription of ACEi and ARB in the current and future coronavirus pandemics.


Assuntos
Antagonistas de Receptores de Angiotensina/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Infecções por Coronavirus , Hipertensão , Modelos Biológicos , Pandemias , Pneumonia Viral , Betacoronavirus , Infecções por Coronavirus/complicações , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/fisiopatologia , Humanos , Hipertensão/complicações , Hipertensão/tratamento farmacológico , Hipertensão/fisiopatologia , Pneumonia Viral/complicações , Pneumonia Viral/imunologia , Pneumonia Viral/fisiopatologia , Carga Viral/imunologia
12.
Trials ; 21(1): 875, 2020 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-33092632

RESUMO

OBJECTIVES: The primary objective is to demonstrate that COVID-19 convalescent plasma (CCP) prevents progression to severe pneumonia in elderly COVID-19 pneumonia patients with chronic comorbidities. Secondary objectives are to demonstrate that CCP decreases the viral load in nasopharyngeal swabs and increases the anti-SARS-CoV-2 antibody titre in recipients. TRIAL DESIGN: This is a randomized, open-label, parallel group, phase II/III study with a superiority framework. The trial starts with a screening phase II designed with two-tailed alpha=0.2. In case of positive results, the trial will proceed in a formally comparative phase III (alpha=0.05). PARTICIPANTS: Adult patients with confirmed or suspected COVID-19 who are at risk according to CDC definition are eligible. Inclusion criteria are all the following: age ≥ 65; pneumonia at CT scan; PaO2/FiO2 ≥300 mmHg; presence of one or more comorbidities; signed informed consent. Exclusion criteria are one of the following: age < 65; PaO2/FiO2 < 300 mmHg; pending cardiopulmonary arrest; refusal to blood product transfusions; severe IgA deficiency; any life-threatening comorbidity or any other medical condition which, in the opinion of the investigator, makes the patient unsuitable for inclusion. The trial is being conducted at three reference COVID-19 centres in the middle of Italy. INTERVENTION AND COMPARATOR: Intervention: COVID-19 Convalescent Plasma (CCP) in addition to standard therapy. Patients receive three doses (200 ml/day on 3 consecutive days) of ABO matched CCP. Comparator: Standard therapy MAIN OUTCOMES: A. Primary outcome for Phase II: Proportion of patients without progression in severity of pulmonary disease, defined as worsening of 2 points in the ordinal scale of WHO by day 14. B. Primary outcome for Phase III: Proportion of patients without progression in severity of pulmonary disease, defined as worsening of 2 points in the ordinal scale of WHO by day 14. Secondary outcomes for Phase III: Decreased viral load on nasopharyngeal swab at days 6, 9 and 14; Decreased viremia at days 6 and 9; Increased antibody titer against SARS-CoV2 at days 30 and 60; Proportion of patients with negative of SARS-CoV2 nasopharyngeal swab at day 30; Length of hospital stay; Mortality rate at day 28; Total plasma related adverse event (day 60); Total non-plasma related adverse events (day 60); Severe adverse events (SAE) (day 60). RANDOMISATION: Treatment allocation is randomized with a ratio 1:1 in both phase II and phase III. Randomization sequences will be generated at Fondazione Policlinico Gemelli IRCCS through the RedCap web application. Randomized stratification is performed according to age (under/over 80 years), and sex. BLINDING (MASKING): None, this is an open-label trial. NUMBERS TO BE RANDOMISED (SAMPLE SIZE): Phase II: 114 patients (57 per arm). Phase III: 182 patients (91 per arm) TRIAL STATUS: The trial recruitment started on May 27, 2020. The anticipated date of recruitment completion is April 30, 2021. The protocol version is 2 (May 10, 2020). TRIAL REGISTRATION: The trial has been registered on ClinicalTrials.gov (May 5, 2020). The Identifier number is NCT04374526 FULL PROTOCOL: The full protocol is attached as an additional file, accessible from the Trials website (Additional file 1). In the interest in expediting dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol.


Assuntos
Betacoronavirus/genética , Transfusão de Sangue/métodos , Infecções por Coronavirus/terapia , Pneumonia Viral/terapia , Idoso , Idoso de 80 Anos ou mais , Betacoronavirus/imunologia , Comorbidade , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Progressão da Doença , Feminino , Humanos , Imunização Passiva/efeitos adversos , Imunização Passiva/métodos , Consentimento Livre e Esclarecido/ética , Itália/epidemiologia , Masculino , Mortalidade/tendências , Pandemias , Pneumonia/diagnóstico por imagem , Pneumonia/prevenção & controle , Pneumonia Viral/epidemiologia , Pneumonia Viral/virologia , Tomografia Computadorizada por Raios X/métodos , Carga Viral/imunologia , Carga Viral/estatística & dados numéricos
13.
Vaccine ; 38(47): 7533-7541, 2020 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-33039209

RESUMO

We developed a severe acute respiratory syndrome (SARS) subunit recombinant protein vaccine candidate based on a high-yielding, yeast-engineered, receptor-binding domain (RBD219-N1) of the SARS beta-coronavirus (SARS-CoV) spike (S) protein. When formulated with Alhydrogel®, RBD219-N1 induced high levels of neutralizing antibodies against both pseudotyped virus and a clinical (mouse-adapted) isolate of SARS-CoV. Here, we report that mice immunized with RBD219-N1/Alhydrogel® were fully protected from lethal SARS-CoV challenge (0% mortality), compared to ~30% mortality in mice immunized with the SARS S protein formulated with Alhydrogel®, and 100% mortality in negative controls. An RBD219-N1 formulation with Alhydrogel® was also superior to the S protein, unadjuvanted RBD, and AddaVax (MF59-like adjuvant)-formulated RBD in inducing specific antibodies and preventing cellular infiltrates in the lungs upon SARS-CoV challenge. Specifically, a formulation with a 1:25 ratio of RBD219-N1 to Alhydrogel® provided high neutralizing antibody titers, 100% protection with non-detectable viral loads with minimal or no eosinophilic pulmonary infiltrates. As a result, this vaccine formulation is under consideration for further development against SARS-CoV and potentially other emerging and re-emerging beta-CoVs such as SARS-CoV-2.


Assuntos
Betacoronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas de Subunidades/imunologia , Vacinas Sintéticas/imunologia , Vacinas Virais/imunologia , Hidróxido de Alumínio/administração & dosagem , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Infecções por Coronavirus/imunologia , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Domínios Proteicos/imunologia , Proteínas Recombinantes/imunologia , Síndrome Respiratória Aguda Grave/prevenção & controle , Glicoproteína da Espícula de Coronavírus/genética , Carga Viral/imunologia
14.
Front Immunol ; 11: 572635, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33123149

RESUMO

The effects of cytokine inhibition in the different phases of the severe coronavirus disease 2019 (COVID-19) are currently at the center of intense debate, and preliminary results from observational studies and case reports offer conflicting results thus far. The identification of the correct timing of administration of anti-cytokine therapies and other immunosuppressants in COVID-19 should take into account the intricate relationship between the viral burden, the hyperactivation of the innate immune system and the adaptive immune dysfunction. The main challenge for effective administration of anti-cytokine therapy in COVID-19 will be therefore to better define a precise "window of therapeutic opportunity." Only considering a more specific set of criteria able to integrate information on direct viral damage, the cytokine burden, and the patient's immune vulnerability, it will be possible to decide, carefully balancing both benefits and risks, the appropriateness of using immunosuppressive drugs even in patients affected primarily by an infectious disease.


Assuntos
Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/imunologia , Citocinas/antagonistas & inibidores , Imunossupressores/uso terapêutico , Imunoterapia/métodos , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/imunologia , Betacoronavirus/efeitos dos fármacos , Betacoronavirus/imunologia , Infecções por Coronavirus/patologia , Humanos , Pandemias , Pneumonia Viral/patologia , Carga Viral/imunologia
15.
Cell Mol Immunol ; 17(10): 1098-1100, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32939033
16.
Zool Res ; 41(5): 503-516, 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-32772513

RESUMO

As of June 2020, Coronavirus Disease 2019 (COVID-19) has killed an estimated 440 000 people worldwide, 74% of whom were aged ≥65 years, making age the most significant risk factor for death caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. To examine the effect of age on death, we established a SARS-CoV-2 infection model in Chinese rhesus macaques ( Macaca mulatta) of varied ages. Results indicated that infected young macaques manifested impaired respiratory function, active viral replication, severe lung damage, and infiltration of CD11b + and CD8 + cells in lungs at one-week post infection (wpi), but also recovered rapidly at 2 wpi. In contrast, aged macaques demonstrated delayed immune responses with a more severe cytokine storm, increased infiltration of CD11b + cells, and persistent infiltration of CD8 + cells in the lungs at 2 wpi. In addition, peripheral blood T cells from aged macaques showed greater inflammation and chemotaxis, but weaker antiviral functions than that in cells from young macaques. Thus, the delayed but more severe cytokine storm and higher immune cell infiltration may explain the poorer prognosis of older aged patients suffering SARS-CoV-2 infection.


Assuntos
Envelhecimento/imunologia , Betacoronavirus/imunologia , Infecções por Coronavirus/imunologia , Citocinas/imunologia , Macaca mulatta/imunologia , Pneumonia Viral/imunologia , Linfócitos T/imunologia , Fatores Etários , Envelhecimento/metabolismo , Animais , Betacoronavirus/fisiologia , Infecções por Coronavirus/veterinária , Infecções por Coronavirus/virologia , Citocinas/metabolismo , Inflamação/imunologia , Inflamação/veterinária , Inflamação/virologia , Pulmão/imunologia , Pulmão/patologia , Pulmão/virologia , Macaca mulatta/virologia , Doenças dos Macacos/imunologia , Doenças dos Macacos/virologia , Pandemias/veterinária , Pneumonia Viral/veterinária , Pneumonia Viral/virologia , Síndrome Respiratória Aguda Grave/imunologia , Síndrome Respiratória Aguda Grave/veterinária , Síndrome Respiratória Aguda Grave/virologia , Linfócitos T/metabolismo , Linfócitos T/patologia , Carga Viral/imunologia , Carga Viral/veterinária , Replicação Viral/imunologia
17.
PLoS Pathog ; 16(8): e1008743, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32760128

RESUMO

Arthritogenic alphaviruses cause debilitating musculoskeletal disease and historically have circulated in distinct regions. With the global spread of chikungunya virus (CHIKV), there now is more geographic overlap, which could result in heterologous immunity affecting natural infection or vaccination. Here, we evaluated the capacity of a cross-reactive anti-CHIKV monoclonal antibody (CHK-265) to protect against disease caused by the distantly related alphavirus, Ross River virus (RRV). Although CHK-265 only moderately neutralizes RRV infection in cell culture, it limited clinical disease in mice independently of Fc effector function activity. Despite this protective phenotype, RRV escaped from CHK-265 neutralization in vivo, with resistant variants retaining pathogenic potential. Near the inoculation site, CHK-265 reduced viral burden in a type I interferon signaling-dependent manner and limited immune cell infiltration into musculoskeletal tissue. In a parallel set of experiments, purified human CHIKV immune IgG also weakly neutralized RRV, yet when transferred to mice, resulted in improved clinical outcome during RRV infection despite the emergence of resistant viruses. Overall, this study suggests that weakly cross-neutralizing antibodies can protect against heterologous alphavirus disease, even if neutralization escape occurs, through an early viral control program that tempers inflammation.


Assuntos
Infecções por Alphavirus/complicações , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Reações Cruzadas/imunologia , Doenças Musculoesqueléticas/prevenção & controle , Vírus do Rio Ross/isolamento & purificação , Carga Viral/imunologia , Infecções por Alphavirus/virologia , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Doenças Musculoesqueléticas/imunologia , Doenças Musculoesqueléticas/virologia , Receptores Fc/fisiologia , Vírus do Rio Ross/imunologia , Virulência
18.
Clin Immunol ; 218: 108524, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32659373

RESUMO

The outbreak of SARS-CoV-2-associated pneumonia, a disease called COVID-19, has caused a pandemic worldwide. To investigate the immune responses after infection of SARS-CoV-2 in non-critical patients may help to better understand the disease progression. We collected 334 confirmed COVID-19 cases including 212 still in hospital with nucleic acid test positive on halfway for SARS-CoV-2 and 122 discharged from hospital, compared specific antibodies, immune cells, and cytokine changes between the hospitalized and discharged patients. The hospitalized patients had a longer illness time compared with discharged patients. Analysis of viral loads explained long-term or persistent infection of SARS-CoV-2, which existed with the median time of 18.5 days of the positive nucleic acid test. Serum analysis showed that the specific anti-N IgG antibody was positive in all detected patients after infection of two weeks. Neutrophils, Monocytes, NK cells, and CD4+ T cells significantly increased, while total lymphocytes and CD8+ T cells decreased from non-critical hospitalized patients after longer-term infection. Further analysis of the cytokines showed that IL-6, TNF-α, IFN-γ, IL-2, IL-4, and IL-10 from the hospitalized patients were significantly higher, indicating a potential of the increased CD4+ T cell differentiation.


Assuntos
Betacoronavirus/patogenicidade , Doenças Cardiovasculares/imunologia , Infecções por Coronavirus/imunologia , Diabetes Mellitus/imunologia , Imunidade Inata , Pneumopatias/imunologia , Neoplasias/imunologia , Pneumonia Viral/imunologia , Idoso , Anticorpos Antivirais/sangue , Betacoronavirus/imunologia , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/patologia , Doenças Cardiovasculares/virologia , China/epidemiologia , Comorbidade , Convalescença , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/patologia , Infecções por Coronavirus/virologia , Citocinas/sangue , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/patologia , Diabetes Mellitus/virologia , Feminino , Hospitalização , Humanos , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/patologia , Células Matadoras Naturais/virologia , Pneumopatias/epidemiologia , Pneumopatias/patologia , Pneumopatias/virologia , Subpopulações de Linfócitos/imunologia , Subpopulações de Linfócitos/patologia , Subpopulações de Linfócitos/virologia , Masculino , Pessoa de Meia-Idade , Monócitos/imunologia , Monócitos/patologia , Monócitos/virologia , Neoplasias/epidemiologia , Neoplasias/patologia , Neoplasias/virologia , Neutrófilos/imunologia , Neutrófilos/patologia , Neutrófilos/virologia , Pandemias , Alta do Paciente , Pneumonia Viral/epidemiologia , Pneumonia Viral/patologia , Pneumonia Viral/virologia , Fatores de Tempo , Carga Viral/imunologia
19.
Nat Commun ; 11(1): 3736, 2020 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-32719371

RESUMO

A replication-competent vesicular stomatitis virus vaccine expressing the Ebola virus (EBOV) glycoprotein (GP) (rVSV-ZEBOV) was successfully used during the 2013-16 EBOV epidemic. Additionally, chimeric and human monoclonal antibodies (mAb) against the EBOV GP have shown promise in animals and humans when administered therapeutically. Uncertainty exists regarding the efficacy of postexposure antibody treatments in the event of a known exposure of a recent rVSV-ZEBOV vaccinee. Here, we model a worst-case scenario using rhesus monkeys vaccinated or unvaccinated with the rVSV-ZEBOV vaccine. We demonstrate that animals challenged with a uniformly lethal dose of EBOV one day following vaccination, and then treated with the anti-EBOV GP mAb MIL77 starting 3 days postexposure show no evidence of clinical illness and survive challenge. In contrast, animals receiving only vaccination or only mAb-based therapy become ill, with decreased survival compared to animals vaccinated and subsequently treated with MIL77. These results suggest that rVSV-ZEBOV augments immunotherapy.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Anticorpos Antivirais/uso terapêutico , Vacinas contra Ebola/imunologia , Doença pelo Vírus Ebola/imunologia , Doença pelo Vírus Ebola/prevenção & controle , Profilaxia Pós-Exposição , Vacinação , Vírus da Estomatite Vesicular Indiana/imunologia , Animais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/administração & dosagem , Anticorpos Antivirais/imunologia , Doença pelo Vírus Ebola/patologia , Doença pelo Vírus Ebola/virologia , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Estimativa de Kaplan-Meier , Macaca mulatta , Resultado do Tratamento , Carga Viral/imunologia
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