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1.
Front Immunol ; 12: 614436, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33790892

RESUMEN

The novel coronavirus named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused a global pandemic of the coronavirus disease 2019 (COVID-19), which elicits a wide variety of symptoms, ranging from mild to severe, with the potential to lead to death. Although used as the standard method to screen patients for SARS-CoV-2 infection, real-time PCR has challenges in dealing with asymptomatic patients and those with an undetectable viral load. Serological tests are therefore considered potent diagnostic tools to complement real-time PCR-based diagnosis and are used for surveillance of seroprevalence in populations. However, the dynamics of the antibody response against SARS-CoV-2 currently remain to be investigated. Here, through analysis of plasma samples from 84 patients with COVID-19, we observed that the response of virus-specific antibodies against three important antigens, RBD, N and S, dynamically changed over time and reached a peak 5-8 weeks after the onset of symptoms. The antibody responses were irrespective of sex. Severe cases were found to have higher levels of antibody response, larger numbers of inflammatory cells and C-reactive protein levels. Within the mild/moderate cases, pairwise comparison indicated moderate association between anti-RBD vs. anti-N, anti-RBD vs. anti-S1S2, and anti-N vs. anti-S1S2. Furthermore, the majority of cases could achieve IgM and IgG seroconversion at 2 weeks since the disease onset. Analysis of neutralizing antibodies indicated that these responses were able to last for more than 112 days but decline significantly after the peak. In summary, our findings demonstrate the longitudinally dynamic changes in antibody responses against SARS-CoV-2, which can contribute to the knowledge of humoral immune response after SARS-CoV-2 infection and are informative for future development of vaccine and antibody-based therapies.


Asunto(s)
Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , /inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Adulto , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Beijing , China , Femenino , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Masculino , Persona de Mediana Edad , Fosfoproteínas/inmunología , Dominios Proteicos/inmunología , Seroconversión , Índice de Severidad de la Enfermedad , Centros de Atención Terciaria
2.
Science ; 372(6537)2021 04 02.
Artículo en Inglés | MEDLINE | ID: mdl-33795432

RESUMEN

Multivalent display of receptor-engaging antibodies or ligands can enhance their activity. Instead of achieving multivalency by attachment to preexisting scaffolds, here we unite form and function by the computational design of nanocages in which one structural component is an antibody or Fc-ligand fusion and the second is a designed antibody-binding homo-oligomer that drives nanocage assembly. Structures of eight nanocages determined by electron microscopy spanning dihedral, tetrahedral, octahedral, and icosahedral architectures with 2, 6, 12, and 30 antibodies per nanocage, respectively, closely match the corresponding computational models. Antibody nanocages targeting cell surface receptors enhance signaling compared with free antibodies or Fc-fusions in death receptor 5 (DR5)-mediated apoptosis, angiopoietin-1 receptor (Tie2)-mediated angiogenesis, CD40 activation, and T cell proliferation. Nanocage assembly also increases severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pseudovirus neutralization by α-SARS-CoV-2 monoclonal antibodies and Fc-angiotensin-converting enzyme 2 (ACE2) fusion proteins.


Asunto(s)
Anticuerpos/química , Anticuerpos/inmunología , Nanoestructuras , Ingeniería de Proteínas , Transducción de Señal , Angiopoyetinas/química , Angiopoyetinas/inmunología , Angiopoyetinas/metabolismo , Anticuerpos Monoclonales/química , Anticuerpos Monoclonales/inmunología , Anticuerpos Neutralizantes/química , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/química , Anticuerpos Antivirales/inmunología , Linfocitos B/inmunología , Antígenos CD40/química , Antígenos CD40/inmunología , Antígenos CD40/metabolismo , Línea Celular Tumoral , Proliferación Celular , Simulación por Computador , Genes Sintéticos , Humanos , Fragmentos Fc de Inmunoglobulinas/química , Activación de Linfocitos , Modelos Moleculares , Unión Proteica , Receptor TIE-2/metabolismo , Receptores del Ligando Inductor de Apoptosis Relacionado con TNF/inmunología , Receptores del Ligando Inductor de Apoptosis Relacionado con TNF/metabolismo , Linfocitos T/inmunología , Linfocitos T/fisiología
3.
Medicina (Kaunas) ; 57(3)2021 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-33804646

RESUMEN

Reverse transcriptase polymerase chain reaction (RT-PCR) negative results in the upper respiratory tract represent a major concern for the clinical management of coronavirus disease 2019 (COVID-19) patients. Herein, we report the case of a 43-years-old man with a strong clinical suspicion of COVID-19, who resulted in being negative to multiple severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RT-PCR tests performed on different oropharyngeal and nasopharyngeal swabs, despite serology having confirmed the presence of SARS-CoV-2 IgM. The patient underwent a chest computed tomography (CT) that showed typical imaging findings of COVID-19 pneumonia. The presence of viral SARS-CoV-2 was confirmed only by performing a SARS-CoV-2 RT-PCR test on stool. Performing of SARS-CoV-2 RT-PCR test on fecal samples can be a rapid and useful approach to confirm COVID-19 diagnosis in cases where there is an apparent discrepancy between COVID-19 clinical symptoms coupled with chest CT and SARS-CoV-2 RT-PCR tests' results on samples from the upper respiratory tract.


Asunto(s)
/diagnóstico , Heces/química , Pulmón/diagnóstico por imagen , Nasofaringe/química , Orofaringe/química , ARN Viral/aislamiento & purificación , Adulto , Anticuerpos Antivirales/inmunología , Reacciones Falso Negativas , Heces/virología , Humanos , Inmunoglobulina M/inmunología , Masculino , Nasofaringe/virología , Orofaringe/virología , Manejo de Especímenes , Tomografía Computarizada por Rayos X
4.
Euro Surveill ; 26(13)2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33797390

RESUMEN

BackgroundChildren have a low rate of COVID-19 and secondary severe multisystem inflammatory syndrome (MIS) but present a high prevalence of symptomatic seasonal coronavirus infections.AimWe tested if prior infections by seasonal coronaviruses (HCoV) NL63, HKU1, 229E or OC43 as assessed by serology, provide cross-protective immunity against SARS-CoV-2 infection.MethodsWe set a cross-sectional observational multicentric study in pauci- or asymptomatic children hospitalised in Paris during the first wave for reasons other than COVID (hospitalised children (HOS), n = 739) plus children presenting with MIS (n = 36). SARS-CoV-2 antibodies directed against the nucleoprotein (N) and S1 and S2 domains of the spike (S) proteins were monitored by an in-house luciferase immunoprecipitation system assay. We randomly selected 69 SARS-CoV-2-seropositive patients (including 15 with MIS) and 115 matched SARS-CoV-2-seronegative patients (controls (CTL)). We measured antibodies against SARS-CoV-2 and HCoV as evidence for prior corresponding infections and assessed if SARS-CoV-2 prevalence of infection and levels of antibody responses were shaped by prior seasonal coronavirus infections.ResultsPrevalence of HCoV infections were similar in HOS, MIS and CTL groups. Antibody levels against HCoV were not significantly different in the three groups and were not related to the level of SARS-CoV-2 antibodies in the HOS and MIS groups. SARS-CoV-2 antibody profiles were different between HOS and MIS children.ConclusionPrior infection by seasonal coronaviruses, as assessed by serology, does not interfere with SARS-CoV-2 infection and related MIS in children.


Asunto(s)
Anticuerpos Antivirales/inmunología , Coronavirus Humano OC43 , Síndrome de Respuesta Inflamatoria Sistémica , Adolescente , Anticuerpos Antivirales/sangre , /diagnóstico , Niño , Preescolar , Estudios Transversales , Femenino , Francia/epidemiología , Humanos , Lactante , Recién Nacido , Masculino , Paris , Estaciones del Año , Pruebas Serológicas/métodos , Glicoproteína de la Espiga del Coronavirus
5.
Nat Commun ; 12(1): 2037, 2021 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-33795692

RESUMEN

The hallmarks of COVID-19 are higher pathogenicity and mortality in the elderly compared to children. Examining baseline SARS-CoV-2 cross-reactive immunological responses, induced by circulating human coronaviruses (hCoVs), is needed to understand such divergent clinical outcomes. Here we show analysis of coronavirus antibody responses of pre-pandemic healthy children (n = 89), adults (n = 98), elderly (n = 57), and COVID-19 patients (n = 50) by systems serology. Moderate levels of cross-reactive, but non-neutralizing, SARS-CoV-2 antibodies are detected in pre-pandemic healthy individuals. SARS-CoV-2 antigen-specific Fcγ receptor binding accurately distinguishes COVID-19 patients from healthy individuals, suggesting that SARS-CoV-2 infection induces qualitative changes to antibody Fc, enhancing Fcγ receptor engagement. Higher cross-reactive SARS-CoV-2 IgA and IgG are observed in healthy elderly, while healthy children display elevated SARS-CoV-2 IgM, suggesting that children have fewer hCoV exposures, resulting in less-experienced but more polyreactive humoral immunity. Age-dependent analysis of COVID-19 patients, confirms elevated class-switched antibodies in elderly, while children have stronger Fc responses which we demonstrate are functionally different. These insights will inform COVID-19 vaccination strategies, improved serological diagnostics and therapeutics.


Asunto(s)
Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Formación de Anticuerpos/inmunología , /inmunología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , /inmunología , Niño , Preescolar , Reacciones Cruzadas/inmunología , Humanos , Inmunoglobulina A/sangre , Inmunoglobulina A/inmunología , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Inmunoglobulina M/sangre , Inmunoglobulina M/inmunología , Persona de Mediana Edad , Receptores de IgG/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Adulto Joven
6.
Nat Commun ; 12(1): 1722, 2021 03 19.
Artículo en Inglés | MEDLINE | ID: mdl-33741916

RESUMEN

Broadly neutralizing antibodies (bnAbs) have been developed as potential countermeasures for seasonal and pandemic influenza. Deep characterization of these bnAbs and polyclonal sera provides pivotal understanding for influenza immunity and informs effective vaccine design. However, conventional virus neutralization assays require high-containment laboratories and are difficult to standardize and roboticize. Here, we build a panel of engineered influenza viruses carrying a reporter gene to replace an essential viral gene, and develop an assay using the panel for in-depth profiling of neutralizing antibodies. Replication of these viruses is restricted to cells expressing the missing viral gene, allowing it to be manipulated in a biosafety level 2 environment. We generate the neutralization profile of 24 bnAbs using a 55-virus panel encompassing the near-complete diversity of human H1N1 and H3N2, as well as pandemic subtype viruses. Our system offers in-depth profiling of influenza immunity, including the antibodies against the hemagglutinin stem, a major target of universal influenza vaccines.


Asunto(s)
Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Virus de la Influenza A/inmunología , Gripe Humana/virología , Antígenos Virales/inmunología , Perfilación de la Expresión Génica , Glicoproteínas Hemaglutininas del Virus de la Influenza/genética , Glicoproteínas Hemaglutininas del Virus de la Influenza/inmunología , Hemaglutininas , Humanos , Inmunidad , Subtipo H1N1 del Virus de la Influenza A/inmunología , Subtipo H3N2 del Virus de la Influenza A/inmunología , Virus de la Influenza A/genética , Vacunas contra la Influenza/inmunología , Infecciones por Orthomyxoviridae/virología , Filogenia
7.
Front Immunol ; 12: 632814, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33763078

RESUMEN

Increasing evidence suggests that dysregulated immune responses are associated with the clinical outcome of coronavirus disease 2019 (COVID-19). Nucleocapsid protein (NP)-, spike (S)-, receptor binding domain (RBD)- specific immunoglobulin (Ig) isotypes, IgG subclasses and neutralizing antibody (NAb) were analyzed in 123 serum from 63 hospitalized patients with severe, moderate, mild or asymptomatic COVID-19. Mild to modest correlations were found between disease severity and antigen specific IgG subclasses in serum, of which IgG1 and IgG3 were negatively associated with viral load in nasopharyngeal swab. Multiple cytokines were significantly related with antigen-specific Ig isotypes and IgG subclasses, and IL-1ß was positively correlated with most antibodies. Furthermore, the old patients (≥ 60 years old) had higher levels of chemokines, increased NAb activities and SARS-CoV-2 specific IgG1, and IgG3 responses and compromised T cell responses compared to the young patients (≤ 18 years old), which are related with more severe cases. Higher IgG1 and IgG3 were found in COVID-19 patients with comorbidities while biological sex had no effect on IgG subclasses. Overall, we have identified diseases severity was related to higher antibodies, of which IgG subclasses had weakly negative correlation with viral load, and cytokines were significantly associated with antibody response. Further, advancing age and comorbidities had obvious effect on IgG1 and IgG3.


Asunto(s)
Anticuerpos Antivirales/inmunología , Inmunoglobulina G/inmunología , /fisiología , Adolescente , Adulto , /virología , Niño , China , Citocinas/inmunología , Femenino , Humanos , Inmunoglobulina A/inmunología , Inmunoglobulina M/inmunología , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Linfocitos T/inmunología , Adulto Joven
8.
Sci Rep ; 11(1): 5558, 2021 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-33692386

RESUMEN

The recent COVID-19 pandemic poses a serious threat to global public health, thus there is an urgent need to define the molecular mechanisms involved in SARS-CoV-2 spike (S) protein-mediated virus entry that is essential for preventing and/or treating this emerging infectious disease. In this study, we examined the blocking activity of human COVID-19 convalescent plasma by cell-cell fusion assays using SARS-CoV-2-S-transfected 293 T as effector cells and ACE2-expressing 293 T as target cells. We demonstrate that the SARS-CoV-2 S protein exhibits a very high capacity for membrane fusion and is efficient in mediating virus fusion and entry into target cells. Importantly, we find that COVID-19 convalescent plasma with high titers of IgG neutralizing antibodies can block cell-cell fusion and virus entry by interfering with the SARS-CoV-2-S/ACE2 or SARS-CoV-S/ACE2 interactions. These findings suggest that COVID-19 convalescent plasma may not only inhibit SARS-CoV-2-S but also cross-neutralize SARS-CoV-S-mediated membrane fusion and virus entry, supporting its potential as a preventive and/or therapeutic agent against SARS-CoV-2 as well as other SARS-CoV infections.


Asunto(s)
/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Adulto , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Fusión Celular/métodos , Femenino , Humanos , Inmunización Pasiva/métodos , Masculino , Fusión de Membrana/efectos de los fármacos , Persona de Mediana Edad , Pandemias/prevención & control , Plasma/química , Receptores Virales/metabolismo , /patogenicidad , Glicoproteína de la Espiga del Coronavirus/metabolismo , Internalización del Virus/efectos de los fármacos
9.
Sci Rep ; 11(1): 5538, 2021 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-33692390

RESUMEN

Understanding antibody responses to SARS-CoV-2 is indispensable for the development of containment measures to overcome the current COVID-19 pandemic. Recent studies showed that serum from convalescent patients can display variable neutralization capacities. Still, it remains unclear whether there are specific signatures that can be used to predict neutralization. Here, we performed a detailed analysis of sera from a cohort of 101 recovered healthcare workers and we addressed their SARS-CoV-2 antibody response by ELISA against SARS-CoV-2 Spike receptor binding domain and nucleoprotein. Both ELISA methods detected sustained levels of serum IgG against both antigens. Yet, the majority of individuals from our cohort generated antibodies with low neutralization capacity and only 6% showed high neutralizing titers against both authentic SARS-CoV-2 virus and the Spike pseudotyped virus. Interestingly, higher neutralizing sera correlate with detection of -IgG, IgM and IgA antibodies against both antigens, while individuals with positive IgG alone showed poor neutralization response. These results suggest that having a broader repertoire of antibodies may contribute to more potent SARS-CoV-2 neutralization. Altogether, our work provides a cross sectional snapshot of the SARS-CoV-2 neutralizing antibody response in recovered healthcare workers and provides preliminary evidence that possessing multiple antibody isotypes can play an important role in predicting SARS-CoV-2 neutralization.


Asunto(s)
Anticuerpos Neutralizantes/inmunología , /inmunología , Adulto , Anticuerpos Antivirales/inmunología , Estudios de Cohortes , Estudios Transversales , Ensayo de Inmunoadsorción Enzimática/métodos , Epítopos/inmunología , Femenino , Humanos , Inmunoglobulina A/sangre , Inmunoglobulina G/sangre , Masculino , Pruebas de Neutralización/métodos , Pandemias , Suero/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología
10.
Sci Rep ; 11(1): 5563, 2021 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-33692457

RESUMEN

While there are various attempts to administer COVID-19-convalescent plasmas to SARS-CoV-2-infected patients, neither appropriate approach nor clinical utility has been established. We examined the presence and temporal changes of the neutralizing activity of IgG fractions from 43 COVID-19-convalescent plasmas using cell-based assays with multiple endpoints. IgG fractions from 27 cases (62.8%) had significant neutralizing activity and moderately to potently inhibited SARS-CoV-2 infection in cell-based assays; however, no detectable neutralizing activity was found in 16 cases (37.2%). Approximately half of the patients (~ 41%), who had significant neutralizing activity, lost the neutralization activity within ~ 1 month. Despite the rapid decline of neutralizing activity in plasmas, good amounts of SARS-CoV-2-S1-binding antibodies were persistently seen. The longer exposure of COVID-19 patients to greater amounts of SARS-CoV-2 elicits potent immune response to SARS-CoV-2, producing greater neutralization activity and SARS-CoV-2-S1-binding antibody amounts. The dilution of highly-neutralizing plasmas with poorly-neutralizing plasmas relatively readily reduced neutralizing activity. The presence of good amounts of SARS-CoV-2-S1-binding antibodies does not serve as a surrogate ensuring the presence of good neutralizing activity. In selecting good COVID-19-convalescent plasmas, quantification of neutralizing activity in each plasma sample before collection and use is required.


Asunto(s)
/inmunología , Inmunoglobulina G/inmunología , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Femenino , Humanos , Inmunización Pasiva/métodos , Masculino , Persona de Mediana Edad , Pandemias/prevención & control , Plasma/química , Receptores Virales/metabolismo , /patogenicidad
11.
EBioMedicine ; 65: 103259, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33662833

RESUMEN

BACKGROUND: SARS-CoV-2 serology is used to identify prior infection at individual and at population level. Extended longitudinal studies with multi-timepoint sampling to evaluate dynamic changes in antibody levels are required to identify the time horizon in which these applications of serology are valid, and to explore the longevity of protective humoral immunity. METHODS: Healthcare workers were recruited to a prospective cohort study from the first SARS-CoV-2 epidemic peak in London, undergoing weekly symptom screen, viral PCR and blood sampling over 16-21 weeks. Serological analysis (n =12,990) was performed using semi-quantitative Euroimmun IgG to viral spike S1 domain and Roche total antibody to viral nucleocapsid protein (NP) assays. Comparisons were made to pseudovirus neutralizing antibody measurements. FINDINGS: A total of 157/729 (21.5%) participants developed positive SARS-CoV-2 serology by one or other assay, of whom 31.0% were asymptomatic and there were no deaths. Peak Euroimmun anti-S1 and Roche anti-NP measurements correlated (r = 0.57, p<0.0001) but only anti-S1 measurements correlated with near-contemporary pseudovirus neutralising antibody titres (measured at 16-18 weeks, r = 0.57, p<0.0001). By 21 weeks' follow-up, 31/143 (21.7%) anti-S1 and 6/150 (4.0%) anti-NP measurements reverted to negative. Mathematical modelling revealed faster clearance of anti-S1 compared to anti-NP (median half-life of 2.5 weeks versus 4.0 weeks), earlier transition to lower levels of antibody production (median of 8 versus 13 weeks), and greater reductions in relative antibody production rate after the transition (median of 35% versus 50%). INTERPRETATION: Mild SARS-CoV-2 infection is associated with heterogeneous serological responses in Euroimmun anti-S1 and Roche anti-NP assays. Anti-S1 responses showed faster rates of clearance, more rapid transition from high to low level production rate and greater reduction in production rate after this transition. In mild infection, anti-S1 serology alone may underestimate incident infections. The mechanisms that underpin faster clearance and lower rates of sustained anti-S1 production may impact on the longevity of humoral immunity. FUNDING: Charitable donations via Barts Charity, Wellcome Trust, NIHR.


Asunto(s)
Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , /inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Personal de Salud/estadística & datos numéricos , Humanos , Inmunoglobulina A/sangre , Inmunoglobulina G/sangre , Fosfoproteínas/inmunología , Dominios Proteicos/inmunología
12.
Curr Microbiol ; 78(4): 1124-1134, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33687511

RESUMEN

Phage display is one of the important and effective molecular biology techniques and has remained indispensable for research community since its discovery in the year 1985. As a large number of nucleotide fragments may be cloned into the phage genome, a phage library may harbour millions or sometimes billions of unique and distinctive displayed peptide ligands. The ligand-receptor interactions forming the basis of phage display have been well utilized in epitope mapping and antigen presentation on the surface of bacteriophages for screening novel vaccine candidates by using affinity selection-based strategy called biopanning. This versatile technique has been modified tremendously over last three decades, leading to generation of different platforms for combinatorial peptide display. The translation of new diagnostic tools thus developed has been used in situations arising due to pathogenic microbes, including bacteria and deadly viruses, such as Zika, Ebola, Hendra, Nipah, Hanta, MERS and SARS. In the current situation of pandemic of Coronavirus disease (COVID-19), a search for neutralizing antibodies is motivating the researchers to find therapeutic candidates against novel SARS-CoV-2. As phage display is an important technique for antibody selection, this review presents a concise summary of the very recent applications of phage display technique with a special reference to progress in diagnostics and therapeutics for coronavirus diseases. Hopefully, this technique can complement studies on host-pathogen interactions and assist novel strategies of drug discovery for coronaviruses.


Asunto(s)
Anticuerpos Antivirales/inmunología , Técnicas de Visualización de Superficie Celular/métodos , /inmunología , Anticuerpos Neutralizantes/inmunología , Bacteriófago M13/genética , Bacteriófago M13/metabolismo , Bacteriófago T4/genética , Bacteriófago T4/metabolismo , Bacteriófago T7/genética , Bacteriófago T7/metabolismo , Escherichia coli/genética , Escherichia coli/virología , Humanos
13.
Emerg Microbes Infect ; 10(1): 629-637, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33691606

RESUMEN

COVID-19 vaccines emerging from different platforms differ in efficacy, duration of protection, and side effects. To maximize the benefits of vaccination, we explored the utility of employing a heterologous prime-boost strategy in which different combinations of the four types of leading COVID-19 vaccine candidates that are undergoing clinical trials in China were tested in a mouse model. Our results showed that sequential immunization with adenovirus vectored vaccine followed by inactivated/recombinant subunit/mRNA vaccine administration specifically increased levels of neutralizing antibodies and promoted the modulation of antibody responses to predominantly neutralizing antibodies. Moreover, a heterologous prime-boost regimen with an adenovirus vector vaccine also improved Th1-biased T cell responses. Our results provide new ideas for the development and application of COVID-19 vaccines to control the SARS-CoV-2 pandemic.


Asunto(s)
Vacunas contra el Adenovirus/inmunología , Anticuerpos Antivirales/sangre , Inmunización Secundaria/métodos , Vacunas de Subunidad/inmunología , Vacunas Sintéticas/inmunología , Vacunas contra el Adenovirus/administración & dosificación , Animales , Anticuerpos Neutralizantes/sangre , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , /efectos adversos , Interferón gamma/sangre , Recuento de Linfocitos , Ratones , Ratones Endogámicos BALB C , Linfocitos T/inmunología , Linfocitos T Colaboradores-Inductores/inmunología , Vacunación/efectos adversos , Vacunas de Subunidad/administración & dosificación , Vacunas Sintéticas/administración & dosificación
14.
Biosens Bioelectron ; 180: 113112, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33706158

RESUMEN

Infectious diseases caused by viruses can elevate up to undesired pandemic conditions affecting the global population and normal life function. These in turn impact the established world economy, create jobless situations, physical, mental, emotional stress, and challenge the human survival. Therefore, timely detection, treatment, isolation and prevention of spreading the pandemic infectious diseases not beyond the originated town is critical to avoid global impairment of life (e.g., Corona virus disease - 2019, COVID-19). The objective of this review article is to emphasize the recent advancements in the electrochemical diagnostics of twelve life-threatening viruses namely - COVID-19, Middle east respiratory syndrome (MERS), Severe acute respiratory syndrome (SARS), Influenza, Hepatitis, Human immunodeficiency virus (HIV), Human papilloma virus (HPV), Zika virus, Herpes simplex virus, Chikungunya, Dengue, and Rotavirus. This review describes the design, principle, underlying rationale, receptor, and mechanistic aspects of sensor systems reported for such viruses. Electrochemical sensor systems which comprised either antibody or aptamers or direct/mediated electron transfer in the recognition matrix were explicitly segregated into separate sub-sections for critical comparison. This review emphasizes the current challenges involved in translating laboratory research to real-world device applications, future prospects and commercialization aspects of electrochemical diagnostic devices for virus detection. The background and overall progress provided in this review are expected to be insightful to the researchers in sensor field and facilitate the design and fabrication of electrochemical sensors for life-threatening viruses with broader applicability to any desired pathogens.


Asunto(s)
Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Virosis/diagnóstico , Anticuerpos Antivirales/inmunología , Humanos , Técnicas Analíticas Microfluídicas , Técnica SELEX de Producción de Aptámeros
15.
Proc Natl Acad Sci U S A ; 118(12)2021 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-33688034

RESUMEN

The current pandemic of COVID-19 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) highlights an urgent need to develop a safe, efficacious, and durable vaccine. Using a measles virus (rMeV) vaccine strain as the backbone, we developed a series of recombinant attenuated vaccine candidates expressing various forms of the SARS-CoV-2 spike (S) protein and its receptor binding domain (RBD) and evaluated their efficacy in cotton rat, IFNAR-/-mice, IFNAR-/--hCD46 mice, and golden Syrian hamsters. We found that rMeV expressing stabilized prefusion S protein (rMeV-preS) was more potent in inducing SARS-CoV-2-specific neutralizing antibodies than rMeV expressing full-length S protein (rMeV-S), while the rMeVs expressing different lengths of RBD (rMeV-RBD) were the least potent. Animals immunized with rMeV-preS produced higher levels of neutralizing antibody than found in convalescent sera from COVID-19 patients and a strong Th1-biased T cell response. The rMeV-preS also provided complete protection of hamsters from challenge with SARS-CoV-2, preventing replication in lungs and nasal turbinates, body weight loss, cytokine storm, and lung pathology. These data demonstrate that rMeV-preS is a safe and highly efficacious vaccine candidate, supporting its further development as a SARS-CoV-2 vaccine.


Asunto(s)
/inmunología , Vectores Genéticos , Virus del Sarampión , Glicoproteína de la Espiga del Coronavirus/inmunología , Vacunas Sintéticas/inmunología , Animales , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , /patología , Cricetinae , Modelos Animales de Enfermedad , Expresión Génica , Vectores Genéticos/genética , Vectores Genéticos/inmunología , Humanos , Inmunización , Inmunogenicidad Vacunal , Virus del Sarampión/genética , Virus del Sarampión/inmunología , Ratones , Ratones Transgénicos , Ratas , Glicoproteína de la Espiga del Coronavirus/genética , Vacunas Sintéticas/genética
16.
Proc Natl Acad Sci U S A ; 118(12)2021 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-33688035

RESUMEN

Modified vaccinia virus Ankara (MVA) is a replication-restricted smallpox vaccine, and numerous clinical studies of recombinant MVAs (rMVAs) as vectors for prevention of other infectious diseases, including COVID-19, are in progress. Here, we characterize rMVAs expressing the S protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Modifications of full-length S individually or in combination included two proline substitutions, mutations of the furin recognition site, and deletion of the endoplasmic retrieval signal. Another rMVA in which the receptor binding domain (RBD) is flanked by the signal peptide and transmembrane domains of S was also constructed. Each modified S protein was displayed on the surface of rMVA-infected cells and was recognized by anti-RBD antibody and soluble hACE2 receptor. Intramuscular injection of mice with the rMVAs induced antibodies, which neutralized a pseudovirus in vitro and, upon passive transfer, protected hACE2 transgenic mice from lethal infection with SARS-CoV-2, as well as S-specific CD3+CD8+IFNγ+ T cells. Antibody boosting occurred following a second rMVA or adjuvanted purified RBD protein. Immunity conferred by a single vaccination of hACE2 mice prevented morbidity and weight loss upon intranasal infection with SARS-CoV-2 3 wk or 7 wk later. One or two rMVA vaccinations also prevented detection of infectious SARS-CoV-2 and subgenomic viral mRNAs in the lungs and greatly reduced induction of cytokine and chemokine mRNAs. A low amount of virus was found in the nasal turbinates of only one of eight rMVA-vaccinated mice on day 2 and none later. Detection of low levels of subgenomic mRNAs in turbinates indicated that replication was aborted in immunized animals.


Asunto(s)
/inmunología , Vectores Genéticos/genética , Vacunas de ADN/inmunología , Virus Vaccinia/genética , /genética , Animales , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Especificidad de Anticuerpos/inmunología , /genética , Modelos Animales de Enfermedad , Expresión Génica , Humanos , Inmunización , Inmunización Pasiva , Inmunoglobulina G/inmunología , Ratones , Ratones Transgénicos , Glicoproteína de la Espiga del Coronavirus/inmunología , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Vacunas de ADN/administración & dosificación , Vacunas de ADN/genética
17.
Cell Rep ; 34(12): 108890, 2021 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-33713594

RESUMEN

Multiple severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines show protective efficacy, which is most likely mediated by neutralizing antibodies recognizing the viral entry protein, spike. Because new SARS-CoV-2 variants are emerging rapidly, as exemplified by the B.1.1.7, B.1.351, and P.1 lineages, it is critical to understand whether antibody responses induced by infection with the original SARS-CoV-2 virus or current vaccines remain effective. In this study, we evaluate neutralization of a series of mutated spike pseudotypes based on divergence from SARS-CoV and then compare neutralization of the B.1.1.7 spike pseudotype and individual mutations. Spike-specific monoclonal antibody neutralization is reduced dramatically; in contrast, polyclonal antibodies from individuals infected in early 2020 remain active against most mutated spike pseudotypes, but potency is reduced in a minority of samples. This work highlights that changes in SARS-CoV-2 spike can alter neutralization sensitivity and underlines the need for effective real-time monitoring of emerging mutations and their effect on vaccine efficacy.


Asunto(s)
Anticuerpos Neutralizantes/inmunología , /genética , Glicoproteína de la Espiga del Coronavirus/genética , Anticuerpos Monoclonales/genética , Anticuerpos Monoclonales/inmunología , Anticuerpos Antivirales/inmunología , Formación de Anticuerpos , /metabolismo , Células HEK293 , Humanos , Pruebas de Neutralización/métodos , Mutación Puntual , Receptores Virales/genética , Receptores Virales/metabolismo , Glicoproteína de la Espiga del Coronavirus/inmunología
18.
Cell ; 184(7): 1804-1820.e16, 2021 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-33691139

RESUMEN

SARS-CoV-2 has caused the global COVID-19 pandemic. Although passively delivered neutralizing antibodies against SARS-CoV-2 show promise in clinical trials, their mechanism of action in vivo is incompletely understood. Here, we define correlates of protection of neutralizing human monoclonal antibodies (mAbs) in SARS-CoV-2-infected animals. Whereas Fc effector functions are dispensable when representative neutralizing mAbs are administered as prophylaxis, they are required for optimal protection as therapy. When given after infection, intact mAbs reduce SARS-CoV-2 burden and lung disease in mice and hamsters better than loss-of-function Fc variant mAbs. Fc engagement of neutralizing antibodies mitigates inflammation and improves respiratory mechanics, and transcriptional profiling suggests these phenotypes are associated with diminished innate immune signaling and preserved tissue repair. Immune cell depletions establish that neutralizing mAbs require monocytes and CD8+ T cells for optimal clinical and virological benefit. Thus, potently neutralizing mAbs utilize Fc effector functions during therapy to mitigate lung infection and disease.


Asunto(s)
Anticuerpos Monoclonales , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Linfocitos T CD8-positivos , Fragmentos Fc de Inmunoglobulinas/inmunología , Animales , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Neutralizantes/inmunología , Anticuerpos Neutralizantes/uso terapéutico , Anticuerpos Antivirales/inmunología , Anticuerpos Antivirales/uso terapéutico , Linfocitos T CD8-positivos/citología , Linfocitos T CD8-positivos/inmunología , Células CHO , /terapia , Chlorocebus aethiops , Cricetulus , Modelos Animales de Enfermedad , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Células Vero , Carga Viral
19.
Emerg Microbes Infect ; 10(1): 638-650, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33704016

RESUMEN

SARS-CoV-2 is the causative agent of COVID-19 and responsible for the current global pandemic. We and others have previously demonstrated that cats are susceptible to SARS-CoV-2 infection and can efficiently transmit the virus to naïve cats. Here, we address whether cats previously exposed to SARS-CoV-2 can be re-infected with SARS-CoV-2. In two independent studies, SARS-CoV-2-infected cats were re-challenged with SARS-CoV-2 at 21 days post primary challenge (DPC) and necropsies performed at 4, 7 and 14 days post-secondary challenge (DP2C). Sentinels were co-mingled with the re-challenged cats at 1 DP2C. Clinical signs were recorded, and nasal, oropharyngeal, and rectal swabs, blood, and serum were collected and tissues examined for histologic lesions. Viral RNA was transiently shed via the nasal, oropharyngeal and rectal cavities of the re-challenged cats. Viral RNA was detected in various tissues of re-challenged cats euthanized at 4 DP2C, mainly in the upper respiratory tract and lymphoid tissues, but less frequently and at lower levels in the lower respiratory tract when compared to primary SARS-CoV-2 challenged cats at 4 DPC. Viral RNA and antigen detected in the respiratory tract of the primary SARS-CoV-2 infected cats at early DPCs were absent in the re-challenged cats. Naïve sentinels co-housed with the re-challenged cats did not shed virus or seroconvert. Together, our results indicate that cats previously infected with SARS-CoV-2 can be experimentally re-infected with SARS-CoV-2; however, the levels of virus shed was insufficient for transmission to co-housed naïve sentinels. We conclude that SARS-CoV-2 infection in cats induces immune responses that provide partial, non-sterilizing immune protection against re-infection.


Asunto(s)
Anticuerpos Antivirales/sangre , Susceptibilidad a Enfermedades/inmunología , Esparcimiento de Virus , Animales , Anticuerpos Neutralizantes/sangre , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Gatos , Línea Celular , Chlorocebus aethiops , ARN Viral/aislamiento & purificación , /virología , Células Vero , Carga Viral
20.
Emerg Microbes Infect ; 10(1): 664-676, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33734013

RESUMEN

Seasonal human coronaviruses (HCoVs) including HCoV-229E, -OC43, -NL63, and -HKU1 widely spread in global human populations. However, the relevance of humoral response against seasonal HCoVs to COVID-19 pathogenesis is elusive. In this study, we profiled the temporal changes of IgG antibody against spike proteins (S-IgG) of SARS-CoV-2 and seasonal HCoVs in 838 plasma samples collected from 344 COVID-19 patients. We tested the antigenic cross-reactivities of S protein between SARS-CoV-2 and seasonal HCoVs and evaluated the correlations between the levels of HCoV-OC43 S-IgG and the disease severity in COVID-19 patients. We found that SARS-CoV-2 S-IgG titres mounted until days 22-28, whereas HCoV-OC43 antibody titres increased until days 15-21 and then plateaued until day 46. However, IgG titres against HCoV-NL63, -229E, and -HKU1 showed no significant increase. A two-way cross-reactivity was identified between SARS-CoV-2 and HCoV-OC43. Neutralizing antibodies against SARS-CoV-2 were not detectable in healthy controls who were positive for HCoV-OC43 S-IgG. HCoV-OC43 S-IgG titres were significantly higher in patients with severe disease than those in mild patients at days 1-21 post symptom onset (PSO). Higher levels of HCoV-OC43 S-IgG were also observed in patients requiring mechanical ventilation. At days 1-10 PSO, HCoV-OC43 S-IgG titres correlated to disease severity in the age group over 60. Our data indicate that there is a correlation between cross-reactive antibody against HCoV-OC43 spike protein and disease severity in COVID-19 patients.


Asunto(s)
Anticuerpos Antivirales/sangre , Coronavirus Humano OC43/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Neutralizantes/sangre , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Reacciones Cruzadas/inmunología , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Adulto Joven
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