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1.
PLoS One ; 17(1): e0262162, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34982806

RESUMO

Analysis of convalescent plasma derived from individuals has shown that IgG3 has the most important role in binding to SARS-CoV-2 antigens; however, this has not yet been confirmed in large studies, and the link between binding and neutralization has not been confirmed. By analyzing plasma pools consisting of 247-567 individual convalescent donors, we demonstrated the binding of IgG3 and IgM to Spike-1 protein and the receptor-binding domain correlates strongly with viral neutralization in vitro. Furthermore, despite accounting for only approximately 12% of total immunoglobulin mass, collectively IgG3 and IgM account for approximately 80% of the total neutralization. This may have important implications for the development of potent therapies for COVID-19, as it indicates that hyperimmune globulins or convalescent plasma donations with high IgG3 concentrations may be a highly efficacious therapy.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/sangue , COVID-19/imunologia , Convalescença , Imunoglobulina G/imunologia , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Chlorocebus aethiops , Ensaio de Imunoadsorção Enzimática , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , SARS-CoV-2/fisiologia , Células Vero
2.
J Med Virol ; 94(1): 388-392, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34415572

RESUMO

In the current COVID-19 pandemic, a better understanding of the relationship between merely binding and functionally neutralizing antibodies is necessary to characterize protective antiviral immunity following infection or vaccination. This study analyzes the level of correlation between the novel quantitative EUROIMMUN Anti-SARS-CoV-2 QuantiVac ELISA (IgG) and a microneutralization assay. A panel of 123 plasma samples from a COVID-19 outbreak study population, preselected by semiquantitative anti-SARS-CoV-2 IgG testing, was used to assess the relationship between the novel quantitative ELISA (IgG) and a microneutralization assay. Binding IgG targeting the S1 antigen was detected in 106 (86.2%) samples using the QuantiVac ELISA, while 89 (72.4%) samples showed neutralizing antibody activity. Spearman's correlation analysis demonstrated a strong positive relationship between anti-S1 IgG levels and neutralizing antibody titers (rs = 0.819, p < 0.0001). High and low anti-S1 IgG levels were associated with a positive predictive value of 72.0% for high-titer neutralizing antibodies and a negative predictive value of 90.8% for low-titer neutralizing antibodies, respectively. These results substantiate the implementation of the QuantiVac ELISA to assess protective immunity following infection or vaccination.


Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Ensaio de Imunoadsorção Enzimática/métodos , Imunoglobulina G/sangue , SARS-CoV-2/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/imunologia , COVID-19/patologia , Teste Sorológico para COVID-19/métodos , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes de Neutralização/métodos , Sensibilidade e Especificidade , Glicoproteína da Espícula de Coronavírus/imunologia , Adulto Jovem
3.
J Med Virol ; 94(1): 173-177, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34427924

RESUMO

In this study, it was aimed to determine the antibody responses after the two doses of inactivated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccinations in people who were above 65 years old and to evaluate the factors affecting this response. A total of 235 participants aged 65 years and older were included. Blood samples were taken and data about age, gender, comorbid diseases, and presence of side effects after vaccination were noted. Anti-SARS-CoV-2 QuantiVac ELISA (IgG) test kit (catalogue number: EI-2606-9601-10-G, Euroimmun) was used. The mean age was 70.38 ± 4.76. Approximately 120 of 235 participants had at least one comorbid disease. The mean levels of anti-SARS-CoV-2 IgG antibody after 4 weeks from the first and second doses of vaccine were 37.70 ± 57.08 IU/ml, and 194.61 ± 174.88 IU/ml, respectively. Additionally, 134 of 235 participants (57.02%) had under 25.6 IU/ml antibody level (negative) after 4 weeks from the first vaccine dose while this rate was 11.48% (n = 27) after 4 weeks from the second vaccine dose. The 19 (70.4%) participants who had under had 25.6 IU/ml antibody level after 4 weeks from the first dose of vaccine had at least one comorbid disease including diabetes mellitus, and 8 (29.6%) participants had no comorbid disease (F = 2.352, p = 0.006). Lower rates of antibody response were detected in participants aged 65 years and older and those with comorbidities both in our study and similar studies in the current literature. Further studies should evaluate whether the low antibody titers are really associated with age and comorbidities or not. Finally, prospective studies are needed to determine how long the immunity provided by SARS-CoV-2 vaccines will continue.


Assuntos
Anticorpos Antivirais/sangue , Vacinas contra COVID-19/imunologia , Imunogenicidade da Vacina , SARS-CoV-2/imunologia , Idoso , Idoso de 80 Anos ou mais , Vacinas contra COVID-19/administração & dosagem , Comorbidade , Feminino , Humanos , Imunoglobulina G/sangue , Masculino , Vacinas de Produtos Inativados/imunologia
4.
J Med Virol ; 94(1): 186-196, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34427932

RESUMO

In classical viral infections, the avidity of immunoglobulin G (IgG) is low during acute infection and high a few months later. As recently reported, SARS-CoV-2 infections are not following this scheme, but they are rather characterized by incomplete avidity maturation. This study was performed to clarify whether infection with seasonal coronaviruses also leads to incomplete avidity maturation. The avidity of IgG toward the nucleoprotein (NP) of the seasonal coronaviruses 229E, NL63, OC43, HKU1 and of SARS-CoV-2 was determined in the sera from 88 healthy, SARS-CoV-2-negative subjects and in the sera from 70 COVID-19 outpatients, using the recomLine SARS-CoV-2 assay with recombinant antigens. In the sera from SARS-CoV-2-negative subjects, incomplete avidity maturation (persistent low and intermediate avidity indices) was the lowest for infections with the alpha-coronaviruses 229E (33.3%) and NL63 (61.3%), and the highest for the beta-coronaviruses OC43 (77.5%) and HKU1 (71.4%). In the sera from COVID-19 patients, the degree of incomplete avidity maturation of IgG toward NP of 223E, OC43, and HKU1 was not significantly different from that found in SARS-CoV-2-negative subjects, but a significant increase in avidity was observed for IgG toward NP of NL63. Though there was no cross-reaction between SARS-CoV-2 and seasonal coronaviruses, higher concentrations of IgG directed toward seasonal coronaviruses seemed to indirectly increase avidity maturation of IgG directed toward SARS-CoV-2. Our data show that incomplete IgG avidity maturation represents a characteristic consequence of coronavirus infections. This raises problems for the serological differentiation between acute and past infections and may be important for the biology of coronaviruses.


Assuntos
Alphacoronavirus/imunologia , Afinidade de Anticorpos , Betacoronavirus/imunologia , COVID-19/imunologia , Infecções por Coronavirus/imunologia , Imunoglobulina G/imunologia , SARS-CoV-2/imunologia , Adolescente , Adulto , Idoso , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Coronavirus Humano NL63/imunologia , Proteínas do Nucleocapsídeo de Coronavírus/imunologia , Coronavirus Humano OC43/imunologia , Reações Cruzadas , Feminino , Humanos , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Fosfoproteínas/imunologia , Estações do Ano , Adulto Jovem
5.
J Med Virol ; 94(1): 178-185, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34428312

RESUMO

Many aspects of the humoral immune response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), such as its role in protection after natural infection, are still unclear. We evaluated IgA and IgG response to spike subunits 1 and 2 (S1 and S2) and Nucleocapsid proteins of SARS-COV-2 in serum samples of 109 volunteers with viral RNA detected or seroconversion with different clinical evolution (asymptomatic, mild, moderate, and severe coronavirus disease 2019), using the ViraChip® Test Kit. We observed that the quantification of antibodies to all antigens had a positive correlation to disease severity, which was strongly associated with the presence of comorbidities. Seroreversion was not uncommon even during the short (median of 77 days) observation, occurring in 15% of mild-asymptomatic cases at a median of 55 days for IgG and 46 days for IgA. The time to reach the maximal antibody response did not differ significantly among recovered and deceased volunteers. Our study illustrated the dynamic of anti-S1, anti-N, and anti-S2 IgA and IgG antibodies, and suggests that high production of IgG and IgA does not guarantee protection to disease severity and that functional responses that have been studied by other groups, such as antibody avidity, need further attention.


Assuntos
Anticorpos Antivirais/sangue , COVID-19/imunologia , Proteínas do Nucleocapsídeo de Coronavírus/imunologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Fosfoproteínas/imunologia , Soroconversão , Adulto Jovem
7.
J Neuroimmunol ; 362: 577788, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-34922128

RESUMO

OBJECTIVES: To report clinical outcome, development of humoral and T-cell mediated immunity in convalescent COVID-19 people with multiple sclerosis (pwMS) treated with ofatumumab in the ALITHIOS study from a single center. METHODS: Testing for SARS-Cov2 IgG antibodies was performed on two occasions with at least three months apart between the two testing. During the second antibody testing, interferon-γ ELISpot was used to assess cellular immunity. RESULTS: All four subjects had mild COVID-19 infection without any sequelae. In all subjects except subject 2, COVID-19 was confirmed with PCR. Subjects 1, 2 and 4 had normal levels of IgM and IgG without measurable counts of CD19 cells prior to COVID-19. Subject 3 administered the last dose of ofatumumab 24 days prior to COVID-19 symptoms, but had a gap of 28 weeks of ofatumumab application beforehand due to low IgM levels. Subject 4 received COVID-19 vaccinations before second testing, so second testing and T-cell immunity testing were not performed. Subjects who were CD19 depleted did not had measurable levels of SARS-Cov2 IgG antibodies. Subject 3 had first and second SARS-COV2 titer of 118 U/ml and > 250 U/ml, respectively. All three pwMS showed T cell immunity against SARS-CoV-2. Quotient of basal spots divided by interferon-γ secreting spot forming units were 4, 8 and 14.7 SI in subjects 1, 2 and 3, respectively (>3 considered reactive). CONCLUSION: While no antibody response was observed in pwMS who were CD19+ lymphocyte depleted, T cell immunity against SARS-CoV-2 was observed in all three pwMS treated with ofatumumab.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , COVID-19/imunologia , Esclerose Múltipla/complicações , Esclerose Múltipla/imunologia , Adulto , Anticorpos Antivirais/sangue , COVID-19/complicações , Ensaios Clínicos Fase III como Assunto , Feminino , Humanos , Imunidade Celular/imunologia , Imunidade Humoral/imunologia , Masculino
8.
Mol Immunol ; 141: 287-296, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34915268

RESUMO

As the second wave of COVID-19 launched, various variants of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) have emerged with a dramatic global spread amongst millions of people causing unprecedented case fatalities and economic shut-downs. That initiated a necessity for developing specific diagnostics and therapeutics along with vaccines to control such a pandemic. This endeavor describes generation of murine derived recombinant single-chain fragment variable (scFv) as a monoclonal antibody (MAb) platform targeting the receptor binding domain (RBD) of Spike protein of SARS-CoV-2. A specific synthesized RBD coding sequence was cloned and expressed in Baculovirus expression system. The recombinant RBD (rRBD) was ascertained to be at the proper encoding size of ∼ 600bp and expressed protein of the molecular weight of ∼ 21KDa. Purified rRBD was proved genuinely antigenic and immunogenic, exhibiting specific reactivity to anti-SARS-CoV-2 antibody in an indirect enzyme-linked immunosorbent assay (ELISA), and inducing strong seroconversion in immunized mice. The scFv phage display library against rRBD was successfully constructed, revealing ∼ 90 % recombination frequency, and great enriching factor reaching 88 % and 25 % in polyclonal Ab-based and MAb-based ELISAs, respectively. Typically, three unique scFvs were generated, selected, purified and molecularly identified. That was manifested by their: accurate structure, close relation to the mouse immunoglobulin (Ig) superfamily, right anchored six complementarily-determining regions (CDRs) as three within variable heavy (vH) and variable light (vL) regions each, and proper configuration of the three-dimensional (3D) structure. Besides, their expression downstream in a non-suppressive amber codon of E. coli strain SS32 created a distinct protein band at an apparent molecular weight of ∼ 27KDa. Moreover, the purified scFvs showed authentic immunoreactivity and specificity to both rRBD and SARS-CoV-2 in western blot and ELISA. Accordingly, these developed scFvs platform might be a functional candidate for research, inexpensive diagnostics and therapeutics, mitigating spread of COVID-19.


Assuntos
Enzima de Conversão de Angiotensina 2/metabolismo , Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/imunologia , Teste Sorológico para COVID-19 , COVID-19/diagnóstico , Técnicas de Visualização da Superfície Celular , Epitopos/imunologia , Receptores Virais/metabolismo , SARS-CoV-2/imunologia , Anticorpos de Cadeia Única/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/biossíntese , Anticorpos Antivirais/sangue , Especificidade de Anticorpos , Baculoviridae , COVID-19/prevenção & controle , Escherichia coli , Feminino , Vetores Genéticos , Camundongos , Camundongos Endogâmicos BALB C , Modelos Moleculares , Biblioteca de Peptídeos , Conformação Proteica , Domínios Proteicos , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/imunologia , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Anticorpos de Cadeia Única/biossíntese , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo
9.
Emerg Microbes Infect ; 11(1): 250-259, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34951566

RESUMO

Testing and vaccination have been major components of the strategy for combating the ongoing COVID-19 pandemic. In this study, we have developed a quantitative anti-SARS-CoV-2 spike (S1) IgG antibody assay using a fingerstick dried blood sample. We evaluated the feasibility of using this high-throughput and quantitative anti-SARS-CoV-2 spike (S1) IgG antibody testing assay in vaccinated individuals. Fingerstick blood samples were collected and analyzed from 137 volunteers before and after receiving the Moderna or Pfizer mRNA vaccine. Anti-SARS-CoV-2 S1 IgG antibody could not be detected within the first 7 days after receiving the first vaccine dose, however, the assay reliably detected antibodies from day 14 onwards. In addition, no anti-SARS-CoV-2 nucleocapsid (N) protein IgG antibody was detected in any of the vaccinated or healthy participants, indicating that the anti-SARS-CoV-2 S1 IgG assay is specific for the mRNA vaccine-induced antibodies. The S1 IgG levels detected in fingerstick samples correlated with the levels found in venous blood plasma samples and with the efficacy of venous blood plasma samples in the plaque reduction neutralization test (PRNT). The assay displayed a limit of quantification (LOQ) of 0.59 µg/mL and was found to be linear in the range of 0.51-1000 µg/mL. Finally, its clinical performance displayed a Positive Percent Agreement (PPA) of 100% (95% CI: 0.89-1.00) and a Negative Percent Agreement (NPA) of 100% (95% CI: 0.93-1.00). In summary, the assay described here represents a sensitive, precise, accurate, and simple method for the quantitative detection and monitoring of post-vaccination anti-SARS-CoV-2 spike IgG responses.


Assuntos
Teste Sorológico para COVID-19/métodos , Vacinas contra COVID-19/imunologia , COVID-19/imunologia , Ensaios de Triagem em Larga Escala/métodos , Imunoensaio/métodos , SARS-CoV-2/imunologia , Manejo de Espécimes/métodos , Anticorpos Antivirais/sangue , Feminino , Humanos , Imunoglobulina G/sangue , Masculino , Glicoproteína da Espícula de Coronavírus , Vacinação
10.
J Autoimmun ; 126: 102782, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34920343

RESUMO

The development of various autoimmune diseases has been reported after COVID-19 infections or vaccinations. However, no method for assessing the relationships between vaccines and the development of autoimmune diseases has been established. Aplastic anemia (AA) is an immune-mediated bone marrow failure syndrome. We report a case of severe AA that arose after the administration of a COVID-19 vaccine (the Pfizer-BioNTech mRNA vaccine), which was treated with allogeneic hematopoietic stem cell transplantation (HSCT). In this patient, antibodies against the SARS-CoV-2 spike protein were detected both before and after the HSCT. After the patient's hematopoietic stem cells were replaced through HSCT, his AA improved despite the presence of anti-SARS-CoV-2 antibodies. In this case, antibodies derived from the COVID-19 vaccine may not have been directly involved in the development of AA. This case suggests that the measurement of vaccine antibody titers before and after allogeneic HSCT may provide clues to the pathogenesis of vaccine-related autoimmune diseases. Although causality was not proven in this case, further evaluations are warranted to assess the associations between vaccines and AA.


Assuntos
Anemia Aplástica/induzido quimicamente , COVID-19/prevenção & controle , Transplante de Células-Tronco Hematopoéticas , Anticorpos Antivirais/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Glicoproteína da Espícula de Coronavírus/imunologia
11.
Life Sci Alliance ; 5(2)2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34848436

RESUMO

The clinical outcome of SARS-CoV-2 infections, which can range from asymptomatic to lethal, is crucially shaped by the concentration of antiviral antibodies and by their affinity to their targets. However, the affinity of polyclonal antibody responses in plasma is difficult to measure. Here we used microfluidic antibody affinity profiling (MAAP) to determine the aggregate affinities and concentrations of anti-SARS-CoV-2 antibodies in plasma samples of 42 seropositive individuals, 19 of which were healthy donors, 20 displayed mild symptoms, and 3 were critically ill. We found that dissociation constants, K d, of anti-receptor-binding domain antibodies spanned 2.5 orders of magnitude from sub-nanomolar to 43 nM. Using MAAP we found that antibodies of seropositive individuals induced the dissociation of pre-formed spike-ACE2 receptor complexes, which indicates that MAAP can be adapted as a complementary receptor competition assay. By comparison with cytopathic effect-based neutralisation assays, we show that MAAP can reliably predict the cellular neutralisation ability of sera, which may be an important consideration when selecting the most effective samples for therapeutic plasmapheresis and tracking the success of vaccinations.


Assuntos
Anticorpos Antivirais/sangue , COVID-19/imunologia , Microfluídica/métodos , SARS-CoV-2/imunologia , Adulto , Idoso , Enzima de Conversão de Angiotensina 2/sangue , Enzima de Conversão de Angiotensina 2/imunologia , Anticorpos Antivirais/imunologia , Afinidade de Anticorpos , Linfócitos B/imunologia , Linfócitos B/virologia , COVID-19/sangue , COVID-19/etiologia , Reações Cruzadas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Glicoproteína da Espícula de Coronavírus/sangue , Glicoproteína da Espícula de Coronavírus/imunologia , Ressonância de Plasmônio de Superfície
12.
Am J Public Health ; 112(1): 38-42, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34936397

RESUMO

We conducted a community seroprevalence survey in Arizona, from September 12 to October 1, 2020, to determine the presence of antibodies to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We used the seroprevalence estimate to predict SARS-CoV-2 infections in the jurisdiction by applying the adjusted seroprevalence to the county's population. The estimated community seroprevalence of SARS-CoV-2 infections was 4.3 times greater (95% confidence interval = 2.2, 7.5) than the number of reported cases. Field surveys with representative sampling provide data that may help fill in gaps in traditional public health reporting. (Am J Public Health. 2022;112(1):38-42. https://doi.org/10.2105/AJPH.2021.306568).


Assuntos
Anticorpos Antivirais/sangue , Teste Sorológico para COVID-19 , COVID-19/diagnóstico , COVID-19/epidemiologia , Adolescente , Adulto , Idoso , Arizona/epidemiologia , Criança , Características da Família , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prática de Saúde Pública , SARS-CoV-2 , Estudos Soroepidemiológicos
13.
Vet Microbiol ; 264: 109306, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34923247

RESUMO

Currently, highly pathogenic avian influenza (HPAI) H7N9 viruses still pose a potential pandemic threat. Influenza virus-like particle (VLP) is one of the most promising vaccine strategies to complement traditional egg-dependent vaccines. Here, we generated a H7N9 VLP vaccine candidate by baculovirus expression system and evaluated its efficacy in chickens and mice. The H7N9 VLP was produced through co-infection of Sf9 insect cells with three recombinant baculoviruses expressing individual HA, NA and M1 gene of the HPAI H7N9 virus A/chicken/Guangdong/GD15/2016. Intramuscular immunization of the H7N9 VLP elicited robust antibody immune responses and conferred complete clinical protection against lethal H7N9 virus challenge both in chickens and mice. Meanwhile, H7N9 VLP significantly restrained virus shedding and dramatically alleviated pulmonary lesions caused by H7N9 virus infection in birds and mice. Interestingly, chicken antibodies induced by the H7N9 VLP also had a good cross-reactivity with H7N9 field strains isolated in different years. In addition, vaccination with the H7N9 VLP elicited high T cell immunity in mouse lung, evidenced by significantly upregulated expression of IL-2, IL-4 and IFN-γ. Furthermore, the H7N9 VLP significantly decreased the expression of some key inflammatory cytokines, such as IL6, RANTES and TNF-α in mouse lung, which may partially account for its contribution to alleviate lung pathology. Therefore, our study describes the good efficacy of the HA + NA + M1-containing H7N9 VLP both in chicken and mice models, highlighting the potential of VLP-based vaccine as a critical alternative of traditional egg-based vaccine for control of H7N9 influenza virus in both humans and poultry.


Assuntos
Baculoviridae , Subtipo H7N9 do Vírus da Influenza A , Vacinas contra Influenza , Influenza Aviária , Infecções por Orthomyxoviridae , Vacinas de Partículas Semelhantes a Vírus , Animais , Anticorpos Antivirais/sangue , Baculoviridae/imunologia , Galinhas , Subtipo H7N9 do Vírus da Influenza A/imunologia , Vacinas contra Influenza/imunologia , Influenza Aviária/prevenção & controle , Camundongos , Infecções por Orthomyxoviridae/prevenção & controle , Vacinas de Partículas Semelhantes a Vírus/imunologia
14.
J Med Virol ; 94(1): 380-383, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34403142

RESUMO

The durability of infection-induced severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) immunity has crucial implications for reinfection and vaccine effectiveness. However, the relationship between coronavirus disease 2019 (COVID-19) severity and long-term anti-SARS-CoV-2 immunoglobulin G (IgG) antibody level is poorly understood. Here, we measured the longevity of SARS-CoV-2-specific IgG antibodies in survivors who had recovered from COVID-19 1 year previously. In a cohort of 473 survivors with varying disease severity (asymptomatic, mild, moderate, or severe), we observed a positive correlation between virus-specific IgG antibody titers and COVID-19 severity. In particular, the highest virus-specific IgG antibody titers were observed in patients with severe COVID-19. By contrast, 74.4% of recovered asymptomatic carriers had negative anti-SARS-CoV-2 IgG test results, while many others had very low virus-specific IgG antibody titers. Our results demonstrate that SARS-CoV-2-specific IgG persistence and titer depend on COVID-19 severity.


Assuntos
Anticorpos Antivirais/sangue , COVID-19/patologia , Imunoglobulina G/sangue , SARS-CoV-2/imunologia , Índice de Gravidade de Doença , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Infecções Assintomáticas , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Adulto Jovem
18.
J Med Virol ; 94(1): 399-403, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34460119

RESUMO

Vaccination generates a neutralizing immune response against SARS-CoV-2. The genomic surveillance is showing the emergence of variants with mutations in spike, the main target of neutralizing antibodies. To understand the impact of these variants, we report the neutralization potency against alpha, gamma, and D614G SARS-CoV-2 variants in 44 individuals that received two doses of CoronaVac vaccine, an inactivated SARS-CoV-2 vaccine. Plasma samples collected at 60 days after the second dose of CoronaVac were analyzed by the reduction of cytopathic effect in Vero E6 cells with the three infectious variants of SARS-CoV-2. Plasma showed lower neutralization with alpha (geometric mean titer [GMT] = 18.5) and gamma (GMT = 10.0) variants than with D614G (GMT = 75.1) variant. Efficient neutralization against the alpha and gamma variants was not detected in 31.8% and 59.1% of plasma, respectively. These findings suggest the alpha and gamma variants could escape from neutralization by antibodies elicited by vaccination. Robust genomic and biological surveillance of viral variants could help to develop effective strategies for the control of SARS-CoV-2.


Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Vacinas contra COVID-19/imunologia , COVID-19/prevenção & controle , SARS-CoV-2/imunologia , Adulto , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/imunologia , Linhagem Celular , Chlorocebus aethiops , Feminino , Humanos , Evasão da Resposta Imune/imunologia , Masculino , Pessoa de Meia-Idade , Testes de Neutralização , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinação , Vacinas de Produtos Inativados/imunologia , Células Vero , Adulto Jovem
19.
J Med Virol ; 94(1): 279-286, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34468990

RESUMO

Vaccines have been seen as the most important solution for ending the coronavirus disease 2019 (COVID-19) pandemic. The aim of this study is to evaluate the antibody levels after inactivated virus vaccination. We included 148 healthcare workers (74 with prior COVID-19 infection and 74 with not). They received two doses of inactivated virus vaccine (CoronaVac). Serum samples were prospectively collected three times (Days 0, 28, 56). We measured SARS-CoV-2 IgGsp antibodies quantitatively and neutralizing antibodies. After the first dose, antibody responses did not develop in 64.8% of the participants without prior COVID-19 infection. All participants had developed antibody responses after the second dose. We observed that IgGsp antibody titers elicited by a single vaccine dose in participants with prior COVID-19 infection were higher than after two doses of vaccine in participants without prior infection (geometric mean titer: 898 and 607 AU/ml). IgGsp antibodies, participants with prior COVID-19 infection had higher antibody levels as geometric mean titers at all time points (p < 0.001). We also found a positive correlation between IgGsp antibody titers and neutralizing capacity (rs = 0.697, p < 0.001). Although people without prior COVID-19 infection should complete their vaccination protocol, the adequacy of a single dose of vaccine is still in question for individuals with prior COVID-19. New methods are needed to measure the duration of protection of vaccines and their effectiveness against variants as the world is vaccinated. We believe quantitative IgGsp values may reflect the neutralization capacity of some vaccines.


Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Vacinas contra COVID-19/imunologia , Imunogenicidade da Vacina/imunologia , SARS-CoV-2/imunologia , Vacinas de Produtos Inativados/imunologia , Adulto , COVID-19/imunologia , COVID-19/prevenção & controle , Comorbidade , Feminino , Pessoal de Saúde/estatística & dados numéricos , Humanos , Imunização Secundária , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Vacinação , Adulto Jovem
20.
J Med Virol ; 94(1): 287-290, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34487373

RESUMO

In the 10th month of the pandemic, coronavirus disease 2019 (COVID-19) vaccination was given first to healthcare workers in Turkey after receiving emergency use approval from the Ministry of Health. This study, which was performed at the COVID-19 reference center in Ankara (the capital of Turkey) aimed to evaluate the seroconversion rate of the CoronaVac vaccine. The anti-spike immunoglobulin G response to the two-dose vaccination was retrospectively examined in healthcare workers who had no previous history of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. The postvaccine seroconversion rate was investigated by measuring the antibody levels of healthcare workers who had received CoronaVac. Vaccination was administered as 600 SU in 28-day intervals. The healthcare workers' anti-SARS-CoV-2 immunoglobulin G levels were used to determine the seroconversion rate 2 months after the second dose of the vaccine. Of the healthcare workers, 22.9% (n = 155) were seronegative. The younger the age of the participant, the higher the level of anti-SARS-CoV-2 immunoglobulin G. Furthermore, anti-SARS-CoV-2 immunoglobulin G levels were much higher in women than men.


Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Vacinas contra COVID-19/imunologia , COVID-19/prevenção & controle , Imunização Secundária/métodos , SARS-CoV-2/imunologia , Adulto , Idoso , COVID-19/imunologia , Proteínas do Nucleocapsídeo de Coronavírus/imunologia , Feminino , Pessoal de Saúde/estatística & dados numéricos , Humanos , Esquemas de Imunização , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Fosfoproteínas/imunologia , Estudos Retrospectivos , Soroconversão/fisiologia , Turquia , Vacinas de Produtos Inativados/imunologia , Vacinas Sintéticas/imunologia , Adulto Jovem
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