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1.
Nat Commun ; 12(1): 5233, 2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-34475387

RESUMO

Measles virus (MeV) is a highly contagious pathogen that enters the human host via the respiratory route. Besides acute pathologies including fever, cough and the characteristic measles rash, the infection of lymphocytes leads to substantial immunosuppression that can exacerbate the outcome of infections with additional pathogens. Despite the availability of effective vaccine prophylaxis, measles outbreaks continue to occur worldwide. We demonstrate that prophylactic and post-exposure therapeutic treatment with an orally bioavailable small-molecule polymerase inhibitor, ERDRP-0519, prevents measles disease in squirrel monkeys (Saimiri sciureus). Treatment initiation at the onset of clinical signs reduced virus shedding, which may support outbreak control. Results show that this clinical candidate has the potential to alleviate clinical measles and augment measles virus eradication.


Assuntos
Inibidores Enzimáticos/uso terapêutico , Sarampo/prevenção & controle , Morfolinas/uso terapêutico , Piperidinas/uso terapêutico , Pirazóis/uso terapêutico , RNA Polimerase Dependente de RNA/antagonistas & inibidores , Animais , Avaliação Pré-Clínica de Medicamentos , Inibidores Enzimáticos/farmacocinética , Tolerância Imunológica/efeitos dos fármacos , Imunidade Humoral/efeitos dos fármacos , Vírus do Sarampo/efeitos dos fármacos , Morfolinas/farmacocinética , Piperidinas/farmacocinética , Pirazóis/farmacocinética , Saimiri , Replicação Viral/efeitos dos fármacos , Eliminação de Partículas Virais/efeitos dos fármacos
2.
Sci Rep ; 11(1): 16543, 2021 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-34400714

RESUMO

Since COVID-19 risk of reinfection is of great concern, the safety and efficacy of the mRNA-based vaccines in previously infected populations should be assessed. We studied 78 individuals previously infected with SARS-CoV-19, who received a single dose of BNT162b2 mRNA COVID-19 vaccine, and 1:2 ratio matched infection-naïve cohort who received two injections. The evaluation procedure included symptom monitoring, and serological tests. Among the post-infected population, the median IgG-S response after the first vaccine dose was 3.35 AU, compared to 2.38 AU after the second vaccine injection in the infection naive group. A strong correlation was demonstrated between IgG-S level before vaccination, and the corresponding responses after a single vaccine dose (r = 0.8, p < 0.001) in the post infected population. Short-term severe symptoms that required medical attention were found in 6.8% among the post-infected individuals, while none were found in the infection naïve population. Our data suggest that a single vaccine dose is sufficient to induce an intense immune response in post-infected population regardless of seropositivity. Although some short-term safety issues were observed compared to the infection naïve population, a single dose regimen can be considered safe in post-infected populations.


Assuntos
Vacinas contra COVID-19/efeitos adversos , COVID-19/prevenção & controle , Reinfecção/prevenção & controle , SARS-CoV-2/imunologia , Vacinação/efeitos adversos , Adulto , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , COVID-19/sangue , COVID-19/diagnóstico , COVID-19/imunologia , Vacinas contra COVID-19/administração & dosagem , Feminino , Humanos , Imunidade Humoral , Imunogenicidade da Vacina , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Masculino , Pessoa de Meia-Idade , Reinfecção/imunologia , Reinfecção/virologia , Estudos Retrospectivos , SARS-CoV-2/isolamento & purificação , Vacinação/métodos
3.
Dtsch Med Wochenschr ; 146(16): 1085-1090, 2021 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-34416777

RESUMO

Since the end of 2019 a new coronavirus, SARS-CoV-2, first identified in Wuhan, China, is spreading around the world partially associated with a high death toll. Besides hygienic measurements to reduce the spread of the virus vaccines have been confected, partially based on the experiences with Ebola virus vaccine, based on recombinant human or chimpanzee adenovirus carrying the spike protein and its ACE2 receptor binding domain (RBD). Further vaccines are constructed by spike protein coding mRNA incorporated in lipid nano vesicles that after entry in human cells produce spike protein. Both vaccine types induce a strong immune response that lasts for months possibly for T-cell immunity a few years. Due to mutations in the coronavirus genome in several parts of the world variants selected, that were partially more pathogenic and partially easier transmissible - variants of concern (VOC). Until now vaccinees are protected against the VOC, even when protection might be reduced compared to the Wuhan wild virus.An open field is still how long the vaccine induced immunity will be sufficient to prevent infection and/or disease; and how long the time period will last until revaccination will be required for life saving protection, whether a third vaccination is needed, and whether revaccination with an adenovirus-based vaccine will be tolerated.


Assuntos
Vacinas contra COVID-19/imunologia , COVID-19/prevenção & controle , Sistema Imunitário/fisiologia , SARS-CoV-2/imunologia , Vacinação/normas , COVID-19/epidemiologia , COVID-19/fisiopatologia , Humanos , Sistema Imunitário/imunologia , Imunidade Celular , Imunidade Humoral , Fatores de Tempo
4.
Signal Transduct Target Ther ; 6(1): 304, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34404759

RESUMO

A comprehensive analysis of the humoral immune response to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is essential in understanding COVID-19 pathogenesis and developing antibody-based diagnostics and therapy. In this work, we performed a longitudinal analysis of antibody responses to SARS-CoV-2 proteins in 104 serum samples from 49 critical COVID-19 patients using a peptide-based SARS-CoV-2 proteome microarray. Our data show that the binding epitopes of IgM and IgG antibodies differ across SARS-CoV-2 proteins and even within the same protein. Moreover, most IgM and IgG epitopes are located within nonstructural proteins (nsps), which are critical in inactivating the host's innate immune response and enabling SARS-CoV-2 replication, transcription, and polyprotein processing. IgM antibodies are associated with a good prognosis and target nsp3 and nsp5 proteases, whereas IgG antibodies are associated with high mortality and target structural proteins (Nucleocapsid, Spike, ORF3a). The epitopes targeted by antibodies in patients with a high mortality rate were further validated using an independent serum cohort (n = 56) and using global correlation mapping analysis with the clinical variables that are associated with COVID-19 severity. Our data provide fundamental insight into humoral immunity during SARS-CoV-2 infection. SARS-CoV-2 immunogenic epitopes identified in this work could also help direct antibody-based COVID-19 treatment and triage patients.


Assuntos
Anticorpos Antivirais/imunologia , COVID-19/imunologia , Imunidade Humoral , SARS-CoV-2/imunologia , Proteínas não Estruturais Virais/imunologia , COVID-19/mortalidade , Estado Terminal , Intervalo Livre de Doença , Epitopos/imunologia , Feminino , Humanos , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Masculino , Análise Serial de Proteínas , Taxa de Sobrevida
6.
Emerg Microbes Infect ; 10(1): 1626-1637, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34365904

RESUMO

Coronaviruses (CoVs) can infect a variety of hosts, including humans, livestock and companion animals, and pose a serious threat to human health and the economy. The current COVID-19 pandemic, which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has killed millions of people. Unfortunately, effective treatments for CoVs infection are still lacking, suggesting the importance of coronavirus vaccines. Our previous work showed that CoV nonstuctural protein 14 (nsp14) functions as (guanine-N7)-methyltransferase (N7-MTase), which is involved in RNA cap formation. Moreover, we found that N7-MTase is well conserved among different CoVs and is a universal target for developing antivirals against CoVs. Here, we show that N7-MTase of CoVs can be an ideal target for designing live attenuated vaccines. Using murine hepatitis virus strain A59 (MHV-A59), a representative and well-studied model of coronaviruses, we constructed N7-MTase-deficient recombinant MHV D330A and Y414A. These two mutants are highly attenuated in mice and exhibit similar replication efficiency to the wild-type (WT) virus in the cell culture. Furthermore, a single dose immunization of D330A or Y414A can induce long-term humoral immune responses and robust CD4+ and CD8+ T cell responses, which can provide full protection against the challenge of a lethal-dose of MHV-A59. Collectively, this study provides an ideal strategy to design live attenuated vaccines for coronavirus by abolishing viral RNA N7-MTase activity. This approach may apply to other RNA viruses that encode their own conservative viral N7-methyltransferase.


Assuntos
Vacinas contra COVID-19/imunologia , COVID-19/prevenção & controle , SARS-CoV-2/imunologia , Vacinas Atenuadas/imunologia , Animais , Vacinas contra COVID-19/administração & dosagem , Citocinas/biossíntese , Humanos , Imunidade Celular , Imunidade Humoral , Imunogenicidade da Vacina , Interferon Tipo I/biossíntese , Masculino , Camundongos , Mutação , Vacinas Atenuadas/administração & dosagem , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/imunologia
7.
Nat Commun ; 12(1): 4984, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34404803

RESUMO

SARS-CoV-2 vaccination has been launched worldwide to build effective population-level immunity to curb the spread of this virus. The effectiveness and duration of protective immunity is a critical factor for public health. Here, we report the kinetics of the SARS-CoV-2 specific immune response in 204 individuals up to 1-year after recovery from COVID-19. RBD-IgG and full-length spike-IgG concentrations and serum neutralizing capacity decreases during the first 6-months, but is maintained stably up to 1-year after hospital discharge. Even individuals who had generated high IgG levels during early convalescent stages had IgG levels that had decreased to a similar level one year later. Notably, the RBD-IgG level positively correlates with serum neutralizing capacity, suggesting the representative role of RBD-IgG in predicting serum protection. Moreover, viral-specific cellular immune protection, including spike and nucleoprotein specific, persisted between 6 months and 12 months. Altogether, our study supports the persistence of viral-specific protective immunity over 1 year.


Assuntos
COVID-19/imunologia , SARS-CoV-2/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , COVID-19/sangue , Humanos , Imunidade Celular/imunologia , Imunidade Humoral/imunologia , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia
8.
J Immunol ; 207(5): 1401-1410, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34380646

RESUMO

PI3Kδ is critical in generating humoral and regulatory immune responses. In this study, we determined the impact of PI3Kδ in immunity to Trypanosoma congolense, an African trypanosome that can manipulate and evade Ab responses critical for protection. Upon infection with T. congolense, PI3KδD910A mice lacking PI3Kδ activity paradoxically show a transient enhancement in early control of parasitemia, associated with impaired production of regulatory IL-10 by B cells in the peritoneum. C57BL/6 wild-type (WT) mice treated with the PI3Kδ inhibitor (PI3Kδi) Idelalisib showed a similar transient decrease in parasitemia associated with reduced IL-10. Strikingly, however, we find that PI3KδD910A mice were ultimately unable to control this infection, resulting in uncontrolled parasitemia and death within 2 wk. Assessment of humoral responses revealed delayed B cell activation, impaired germinal center responses, and compromised Ab responses to differing degrees in PI3KδD910A and PI3Kδi-treated mice. To test the role of Abs, we administered serum from WT mice to PI3KδD910A mice and found that lethality was prevented by postinfection serum. Interestingly, serum from naive WT mice provided partial protection to PI3KδD910A mutants, indicating an additional role for natural Abs. Together our findings suggest that although PI3Kδ drives immune regulatory responses that antagonize early control of parasite growth in the peritoneum, it is also required for generation of Abs that are critical for protection from systemic trypanosome infection. The essential role of PI3Kδ for host survival of African trypanosome infection contrasts with findings for other pathogens such as Leishmania, underlining the critical importance of PI3Kδ-dependent humoral immunity in this disease.


Assuntos
Linfócitos B/imunologia , Classe I de Fosfatidilinositol 3-Quinases/metabolismo , Trypanosoma congolense/fisiologia , Tripanossomíase Africana/imunologia , Animais , Classe I de Fosfatidilinositol 3-Quinases/genética , Imunidade Humoral , Imunomodulação , Interleucina-10/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Parasitemia
9.
Nat Immunol ; 22(9): 1127-1139, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34413521

RESUMO

Follicular helper T (TFH) cells are a specialized subset of CD4+ T cells that essentially support germinal center responses where high-affinity and long-lived humoral immunity is generated. The regulation of TFH cell survival remains unclear. Here we report that TFH cells show intensified lipid peroxidation and altered mitochondrial morphology, resembling the features of ferroptosis, a form of programmed cell death that is driven by iron-dependent accumulation of lipid peroxidation. Glutathione peroxidase 4 (GPX4) is the major lipid peroxidation scavenger and is necessary for TFH cell survival. The deletion of GPX4 in T cells selectively abrogated TFH cells and germinal center responses in immunized mice. Selenium supplementation enhanced GPX4 expression in T cells, increased TFH cell numbers and promoted antibody responses in immunized mice and young adults after influenza vaccination. Our findings reveal the central role of the selenium-GPX4-ferroptosis axis in regulating TFH homeostasis, which can be targeted to enhance TFH cell function in infection and following vaccination.


Assuntos
Ferroptose/fisiologia , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Selênio/farmacologia , Células T Auxiliares Foliculares/fisiologia , Adolescente , Adulto , Animais , Sobrevivência Celular/imunologia , Criança , Feminino , Centro Germinativo/citologia , Centro Germinativo/imunologia , Homeostase/efeitos dos fármacos , Homeostase/genética , Humanos , Imunidade Humoral/imunologia , Vacinas contra Influenza/imunologia , Peroxidação de Lipídeos/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitocôndrias/fisiologia , Ovalbumina , Células T Auxiliares Foliculares/imunologia , Vacinação , Adulto Jovem
10.
Int J Mol Sci ; 22(16)2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34445586

RESUMO

Remote ischemic preconditioning (RIPC) protects hearts from ischemia-reperfusion (I/R) injury in experimental studies; however, clinical RIPC trials were unsatisfactory. This discrepancy could be caused by a loss of cardioprotection due to comorbidities in patients, including diabetes mellitus (DM) and hyperglycemia (HG). RIPC is discussed to confer protective properties by release of different humoral factors activating cardioprotective signaling cascades. Therefore, we investigated whether DM type 1 and/or HG (1) inhibit the release of humoral factors after RIPC and/or (2) block the cardioprotective effect directly at the myocardium. Experiments were performed on male Wistar rats. Animals in part 1 of the study were either healthy normoglycemic (NG), type 1 diabetic (DM1), or hyperglycemic (HG). RIPC was implemented by four cycles of 5 min bilateral hind-limb ischemia/reperfusion. Control (Con) animals were not treated. Blood plasma taken in vivo was further investigated in isolated rat hearts in vitro. Plasma from diseased animals (DM1 or HG) was administered onto healthy (NG) hearts for 10 min before 33 min of global ischemia and 60 min of reperfusion. Part 2 of the study was performed vice versa-plasma taken in vivo, with or without RIPC, from healthy rats was transferred to DM1 and HG hearts in vitro. Infarct size was determined by TTC staining. Part 1: RIPC plasma from NG (NG Con: 49 ± 8% vs. NG RIPC 29 ± 6%; p < 0.05) and DM1 animals (DM1 Con: 47 ± 7% vs. DM1 RIPC: 38 ± 7%; p < 0.05) reduced infarct size. Interestingly, transfer of HG plasma showed comparable infarct sizes independent of prior treatment (HG Con: 34 ± 9% vs. HG RIPC 35 ± 9%; ns). Part 2: No infarct size reduction was detectable when transferring RIPC plasma from healthy rats to DM1 (DM1 Con: 54 ± 13% vs. DM1 RIPC 53 ± 10%; ns) or HG hearts (HG Con: 60 ± 16% vs. HG RIPC 53 ± 14%; ns). These results suggest that: (1) RIPC under NG and DM1 induces the release of humoral factors with cardioprotective impact, (2) HG plasma might own cardioprotective properties, and (3) RIPC does not confer cardioprotection in DM1 and HG myocardium.


Assuntos
Cardiotônicos , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Tipo 1/complicações , Hiperglicemia/complicações , Imunidade Humoral , Precondicionamento Isquêmico Miocárdico/métodos , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Animais , Masculino , Traumatismo por Reperfusão Miocárdica/etiologia , Traumatismo por Reperfusão Miocárdica/patologia , Ratos , Ratos Wistar , Transdução de Sinais
11.
Cell Rep ; 36(8): 109570, 2021 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34390647

RESUMO

The rapid development of mRNA-based vaccines against the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) led to the design of accelerated vaccination schedules that have been extremely effective in naive individuals. While a two-dose immunization regimen with the BNT162b2 vaccine has been demonstrated to provide a 95% efficacy in naive individuals, the effects of the second vaccine dose in individuals who have previously recovered from natural SARS-CoV-2 infection has not been investigated in detail. In this study, we characterize SARS-CoV-2 spike-specific humoral and cellular immunity in naive and previously infected individuals during and after two doses of BNT162b2 vaccination. Our results demonstrate that, while the second dose increases both the humoral and cellular immunity in naive individuals, COVID-19 recovered individuals reach their peak of immunity after the first dose. These results suggests that a second dose, according to the current standard regimen of vaccination, may be not necessary in individuals previously infected with SARS-CoV-2.


Assuntos
COVID-19/prevenção & controle , Linfócitos T/imunologia , Vacinas Sintéticas/administração & dosagem , Anticorpos Antivirais/sangue , Ligante de CD40/metabolismo , COVID-19/imunologia , COVID-19/patologia , COVID-19/virologia , Vacinas contra COVID-19/administração & dosagem , Vacinas contra COVID-19/química , Vacinas contra COVID-19/imunologia , Humanos , Imunidade Celular , Imunidade Humoral , Imunoglobulina G/sangue , Interferon gama/metabolismo , Interleucina-2/metabolismo , Peptídeos/imunologia , SARS-CoV-2/isolamento & purificação , SARS-CoV-2/metabolismo , Glicoproteína da Espícula de Coronavírus/imunologia , Linfócitos T/citologia , Linfócitos T/metabolismo , Vacinação , Vacinas Sintéticas/imunologia
12.
EBioMedicine ; 70: 103539, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34391087

RESUMO

BACKGROUND: In recent months numerous health care professional acquired COVID-19 at the workplace resulting in significant shortages in medical and nursing staff. We investigated how prior COVID-19 affects SARS-CoV-2 vaccination and how such knowledge could facilitate frugal vaccination strategies. METHODS: In a cohort of 41 healthcare professionals with (n=14) and without (n=27) previous SARS-CoV-2 infection, we assessed the immune status before, during and after vaccination with BNT162b2. The humoral immune response was assessed by receptor binding domain ELISA and different SARS-CoV-2 neutralisation assays using wildtype and pseudo-typed viruses. T cell immunity against SARS-CoV-2 surface and nucleocapsid peptides were studied using interferon-γ release assays and intracellular flow cytometry. Vaccine-related side effects were captured. FINDINGS: Prior COVID-19 resulted in improved vaccine responses both in the B and T cell compartment. In vaccine recipients with prior COVID-19, the first vaccine dose induced high antibody concentrations comparable to seronegative vaccine recipients after two injections. This translated into more efficient neutralisation of virus particles, even more pronounced than expected from the RBD ELISA results. Furthermore, T cell responses were stronger in convalescents and particularly strong against the SARS-CoV-2 nucleocapsid protein. INTERPRETATION: Herein, we corroborate recent findings suggesting that in convalescents a single vaccine dose is sufficient to boost adequate in vitro neutralisation of SARS-CoV-2 and therefore may be sufficient to induce adequate protection against severe COVID-19. New spike mutated virus variants render the highly conserved nucleocapsid protein - eliciting strong SARS-CoV-2 specific T cell immunity - an interesting additional vaccine target. FUNDING: Christian Doppler Research Association, Johannes Kepler University Linz.


Assuntos
Linfócitos B/imunologia , Vacinas contra COVID-19/imunologia , COVID-19/imunologia , SARS-CoV-2/imunologia , Linfócitos T/imunologia , Adulto , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/virologia , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Pessoal de Saúde , Humanos , Imunidade Humoral/imunologia , Masculino , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinação/métodos
13.
EBioMedicine ; 70: 103524, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34391096

RESUMO

BACKGROUND: Patients with chronic renal insufficiency on maintenance haemodialysis face an increased risk of COVID-19 induced mortality and impaired vaccine responses. To date, only a few studies have addressed SARS-CoV-2 vaccine elicited immunity in this immunocompromised population. METHODS: We assessed immunogenicity of the mRNA vaccine BNT162b2 in at-risk dialysis patients and characterised systemic cellular and humoral immune responses in serum and saliva using interferon γ release assay and multiplex-based cytokine and immunoglobulin measurements. We further compared binding capacity and neutralization efficacy of vaccination-induced immunoglobulins against emerging SARS-CoV-2 variants Alpha, Beta, Epsilon and Cluster 5 by ACE2-RBD competition assay. FINDINGS: Patients on maintenance haemodialysis exhibit detectable but variable cellular and humoral immune responses against SARS-CoV-2 and variants of concern after a two-dose regimen of BNT162b2. Although vaccination-induced immunoglobulins were detectable in saliva and plasma, both anti-SARS-CoV-2 IgG and neutralization efficacy was reduced compared to a vaccinated non-dialysed control population. Similarly, T-cell mediated interferon γ release after stimulation with SARS-CoV-2 spike peptides was significantly diminished. INTERPRETATION: Quantifiable humoral and cellular immune responses after BNT162b2 vaccination in individuals on maintenance haemodialysis are encouraging, but urge for longitudinal follow-up to assess longevity of immunity. Diminished virus neutralization and interferon γ responses in the face of emerging variants of concern may favour this at-risk population for re-vaccination using modified vaccines at the earliest opportunity. FUNDING: Initiative and Networking Fund of the Helmholtz Association of German Research Centres, EU Horizon 2020 research and innovation program, State Ministry of Baden-Württemberg for Economic Affairs, Labour and Tourism.


Assuntos
Vacinas contra COVID-19/imunologia , COVID-19/imunologia , Imunidade Celular/imunologia , Imunidade Humoral/imunologia , Imunogenicidade da Vacina/imunologia , SARS-CoV-2/imunologia , Vacinas Sintéticas/imunologia , Idoso , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Feminino , Humanos , Imunoglobulina G/imunologia , Masculino , Pessoa de Meia-Idade , Diálise Renal/métodos , Glicoproteína da Espícula de Coronavírus/imunologia , Linfócitos T/imunologia , Vacinação/métodos
14.
Lancet Respir Med ; 9(9): 999-1009, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34224675

RESUMO

BACKGROUND: Concurrent with the Pfizer-BioNTech BNT162b2 COVID-19 vaccine roll-out in Israel initiated on Dec 19, 2020, we assessed the early antibody responses and antibody kinetics after each vaccine dose in health-care workers of different ages and sexes, and with different comorbidities. METHODS: We did a prospective, single-centre, longitudinal cohort study at the Sheba Medical Centre (Tel-Hashomer, Israel). Eligible participants were health-care workers at the centre who had a negative anti-SARS-CoV-2 IgG assay before receiving the first dose of the intramuscular vaccine, and at least one serological antibody test after the first dose of the vaccine. Health-care workers with a positive SARS-CoV-2 PCR test before vaccination, a positive anti-SARS-CoV-2 IgG serology test before vaccination, or infection with COVID-19 after vaccination were excluded from the study. Participants were followed up weekly for 5 weeks after the first vaccine dose; a second dose was given at week 3. Serum samples were obtained at baseline and at each weekly follow-up, and antibodies were tested at 1-2 weeks after the first vaccine dose, at week 3 with the administration of the second vaccine dose, and at weeks 4-5 (ie, 1-2 weeks after the second vaccine dose). Participants with comorbidities were approached to participate in an enriched comorbidities subgroup, and at least two neutralising assays were done during the 5 weeks of follow-up in those individuals. IgG assays were done for the entire study population, whereas IgM, IgA, and neutralising antibody assays were done only in the enriched comorbidities subgroup. Concentrations of IgG greater than 0·62 sample-to-cutoff (s/co) ratio and of IgA greater than 1·1 s/co, and titres of neutralising antibodies greater than 10 were considered positive. Scatter plot and correlation analyses, logistic and linear regression analyses, and linear mixed models were used to investigate the longitudinal antibody responses. FINDINGS: Between Dec 19, 2020, and Jan 30, 2021, we obtained 4026 serum samples from 2607 eligible, vaccinated participants. 342 individuals were included in the enriched comorbidities subgroup. The first vaccine dose elicited positive IgG and neutralising antibody responses at week 3 in 707 (88·0%) of 803 individuals, and 264 (71·0%) of 372 individuals, respectively, which were rapidly increased at week 4 (ie, 1 week after the second vaccine dose) in 1011 (98·4%) of 1027 and 357 (96·5%) of 370 individuals, respectively. Over 4 weeks of follow-up after vaccination, a high correlation (r=0·92) was detected between IgG against the receptor-binding domain and neutralising antibody titres. First-dose induced IgG response was significantly lower in individuals aged 66 years and older (ratio of means 0·25, 95% CI 0·19-0·31) and immunosuppressed individuals (0·21, 0·14-0·31) compared with individuals aged 18·00-45·99 years and individuals with no immunosuppression, respectively. This disparity was partly abrogated following the second dose. Overall, endpoint regression analysis showed that lower antibody concentrations were consistently associated with male sex (ratio of means 0·84, 95% CI 0·80-0·89), older age (ie, ≥66 years; 0·64, 0·58-0·71), immunosuppression (0·44, 0·33-0·58), and other specific comorbidities: diabetes (0·88, 0·79-0·98), hypertension (0·90, 0·82-0·98), heart disease (0·86, 0·75-1·00), and autoimmune diseases (0·82, 0·73-0·92). INTERPRETATION: BNT162b2 vaccine induces a robust and rapid antibody response. The significant correlation between receptor-binding domain IgG antibodies and neutralisation titres suggests that IgG antibodies might serve as a correlate of neutralisation. The second vaccine dose is particularly important for older and immunosuppressed individuals, highlighting the need for timely second vaccinations and potentially a revaluation of the long gap between doses in some countries. Antibody responses were reduced in susceptible populations and therefore they might be more prone to breakthrough infections. FUNDING: Sheba Medical Center, Israel Ministry of Health.


Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Vacinas contra COVID-19/imunologia , COVID-19/prevenção & controle , Pessoal de Saúde/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/isolamento & purificação , COVID-19/epidemiologia , COVID-19/imunologia , COVID-19/virologia , Vacinas contra COVID-19/administração & dosagem , Feminino , Seguimentos , Humanos , Imunidade Humoral , Imunogenicidade da Vacina , Israel/epidemiologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Pandemias/prevenção & controle , Estudos Prospectivos , SARS-CoV-2/imunologia , Vacinação/métodos , Vacinação/estatística & dados numéricos , Adulto Jovem
15.
EBioMedicine ; 70: 103495, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34304047

RESUMO

BACKGROUND: Children are underrepresented in the COVID-19 pandemic and often experience milder disease than adolescents and adults. Reduced severity is possibly due to recent and more frequent seasonal human coronaviruses (HCoV) infections. We assessed the seroprevalence of SARS-CoV-2 and seasonal HCoV specific antibodies in a large cohort in north-eastern France. METHODS: In this cross-sectional seroprevalence study, serum samples were collected from children and adults requiring hospital admission for non-COVID-19 between February and August 2020. Antibody responses to SARS-CoV-2 and seasonal HCoV (229E, HKU1, NL63, OC43) were assessed using a bead-based multiplex assay, Luciferase-Linked ImmunoSorbent Assay, and a pseudotype neutralisation assay. FINDINGS: In 2,408 individuals, seroprevalence of SARS-CoV-2-specific antibodies was 7-8% with three different immunoassays. Antibody levels to seasonal HCoV increased substantially up to the age of 10. Antibody responses in SARS-CoV-2 seropositive individuals were lowest in adults 18-30 years. In SARS-CoV-2 seronegative individuals, we observed cross-reactivity between antibodies to the four HCoV and SARS-CoV-2 Spike. In contrast to other antibodies to SARS-CoV-2, specific antibodies to sub-unit 2 of Spike (S2) in seronegative samples were highest in children. Upon infection with SARS-CoV-2, antibody levels to Spike of betacoronavirus OC43 increased across the whole age spectrum. No SARS-CoV-2 seropositive individuals with low levels of antibodies to seasonal HCoV were observed. INTERPRETATION: Our findings underline significant cross-reactivity between antibodies to SARS-CoV-2 and seasonal HCoV, but provide no significant evidence for cross-protective immunity to SARS-CoV-2 infection due to a recent seasonal HCoV infection. In particular, across all age groups we did not observe SARS-CoV-2 infected individuals with low levels of antibodies to seasonal HCoV. FUNDING: This work was supported by the « URGENCE COVID-19 ¼ fundraising campaign of Institut Pasteur, by the French Government's Investissement d'Avenir program, Laboratoire d'Excellence Integrative Biology of Emerging Infectious Diseases (Grant No. ANR-10-LABX-62-IBEID), and by the REACTing (Research & Action Emerging Infectious Diseases), and by the RECOVER project funded by the European Union's Horizon 2020 research and innovation programme under grant agreement No. 101003589, and by a grant from LabEx IBEID (ANR-10-LABX-62-IBEID).


Assuntos
COVID-19/imunologia , Imunidade Humoral/imunologia , SARS-CoV-2/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antivirais/imunologia , Criança , Pré-Escolar , Ensaios Clínicos como Assunto , Reações Cruzadas/imunologia , Estudos Transversais , Feminino , França , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Pandemias/prevenção & controle , Estações do Ano , Estudos Soroepidemiológicos , Glicoproteína da Espícula de Coronavírus/imunologia , Adulto Jovem
16.
J Immunol ; 207(4): 1033-1043, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34321231

RESUMO

A single dose of the replication-competent, live-attenuated yellow fever virus (YFV) 17D vaccine provides lifelong immunity against human YFV infection. The magnitude, kinetics, and specificity of B cell responses to YFV 17D are relatively less understood than T cell responses. In this clinical study, we focused on early immune events critical for the development of humoral immunity to YFV 17D vaccination in 24 study subjects. More specifically, we studied the dynamics of several immune cell populations over time and the development of neutralizing Abs. At 7 d following vaccination, YFV RNA in serum as well as several antiviral proteins were detected as a sign of YFV 17D replication. Activation of Th1-polarized circulating T follicular helper cells followed germinal center activity, the latter assessed by the surrogate marker CXCL13 in serum. This coincided with a plasmablast expansion peaking at day 14 before returning to baseline levels at day 28. FluoroSpot-based analysis confirmed that plasmablasts were specific to the YFV-E protein. The frequencies of plasmablasts correlated with the magnitude of neutralizing Ab titers measured at day 90, suggesting that this transient B cell subset could be used as an early marker of induction of protective immunity. Additionally, YFV-specific memory B cells were readily detectable at 28 and 90 d following vaccination, and all study subjects tested developed protective neutralizing Ab titers. Taken together, these studies provide insights into key immune events leading to human B cell immunity following vaccination with the YFV 17D vaccine.


Assuntos
Anticorpos Neutralizantes/imunologia , Células T Auxiliares Foliculares/imunologia , Vacina contra Febre Amarela/imunologia , Febre Amarela/imunologia , Vírus da Febre Amarela/imunologia , Adolescente , Adulto , Anticorpos Antivirais/imunologia , Antígenos Virais/imunologia , Linfócitos B/imunologia , Citocinas/imunologia , Feminino , Humanos , Imunidade Humoral/imunologia , Cinética , Masculino , Pessoa de Meia-Idade , Vacinação/métodos , Vacinas Atenuadas/imunologia , Adulto Jovem
17.
Nat Commun ; 12(1): 4144, 2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34230476

RESUMO

To investigate the duration of humoral immune response in convalescent coronavirus disease 2019 (COVID-19) patients, we conduct a 12-month longitudinal study through collecting a total of 1,782 plasma samples from 869 convalescent plasma donors in Wuhan, China and test specific antibody responses. The results show that positive rate of IgG antibody against receptor-binding domain of spike protein (RBD-IgG) to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the COVID-19 convalescent plasma donors exceeded 70% for 12 months post diagnosis. The level of RBD-IgG decreases with time, with the titer stabilizing at 64.3% of the initial level by the 9th month. Moreover, male plasma donors produce more RBD-IgG than female, and age of the patients positively correlates with the RBD-IgG titer. A strong positive correlation between RBD-IgG and neutralizing antibody titers is also identified. These results facilitate our understanding of SARS-CoV-2-induced immune memory to promote vaccine and therapy development.


Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Imunoglobulina G/sangue , Receptores Virais/imunologia , SARS-CoV-2/imunologia , Adulto , Animais , Doadores de Sangue , COVID-19/terapia , Linhagem Celular , China , Chlorocebus aethiops , Convalescença , Feminino , Humanos , Imunidade Humoral/imunologia , Imunização Passiva , Memória Imunológica/imunologia , Estudos Longitudinais , Masculino , Fatores Sexuais , Glicoproteína da Espícula de Coronavírus/imunologia , Células Vero
18.
Signal Transduct Target Ther ; 6(1): 256, 2021 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-34234102

RESUMO

We collected blood from coronavirus disease 2019 (COVID-19) convalescent individuals and investigated SARS-CoV-2-specific humoral and cellular immunity in these discharged patients. Follow-up analysis in a cohort of 171 patients at 4-11 months after the onset revealed high levels of IgG antibodies. A total of 78.1% (164/210) of the specimens tested positive for neutralizing antibody (NAb). SARS-CoV-2 antigen peptide pools-stimulated-IL-2 and -IFN-γ response can distinguish COVID-19 convalescent individuals from healthy donors. Interestingly, NAb survival was significantly affected by the antigen peptide pools-stimulated-IL-2 response, -IL-8 response, and -IFN-γ response. The antigen peptide pools-activated CD8+ T cell counts were correlated with NAb. The antigen peptide pools-activated natural killer (NK) cell counts in convalescent individuals were correlated with NAb and disease severity. Our data suggested that the development of NAb is associated with the activation of T cells and NK cells. Our work provides a basis for further analysis of the protective immunity to SARS-CoV-2 and for understanding the pathogenesis of COVID-19. It also has implications for the development of an effective vaccine for SARS-CoV-2 infection.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Convalescença , Citocinas/imunologia , Feminino , Humanos , Imunidade Celular , Imunidade Humoral , Imunoglobulina G/imunologia , Subpopulações de Linfócitos/imunologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
19.
Front Immunol ; 12: 708820, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34249017

RESUMO

During the COVID19 pandemic, a range of vaccines displayed high efficacy in preventing disease, severe outcomes of infection, and mortality. However, the immunological correlates of protection, the duration of immune response, the transmission risk over time from vaccinated individuals are currently under active investigation. In this brief report, we describe the case of a vaccinated Healthcare Professional infected with a variant of Sars-CoV-2, who has been extensively investigated in order to draw a complete trajectory of infection. The patient has been monitored for the whole length of infection, assessing the temporal viral load decay, the quantification of viral RNA and subgenomic mRNA, antibodies (anti Sars-CoV-2, IgA, IgG, IgM) and cell-mediated (cytokine, B- and T-cell profiles) responses. Overall, this brief report highlights the efficacy of vaccine in preventing COVID19 disease, accelerating the recovery from infection, reducing the transmission risk, although the use of precautionary measures against Sars-CoV-2 spreading still remain critical.


Assuntos
Linfócitos B/imunologia , Vacinas contra COVID-19/imunologia , COVID-19/imunologia , Pessoal de Saúde , SARS-CoV-2/fisiologia , Linfócitos T/imunologia , Adulto , Doenças Assintomáticas , COVID-19/diagnóstico , COVID-19/prevenção & controle , COVID-19/transmissão , Transmissão de Doença Infecciosa , Feminino , Humanos , Imunidade Humoral , Itália , RNA Viral/análise , Risco , Vacinação , Carga Viral
20.
Front Immunol ; 12: 684014, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34194438

RESUMO

T cells play a fundamental role in the early control and clearance of many viral infections of the respiratory system. In SARS-CoV-2-infected individuals, lymphopenia with drastically reduced CD4+ and CD8+ T cells correlates with Coronavirus disease 2019 (COVID-19)-associated disease severity and mortality. In this study, we characterized cellular and humoral immune responses induced in patients with mild, severe and critical COVID-19. Peripheral blood mononuclear cells of 37 patients with mild, severe and critical COVID-19 and 10 healthy individuals were analyzed by IFNγ ELISpot and multi-color flow cytometry upon stimulation with peptide pools covering complete immunodominant SARS-CoV-2 matrix, nucleocapsid and spike proteins. In addition SARS-CoV-2 antibody levels, neutralization abilities and anaphylatoxin levels were evaluated by various commercially available ELISA platforms. Our data clearly demonstrates a significantly stronger induction of SARS-CoV-2 specific CD8+ T lymphocytes and higher IFNγ production in patients with mild compared to patients with severe or critical COVID-19. In all patients SARS-CoV-2-specific antibodies with similar neutralizing activity were detected, but highest titers of total IgGs were observed in critical patients. Finally, elevated anaphylatoxin C3a and C5a levels were identified in severe and critical COVID-19 patients probably caused by aberrant immune complex formation due to elevated antibody titers in these patients. Crucially, we provide a full picture of cellular and humoral immune responses of COVID-19 patients and prove that robust polyfunctional CD8+ T cell responses concomitant with low anaphylatoxin levels correlate with mild infections. In addition, our data indicates that high SARS-CoV-2 antibody titers are associated with severe disease progression.


Assuntos
Anafilatoxinas/metabolismo , Linfócitos T CD8-Positivos/imunologia , COVID-19/imunologia , SARS-CoV-2/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , COVID-19/fisiopatologia , Progressão da Doença , ELISPOT , Feminino , Citometria de Fluxo , Humanos , Imunidade Humoral , Interferon gama/sangue , Masculino , Pessoa de Meia-Idade , Gravidade do Paciente
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