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1.
Nat Commun ; 13(1): 1614, 2022 03 28.
Article in English | MEDLINE | ID: covidwho-1764178

ABSTRACT

SARS-CoV-2 vaccines are crucial in controlling COVID-19, but knowledge of which factors determine waning immunity is limited. We examined antibody levels and T-cell gamma-interferon release after two doses of BNT162b2 vaccine or a combination of ChAdOx1-nCoV19 and BNT162b2 vaccines for up to 230 days after the first dose. Generalized mixed models with and without natural cubic splines were used to determine immunity over time. Antibody responses were influenced by natural infection, sex, and age. IgA only became significant in naturally infected. A one-year IgG projection suggested an initial two-phase response in those given the second dose delayed (ChAdOx1/BNT162b2) followed by a more rapid decrease of antibody levels. T-cell responses correlated significantly with IgG antibody responses. Our results indicate that IgG levels will drop at different rates depending on prior infection, age, sex, T-cell response, and the interval between vaccine injections. Only natural infection mounted a significant and lasting IgA response.


Subject(s)
COVID-19 , Viral Vaccines , Antibodies, Viral , COVID-19/prevention & control , COVID-19 Vaccines , Humans , SARS-CoV-2 , Vaccination , Vaccines, Inactivated
2.
Frontiers in immunology ; 13, 2022.
Article in English | EuropePMC | ID: covidwho-1733176

ABSTRACT

Background Previous studies have indicated inferior responses to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) vaccination in solid organ transplant (SOT) recipients. We examined the development of anti-receptor-binding domain (RBD) immunoglobulin G (IgG) after two doses of BNT162b2b in SOT recipients 6 months after vaccination and compared to that of immunocompetent controls. Methods We measured anti-RBD IgG after two doses of BNT162b2 in 200 SOT recipients and 200 matched healthy controls up to 6 months after first vaccination. Anti-RBD IgG concentration and neutralizing capacity of antibodies were measured at first and second doses of BNT162b2 and 2 and 6 months after the first dose. T-cell responses were measured 6 months after the first dose. Results In SOT recipients, geometric mean concentration (GMC) of anti-RBD IgG increased from first to second dose (1.14 AU/ml, 95% CI 1.08–1.24 to 11.97 AU/ml, 95% CI 7.73–18.77) and from second dose to 2 months (249.29 AU/ml, 95% CI 153.70–385.19). Six months after the first vaccine, anti-RBD IgG declined (55.85 AU/ml, 95% CI 36.95–83.33). At all time points, anti-RBD IgG was lower in SOT recipients than that in controls. Fewer SOT recipients than controls had a cellular response (13.1% vs. 59.4%, p < 0.001). Risk factors associated with humoral non-response included age [relative risk (RR) 1.23 per 10-year increase, 95% CI 1.11–1.35, p < 0.001], being within 1 year from transplantation (RR 1.55, 95% CI 1.30–1.85, p < 0.001), treatment with mycophenolate (RR 1.54, 95% CI 1.09–2.18, p = 0.015), treatment with corticosteroids (RR 1.45, 95% CI 1.10–1.90, p = 0.009), kidney transplantation (RR 1.70, 95% CI 1.25–2.30, p = 0.001), lung transplantation (RR 1.63, 95% CI 1.16–2.29, p = 0.005), and de novo non-skin cancer comorbidity (RR 1.52, 95% CI, 1.26–1.82, p < 0.001). Conclusion Immune responses to BNT162b2 are inferior in SOT recipients compared to healthy controls, and studies aiming to determine the clinical impact of inferior vaccine responses are warranted.

3.
J Innate Immun ; : 1-9, 2022 Jan 21.
Article in English | MEDLINE | ID: covidwho-1642959

ABSTRACT

The course of COVID-19 is unpredictable, ranging from asymptomatic to respiratory failure and death. Prognostic biomarkers are urgently needed. We hypothesized that long pentraxin PTX3 could be a valuable plasma biomarker due to its essential role in inflammatory processes. In a prospective hospitalized COVID-19 derivation cohort (n = 126) during the spring of 2020, we measured PTX3 within 4 days of admission. The predictive value of mechanical ventilation (MV) and 30-day mortality compared with clinical parameters and other markers of inflammation were assessed by logistic regression analysis and expressed as odds ratio (OR) with 95% confidence interval (CI). Analyses were repeated in a prospective validation cohort (n = 112) of hospitalized patients with COVID-19 treated with remdesivir and dexamethasone. Thirty-day mortality in the derivation cohort was 26.2%. In patients who died, the median PTX3 concentration upon admission was 19.5 ng/mL (IQR: 12.5-33.3) versus 6.6 ng/mL (IQR 2.9-12.3) (p < 0.0001) for survivors. After adjustment for covariates, the odds of 30-day mortality increased two-fold for each doubling of PTX3 (OR 2.03 [95% CI: 1.23-3.34], p = 0.006), which was also observed in the validation cohort (OR 1.70 [95% CI: 1.09-2.67], p = 0.02). Similarly, PTX3 levels were associated with MV. After adjustment for covariates, OR of MV was 2.34 (95% CI: 1.33-4.12, p = 0.003) in the derivation cohort and 1.64 (95% CI: 1.03-2.62, p = 0.04) in the validation cohort. PTX3 appears to be a useful clinical biomarker to predict 30-day respiratory failure and mortality risk in COVID-19 patients treated with and without remdesivir and dexamethasone.

4.
J Intern Med ; 291(4): 513-518, 2022 04.
Article in English | MEDLINE | ID: covidwho-1541774

ABSTRACT

BACKGROUND: People with HIV (PWH) are at increased risk of severe COVID-19. We aimed to determine humoral responses in PWH and controls who received two doses of BNT162b2. METHODS: In 269 PWH and 538 age-matched controls, we measured IgG and neutralizing antibodies specific for the receptor-binding domain of SARS-CoV-2 at baseline, 3 weeks and 2 months after the first dose of BNT162b2. RESULTS: IgG antibodies increased from baseline to 3 weeks and from 3 weeks to 2 months in both groups, but the concentrations of IgG antibodies were lower in PWH than that in controls at 3 weeks and 2 months (p = 0.025 and <0.001), respectively. The IgG titres in PWH with a humoral response at 2 months were 77.9% (95% confidence interval [62.5%-97.0%], age- and sex-adjusted p = 0.027) of controls. CONCLUSIONS: Reduced IgG antibody response to vaccination with BNT162b2 was found in PWH, and thus increased awareness of breakthrough infections in PWH is needed.


Subject(s)
COVID-19 , HIV Infections , COVID-19/prevention & control , HIV Infections/complications , Humans , Infant, Newborn , SARS-CoV-2 , Vaccination
5.
Elife ; 102021 11 25.
Article in English | MEDLINE | ID: covidwho-1534520

ABSTRACT

The alpha/B.1.1.7 SARS-CoV-2 lineage emerged in autumn 2020 in the United Kingdom and transmitted rapidly until winter 2021 when it was responsible for most new COVID-19 cases in many European countries. The incidence domination was likely due to a fitness advantage that could be driven by the receptor-binding domain (RBD) residue change (N501Y), which also emerged independently in other variants of concern such as the beta/B.1.351 and gamma/P.1 strains. Here, we present a functional characterization of the alpha/B.1.1.7 variant and show an eightfold affinity increase towards human angiotensin-converting enzyme-2 (ACE-2). In accordance with this, transgenic hACE2 mice showed a faster disease progression and severity after infection with a low dose of B.1.1.7, compared to an early 2020 SARS-CoV-2 isolate. When challenged with sera from convalescent individuals or anti-RBD monoclonal antibodies, the N501Y variant showed a minor, but significant elevated evasion potential of ACE-2/RBD antibody neutralization. The data suggest that the single asparagine to tyrosine substitution remarkable rise in affinity may be responsible for the higher transmission rate and severity of the B.1.1.7 variant.


Subject(s)
Angiotensin-Converting Enzyme 2/metabolism , COVID-19/virology , SARS-CoV-2/metabolism , Spike Glycoprotein, Coronavirus/metabolism , Angiotensin-Converting Enzyme 2/immunology , Animals , Antibodies, Monoclonal/metabolism , Antibodies, Neutralizing/metabolism , Antibodies, Viral/metabolism , COVID-19/genetics , COVID-19/metabolism , Disease Progression , Female , Humans , Male , Mice , Mutation, Missense , Protein Binding , SARS-CoV-2/genetics , SARS-CoV-2/immunology , Severity of Illness Index , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/immunology , United Kingdom
6.
Front Immunol ; 12: 767981, 2021.
Article in English | MEDLINE | ID: covidwho-1528824

ABSTRACT

The ongoing pandemic of coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to constitute a serious public health threat worldwide. Protective antibody-mediated viral neutralization in response to SARS-CoV-2 infection has been firmly characterized. Where the effects of the antibody response are generally considered to be beneficial, an important biological question regarding potential negative outcomes of a SARS-CoV-2 antibody response has yet to be answered. We determined the distribution of IgG subclasses and complement activation levels in plasma from convalescent individuals using in-house developed ELISAs. The IgG response towards SARS-CoV-2 receptor-binding domain (RBD) after natural infection appeared to be mainly driven by IgG1 and IgG3 subclasses, which are the main ligands for C1q mediated classical complement pathway activation. The deposition of the complement components C4b, C3bc, and TCC as a consequence of SARS-CoV-2 specific antibodies were depending primarily on the SARS-CoV-2 RBD and significantly correlated with both IgG levels and disease severity, indicating that individuals with high levels of IgG and/or severe disease, might have a more prominent complement activation during viral infection. Finally, freshly isolated monocytes and a monocyte cell line (THP-1) were used to address the cellular mediated inflammatory response as a consequence of Fc-gamma receptor engagement by SARS-CoV-2 specific antibodies. Monocytic Fc gamma receptor charging resulted in a significant rise in the secretion of the pro-inflammatory cytokine TNF-α. Our results indicate that SARS-CoV-2 antibodies might drive significant inflammatory responses through the classical complement pathway and via cellular immune-complex activation that could have negative consequences during COVID-19 disease. We found that increased classical complement activation was highly associated to COVID-19 disease severity. The combination of antibody-mediated complement activation and subsequent cellular priming could constitute a significant risk of exacerbating COVID-19 severity.


Subject(s)
Antibodies, Viral/blood , COVID-19/immunology , Complement System Proteins/immunology , Immunoglobulin G/blood , SARS-CoV-2/immunology , COVID-19/blood , Complement Activation , Cytokines/immunology , Humans , Inflammation/immunology , Receptors, IgG/immunology , THP-1 Cells
7.
Front Immunol ; 12: 757197, 2021.
Article in English | MEDLINE | ID: covidwho-1485060

ABSTRACT

The recent identification and rise to dominance of the P.1 and B.1.351 SARS-CoV-2 variants have brought international concern because they may confer fitness advantages. The same three positions in the receptor-binding domain (RBD) are affected in both variants, but where the 417 substitution differs, the E484K/N501Y have co-evolved by convergent evolution. Here we characterize the functional and immune evasive consequences of the P.1 and B.1.351 RBD mutations. E484K and N501Y result in gain-of-function with two different outcomes: The N501Y confers a ten-fold affinity increase towards ACE-2, but a modest antibody evasion potential of plasma from convalescent or vaccinated individuals, whereas the E484K displays a significant antibody evasion capacity without a major impact on affinity. On the other hand, the two different 417 substitutions severely impair the RBD/ACE-2 affinity, but in the combined P.1 and B.1.351 RBD variants, this effect is partly counterbalanced by the effect of the E484K and N501Y. Our results suggest that the combination of these three mutations is a two-step forward and one step back in terms of viral fitness.


Subject(s)
Angiotensin-Converting Enzyme 2/immunology , Antibodies, Viral/immunology , COVID-19 Vaccines , Mutation, Missense , SARS-CoV-2 , Spike Glycoprotein, Coronavirus , Vaccination , Adult , Amino Acid Substitution , COVID-19 Vaccines/administration & dosage , COVID-19 Vaccines/immunology , Female , Humans , Male , Protein Domains , SARS-CoV-2/genetics , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/immunology
8.
Front Immunol ; 12: 758154, 2021.
Article in English | MEDLINE | ID: covidwho-1477831

ABSTRACT

The coronavirus disease 2019 (COVID-19) pandemic has severely impacted daily life all over the world. Any measures to slow down the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and to decrease disease severity are highly requested. Recent studies have reported inverse correlations between plasma levels of vitamin D and susceptibility to SARS-CoV-2 infection and COVID-19 severity. Therefore, it has been proposed to supplement the general population with vitamin D to reduce the impact of COVID-19. However, by studying the course of COVID-19 and the immune response against SARS-CoV-2 in a family with a mutated, non-functional vitamin D receptor, we here demonstrate that vitamin D signaling was dispensable for mounting an efficient adaptive immune response against SARS-CoV-2 in this family. Although these observations might not directly be transferred to the general population, they question a central role of vitamin D in the generation of adaptive immunity against SARS-CoV-2.


Subject(s)
B-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , Familial Hypophosphatemic Rickets/genetics , Receptors, Calcitriol/genetics , SARS-CoV-2/immunology , Adaptive Immunity/genetics , Adaptive Immunity/immunology , COVID-19/immunology , Familial Hypophosphatemic Rickets/immunology , Female , Humans , Immunologic Memory/immunology , Lymphocyte Count , Vitamin D/blood , Vitamin D/therapeutic use
10.
J Immunol ; 207(3): 878-887, 2021 08 01.
Article in English | MEDLINE | ID: covidwho-1323338

ABSTRACT

Tools to monitor SARS-CoV-2 transmission and immune responses are needed. We present a neutralization ELISA to determine the levels of Ab-mediated virus neutralization and a preclinical model of focused immunization strategy. The ELISA is strongly correlated with the elaborate plaque reduction neutralization test (ρ = 0.9231, p < 0.0001). The neutralization potency of convalescent sera strongly correlates to IgG titers against SARS-CoV-2 receptor-binding domain (RBD) and spike (ρ = 0.8291 and 0.8297, respectively; p < 0.0001) and to a lesser extent with the IgG titers against protein N (ρ = 0.6471, p < 0.0001). The preclinical vaccine NMRI mice models using RBD and full-length spike Ag as immunogens show a profound Ab neutralization capacity (IC50 = 1.9 × 104 to 2.6 × 104 and 3.9 × 103 to 5.2 × 103, respectively). Using a panel of novel high-affinity murine mAbs, we also show that a majority of the RBD-raised mAbs have inhibitory properties, whereas only a few of the spike-raised mAbs do. The ELISA-based viral neutralization test offers a time- and cost-effective alternative to the plaque reduction neutralization test. The immunization results indicate that vaccine strategies focused only on the RBD region may have advantages compared with the full spike.


Subject(s)
Antibodies, Neutralizing/blood , Coronavirus Nucleocapsid Proteins/immunology , Enzyme-Linked Immunosorbent Assay/methods , Neutralization Tests/methods , Receptors, Virus/immunology , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Angiotensin-Converting Enzyme 2/immunology , Animals , Antibodies, Monoclonal/immunology , Antibodies, Neutralizing/immunology , Antibodies, Viral/blood , Antibodies, Viral/immunology , Antigens, Viral/immunology , COVID-19/immunology , COVID-19/therapy , COVID-19 Vaccines/immunology , Humans , Immunization , Immunization, Passive , Immunoglobulin A/blood , Immunoglobulin A/immunology , Immunoglobulin G/blood , Immunoglobulin G/immunology , Immunoglobulin M/blood , Immunoglobulin M/immunology , Mice , Protein Domains/immunology
12.
J Immunol ; 206(1): 109-117, 2021 01 01.
Article in English | MEDLINE | ID: covidwho-1067832

ABSTRACT

Globally, the COVID-19 pandemic has had extreme consequences for the healthcare system and has led to calls for diagnostic tools to monitor and understand the transmission, pathogenesis, and epidemiology, as well as to evaluate future vaccination strategies. In this study, we have developed novel, to our knowledge, flexible ELISA-based assays for specific detection of human SARS-CoV-2 Abs against the receptor-binding domain, including an Ag sandwich ELISA relevant for large population screening and three isotype-specific assays for in-depth diagnostics. Their performance was evaluated in a cohort of 350 convalescent participants with previous COVID-19 infection, ranging from asymptomatic to critical cases. We mapped the Ab responses to different areas on protein N and S and showed that the IgM, A, and G Ab responses against receptor-binding domain are significantly correlated to the disease severity. These assays and the data generated from them are highly relevant for diagnostics and prognostics and contribute to the understanding of long-term COVID-19 immunity.


Subject(s)
Antibodies, Viral/immunology , COVID-19/diagnosis , COVID-19/immunology , Convalescence , SARS-CoV-2/immunology , Adolescent , Adult , Aged , Aged, 80 and over , Antibodies, Neutralizing/immunology , Enzyme-Linked Immunosorbent Assay , Female , Humans , Immunoglobulin A/immunology , Immunoglobulin G/immunology , Immunoglobulin M/immunology , Male , Middle Aged , Reverse Transcriptase Polymerase Chain Reaction , SARS-CoV-2/genetics , Severity of Illness Index , Young Adult
13.
J Immunol ; 206(1): 109-117, 2021 01 01.
Article in English | MEDLINE | ID: covidwho-934538

ABSTRACT

Globally, the COVID-19 pandemic has had extreme consequences for the healthcare system and has led to calls for diagnostic tools to monitor and understand the transmission, pathogenesis, and epidemiology, as well as to evaluate future vaccination strategies. In this study, we have developed novel, to our knowledge, flexible ELISA-based assays for specific detection of human SARS-CoV-2 Abs against the receptor-binding domain, including an Ag sandwich ELISA relevant for large population screening and three isotype-specific assays for in-depth diagnostics. Their performance was evaluated in a cohort of 350 convalescent participants with previous COVID-19 infection, ranging from asymptomatic to critical cases. We mapped the Ab responses to different areas on protein N and S and showed that the IgM, A, and G Ab responses against receptor-binding domain are significantly correlated to the disease severity. These assays and the data generated from them are highly relevant for diagnostics and prognostics and contribute to the understanding of long-term COVID-19 immunity.


Subject(s)
Antibodies, Viral/immunology , COVID-19/diagnosis , COVID-19/immunology , Convalescence , SARS-CoV-2/immunology , Adolescent , Adult , Aged , Aged, 80 and over , Antibodies, Neutralizing/immunology , Enzyme-Linked Immunosorbent Assay , Female , Humans , Immunoglobulin A/immunology , Immunoglobulin G/immunology , Immunoglobulin M/immunology , Male , Middle Aged , Reverse Transcriptase Polymerase Chain Reaction , SARS-CoV-2/genetics , Severity of Illness Index , Young Adult
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