ABSTRACT
Determining SARS-CoV-2 immunity is critical to assess COVID-19 risk and the need for prevention and mitigation strategies. We measured SARS-CoV-2 Spike/Nucleocapsid seroprevalence and serum neutralizing activity against Wu01, BA.4/5 and BQ.1.1 in 1,411 individuals who received medical treatment in five emergency departments in North Rhine-Westphalia, Germany. We detected Spike-IgG in 95.6%, Nucleocapsid-IgG in 24.0% and neutralization against Wu01, BA.4/5 and BQ.1.1 in 94.4%, 85.0%, and 73.8% of participants, respectively. Neutralization against BA.4/5 and BQ.1.1 was reduced 5.6- and 23.4-fold compared to Wu01. Accuracy of S-IgG detection for determination of neutralizing activity against BQ.1.1 was reduced substantially. Furthermore, we explored previous vaccinations and infections as most important correlates of improved BQ.1.1 neutralization using multivariable and Bayesian network analyses. Given an adherence to COVID-19 vaccination recommendations of only 67.7% of all participants, we highlight the need for improvement of vaccine-uptake to reduce the COVID-19 risk in upcoming infection-waves with immune evasive variants.
Subject(s)
Severe Acute Respiratory Syndrome , COVID-19ABSTRACT
Throughout the SARS-CoV-2 pandemic, Germany lacked an adaptive population panel for epidemic diseases and a modelling platform to rapidly incorporate panel estimates. We evaluated how a cross-sectional analysis of 9922 participants of the MuSPAD study in June/July 2022 combined with a newly developed modelling platform could bridge the gap and analyzed antibody levels, neutralizing serum activity and interferon-gamma release response of serum samples. We categorized the population into four groups with differing protection against severe course of disease (validated by neutralizing serum activity), and found that 30% were in the group with highest protection, and 85% in either the highest categories or second highest group regarding protection level. Estimated hospitalizations due to SARS-CoV-2 were predicted to be between 30 to 300% of the peak in 02/2021 dependent on assumed variant characteristics. We showed the feasibility of a rapid epidemic panel able to evaluate complex endpoints for SARS-CoV-2 and inform scenario modelling.
Subject(s)
Encephalitis, ArbovirusABSTRACT
Despite intensive research since the emergence of SARS-CoV-2, it has remained unclear precisely which components of the early immune response protect against the development of severe COVID-19. To address this issue, we performed a comprehensive immunogenetic and virologic analysis of nasopharyngeal and peripheral blood samples obtained during the acute phase of infection with SARS-CoV-2. We found that soluble and transcriptional markers of systemic inflammation peaked during the first week after symptom onset and correlated directly with the upper airways viral loads (UA-VLs), whereas the contemporaneous frequencies of circulating viral nucleocapsid (NC)-specific CD4+ and CD8+ T cells correlated inversely with various inflammatory markers and UA-VLs. In addition, we observed high frequencies of activated CD4+ and CD8+ T cells in acutely infected nasopharyngeal tissue, many of which expressed genes encoding various effector molecules, such as cytotoxic proteins and IFN-γ. The presence of functionally active T cells in the infected epithelium was further linked with common patterns of gene expression among virus-susceptible target cells and better local control of SARS-CoV-2. Collectively, these results identified an immune correlate of protection against SARS-CoV-2, which could inform the development of more effective vaccines to combat the acute and chronic illnesses attributable to COVID-19.
Subject(s)
Inflammation , COVID-19ABSTRACT
The recently emerged BA.2.75 Omicron sublineage of SARS-CoV-2 identified in numerous countries is rapidly increasing in prevalence in regions of India. Compared with BA.2, the spike protein of BA.2.75 differs in nine amino acid residues. To determine the impact of the spike mutations on polyclonal and monoclonal antibody activity, we investigated the neutralization sensitivity of BA.2.75 in comparison with B.1, BA.2, BA.2.12.1, and BA.4/5. Analysis of post-boost samples from 30 vaccinated individuals revealed significantly lower serum neutralizing activity against BA.2.75 than against BA.2. However, BA.2.75 was more sensitive to serum neutralization than the widely circulating BA.4/5 sublineages. Moreover, evaluation of 17 clinical-stage monoclonal antibodies demonstrated individual differences in Omicron sublineage activity. Notably, some authorized antibodies with low activity against other Omicron sublineages demonstrated high BA.2.75 neutralizing potency. Our results indicate a less pronounced degree of antibody evasion of BA.2.75 compared with BA.4/5 and suggest that factors beyond immune evasion may be required for an expansion of BA.2.75 over BA.4/5.
Subject(s)
Severe Acute Respiratory SyndromeABSTRACT
COVID-19 strongly influences our daily lives, and there is urgent need for a therapy treating early infections to prevent progression.CARVIN was a randomized, parallel, double-blind, placebo-controlled study. Ninety SARS-CoV-2 positive patients were randomized into 3 groups receiving placebo, 0·02% or 0·1% azelastine nasal spray for 11 days, during which viral loads were assessed by quantitative PCR. Investigators assessed patients’ status throughout the trial including safety follow-ups (days 16 and 60). Symptoms were documented in patient diaries.Initial viral loads were log10 6·85 ± 1·31 (mean ± SD) copies/mL (ORF 1a/b gene). After treatment, virus load was reduced in all groups (p<0·0001), but was greater in the 0·1% group compared to placebo (p=0·007). In a subset of patients (initial Ct<25) viral load was strongly reduced on day 4 in the 0·1% group compared to placebo (p=0·005). Negative PCR results appeared earlier and more frequently in the azelastine treated groups: being 18·52% and 21·43% in the 0·1% and 0·02% groups, respectively, compared to 0% for placebo on day 8. Comparable numbers of adverse events occurred in all treatment groups with no safety concerns.The shown effects of azelastine nasal spray may thus be suggestive of azelastine’s potential as an antiviral treatment.Trial Registration:The study was registered in the German Clinical Trial Register (DRKS-ID: DRKS00024520; Date of Registration in DRKS: 12/02/2021).EudraCT number: 2020-005544-34
Subject(s)
COVID-19ABSTRACT
ABSTRACT Objective To determine the immediate need for a fourth COVID-19 vaccination based on the neutralizing capacity in patients on methotrexate (MTX) therapy after mRNA booster immunization. Methods In this observational cohort study, neutralizing serum activity against SARS-CoV-2 wildtype (Wu01) and variant of concern (VOC) Omicron BA.1 and BA.2 were assessed by pseudovirus neutralization assay before, 4 and 12 weeks after mRNA booster immunization in 50 rheumatic patients on MTX, 26 of whom paused the medication. 44 non-immunosuppressed persons (NIP) served as control group. Results While the neutralizing serum activity against SARS-CoV-2 Wu01 and Omicron variants increased 67-to 73-fold in the NIP after booster vaccination, the serum activity in patients receiving MTX increased only 20-to 23-fold. As a result, significantly lower neutralizing capacities were measured in patients on MTX compared to the NIP at week 4. Patients who continued MTX treatment during vaccination had significantly lower neutralizing serum titres against all three virus strains at week 4 and 12 compared to patients who paused MTX and the control group, except for BA.2 at week 12. Patients who paused MTX reached comparably high neutralization titres as the NIP, except for Wu01 at week 12. Neutralization of omicron variants was significantly lower in comparison to wildtype in both groups. Conclusion Patients pausing MTX showed a similar vaccine response to NIP. Patients who continued MTX demonstrated an impaired booster response indicating a potential benefit of a second booster vaccination.
Subject(s)
COVID-19ABSTRACT
The novel coronavirus pandemic, whose first outbreak was reported in December 2019 in Wuhan, China (COVID-19), is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Tissue damage caused by the virus leads to a strong immune response and activation of antigen-presenting cells, which can elicit acute respiratory distress syndrome (ARDS) characterized by the rapid onset of widespread inflammation, the so-called cytokine storm. In many viral infections the recruitment of monocytes into the lung and their differentiation to dendritic cells (DCs) are seen as a response to the viral infection. DCs are critical players in the development of the acute lung inflammation that causes ARDS. Here we focus on the interaction of the ORF8 protein, a specific SARS-CoV-2 open reading frame protein, with dendritic cells (DCs). We show that ORF8 binds to dendritic cells, causes a pre-maturation of differentiating DCs, and induces the secretion of multiple pro-inflammatory cytokines by these cells. In addition, we identified dendritic cell-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN) as a possible interaction partner of ORF8 on dendritic cells. Blockade of ORF8 signaling leads to reduced production of IL-1{beta}, IL-6, IL-12p70, TNF-, MCP-1 (CCL2), and IL-10 by dendritic cells. Analysis of patient sera with high anti-ORF8 antibody titers showed that there was nearly no neutralization of the ORF8 protein and its function. Therefore, a neutralizing antibody that has the capacity of blocking the cytokine and chemokine response mediated by ORF8 protein might be an essential and novel additional step in the therapy of severe SARS-CoV-2 cases.
Subject(s)
Inflammation , Virus Diseases , Respiratory Distress Syndrome , Pneumonia , Coronavirus Infections , COVID-19ABSTRACT
SARS-CoV-2-neutralizing antibodies play a critical role for protection and treatment of COVID-19. Viral antibody evasion therefore threatens essential prophylactic and therapeutic measures. The high number of mutations in the Omicron BA.1 sublineage results in markedly reduced neutralization susceptibility. Consistently, Omicron is associated with lower vaccine effectiveness and a high re-infection rate. Notably, newly emerging Omicron sublineages (BA.1.1, BA.2) have rapidly become dominant. Here, we determine polyclonal serum activity against BA.1, BA.1.1 and BA.2 in 50 convalescent or vaccinated individuals as well as delineate antibody sensitivities on a monoclonal level using 163 antibodies. Our study reveals a significant but comparable reduction of serum activity against Omicron sublineages which markedly increases after booster immunization. However, notable differences in sensitivity to individual antibodies demonstrate distinct escape patterns of BA.1 and BA.2 that also affect antibodies in clinical use. The results have strong implications for vaccination strategies and antibody use in prophylaxis and therapy.
Subject(s)
COVID-19ABSTRACT
SARS-CoV-2 mRNA vaccination of healthy individuals is highly immunogenic and protective against severe COVID-19. However, there are limited data on how disease-modifying therapies (DMTs) alter SARS-CoV-2 mRNA vaccine immunogenicity in patients with autoimmune diseases. Here we investigated the induction and stability of vaccine-specific antibodies, B cells, and T cells in multiple sclerosis (MS) patients on different DMTs in a prospective cohort study up to 6 months after homologous prime-boost mRNA vaccination. We analysed 103 MS patients of which 86 received anti-CD20-based B cell depletion (aCD20-BCD), fingolimod, interferon-β, dimethyl fumarate, glatiramer acetate, teriflunomide or natalizumab, and compared them to 17 untreated MS patients. In contrast to all other DMTs and untreated patients, treatment with aCD20-BCD or fingolimod significantly reduced anti-S1 IgG, serum neutralizing activity, and RBD- and S2-specific B cells. MS patients receiving fingolimod additionally lacked S1- and S2-reactive CD4 + T cell responses. The duration of fingolimod treatment, rather than peripheral blood B and T cell counts prior to vaccination, determined whether patients successfully developed humoral immune responses. Fingolimod blocks the ability of immune cells to recirculate and migrate within secondary lymphoid organs demonstrating that functional immune responses require not only immune cells themselves but also access of these cells to the site of inoculation and their unimpeded movement. The absence of humoral and T cell responses in fingolimod-treated MS patients suggests that these patients are at risk for severe SARS-CoV-2 infections despite vaccination, which is highly relevant for clinical decision-making and adapted protective measures, particularly in light of additional recently approved S1P receptor antagonists for MS treatment.
Subject(s)
Multiple Sclerosis , Autoimmune Diseases , COVID-19ABSTRACT
Systematic SARS-CoV-2 testing is a valuable tool for infection control and surveillance. However, broad application of high sensitive RT-qPCR testing in children is often hampered due to unpleasant sample collection, limited RT-qPCR capacities, and high costs. Here, we developed a high-throughput approach (Lolli-Method) for sensitive SARS-CoV-2 detection in children, combining non-invasive sample collection with an RT-qPCR-pool testing strategy. SARS-CoV-2 infections were diagnosed with sensitivities of 100% and 93.9% when viral loads were >10E6 copies/ml and >10E3 copies/ml in corresponding Naso-/Oropharyngeal-swabs, respectively. For effective application of the Lolli-Method in schools and daycare facilities, SIR-modeling indicated a preferred frequency of two tests per week. The developed test strategy was implemented in 3,700 schools and 698 daycare facilities in Germany, screening over 800,000 individuals twice per week. In a period of 3 months, 6,364 pool-RT-qPCRs tested positive (0.64%) ranging from 0.05% to 2.61% per week. Notably, infections correlated with local SARS-CoV-2 incidences as well as with a school social deprivation index. Moreover, in comparison with the alpha variant, statistical modeling revealed a 31% increase for multiple (>1 child) infections per class following infections with the delta variant. We conclude that the Lolli-Method is a powerful tool for SARS-CoV-2 surveillance and infection control in schools and daycare facilities.
Subject(s)
Severe Acute Respiratory Syndrome , Sleep Deprivation , COVID-19ABSTRACT
Elderly individuals are at high risk for severe COVID-19. Due to modest vaccine responses compared to younger individuals and the time elapsed since prioritized vaccinations, the emerging immune-evasive Omicron variant of SARS-CoV-2 is a particular concern for the elderly. Here we longitudinally determined SARS-CoV-2-neutralizing serum activity against different variants in a cohort of 37 individuals with a median age of 82 years. Participants were followed for 10 months after an initial two-dose BNT162b2 vaccination and up to 4.5 months after a BNT162b2 booster. Detectable Omicron-neutralizing activity was nearly absent after two vaccinations but elicited in 89% of individuals by the booster immunization. Neutralizing titers against the Wu01, Delta, and Omicron variants showed similar post-boost declines and 81% of individuals maintained detectable activity against Omicron. Our study demonstrates the mRNA booster effectiveness in inducing Omicron neutralizing activity and provides critical information on vaccine response durability in the highly vulnerable elderly population.
Subject(s)
COVID-19ABSTRACT
The Omicron variant of SARS-CoV-2 is causing a rapid increase in infections across the globe. This new variant of concern carries an unusually high number of mutations in key epitopes of neutralizing antibodies on the viral spike glycoprotein, suggesting potential immune evasion. Here we assessed serum neutralizing capacity in longitudinal cohorts of vaccinated and convalescent individuals, as well as monoclonal antibody activity against Omicron using pseudovirus neutralization assays. We report a near-complete lack of neutralizing activity against Omicron in polyclonal sera from individuals vaccinated with two doses of the BNT162b2 COVID-19 vaccine and from convalescent individuals, as well as resistance to different monoclonal antibodies in clinical use. However, mRNA booster immunizations in vaccinated and convalescent individuals resulted in a significant increase of serum neutralizing activity against Omicron. The presented study demonstrates that booster immunizations may be critical to substantially improve the humoral immune response against the Omicron variant.Authors Henning Gruell, Kanika Vanshylla, Florian Kurth, Leif E. Sander, and Florian Klein contributed equally to this work.
Subject(s)
COVID-19ABSTRACT
The Omicron variant of SARS-CoV-2 is causing a rapid increase in infections in various countries. This new variant of concern carries an unusually high number of mutations in key epitopes of neutralizing antibodies on the spike glycoprotein, suggesting potential immune evasion. Here we assessed serum neutralizing capacity in longitudinal cohorts of vaccinated and convalescent individuals, as well as monoclonal antibody activity against Omicron using pseudovirus neutralization assays. We report a near-complete lack of neutralizing activity against Omicron in polyclonal sera after two doses of the BNT162b2 vaccine, in convalescent individuals, as well as resistance to different monoclonal antibodies in clinical use. However, mRNA booster immunizations in vaccinated and convalescent individuals resulted in a significant increase of serum neutralizing activity against Omicron. Our study demonstrates that booster immunizations will be critical to substantially improve the humoral immune response against the Omicron variant.
ABSTRACT
Pre-existing immunity against SARS-CoV-2 may have critical implications for our understanding of COVID-19 susceptibility and severity. Various studies recently provided evidence of pre-existing T cell immunity against SARS-CoV-2 in unexposed individuals. In contrast, the presence and clinical relevance of a pre-existing B cell immunity remains to be fully elucidated. Here, we provide a detailed analysis of the B cell response to SARS-CoV-2 in unexposed individuals. To this end, we extensively investigated the memory B cell response to SARS-CoV-2 in 150 adults sampled pre-pandemically. Comprehensive screening of donor plasma and purified IgG samples for binding and neutralization in various functional assays revealed no substantial activity against SARS-CoV-2 but broad reactivity to endemic betacoronaviruses. Moreover, we analyzed antibody sequences of 8,174 putatively SARS-CoV-2-reactive B cells on a single cell level and generated and tested 158 monoclonal antibodies. None of the isolated antibodies displayed relevant binding or neutralizing activity against SARS-CoV-2. Taken together, our results show no evidence of relevant pre-existing antibody and B cell immunity against SARS-CoV-2 in unexposed adults.
Subject(s)
COVID-19ABSTRACT
COVID-19 mRNA vaccine BNT162b2 is highly immunogenic and effective, but recent studies have indicated waning anti-SARS-CoV-2 immune responses over time. Increasing infection rates has led authorities in several countries to initiate booster campaigns for vulnerable populations, including the elderly. However, the durability of vaccine-induced immunity in the elderly is currently unknown. Here, we describe interim results of a prospective cohort study comparing immune responses in a cohort of vaccinated elderly persons to those in healthcare workers (HCW), measured six months after first immunisation with BNT162b2. Anti-SARS-CoV-2 S1-, full Spike- and RBD-IgG seropositivity rates and IgG levels at six months were significantly lower in the elderly compared to HCW. Serum neutralization of Delta VOC measured by pseudovirus neutralisation test was detectable in 43/71 (60.6%, 95%CI: 48.9-71.1) in the elderly cohort compared to 79/83 in the HCW cohort (95.2%, 95%CI: 88.3-98.1) at six months post vaccination. Consistent with the overall lower antibody levels, SARS-CoV-2-S1 T cell reactivity was reduced in the elderly compared to HCW (261.6 mIU/ml, IQR:141.5-828.6 vs 1198.0 mIU/ml, IQR: 593.9-2533.6, p<0.0001). Collectively, these findings suggest that the established two-dose vaccination regimen elicits less durable immune responses in the elderly compared to young adults. Given the recent surge in hospitalisations, even in countries with high vaccination rates such as Israel, the current data may support booster vaccinations of the elderly. Further studies to determine long-term effectiveness of COVID-19 vaccines in high-risk populations and the safety and effectiveness of additional boosters are needed.
Subject(s)
COVID-19ABSTRACT
Despite recent availability of vaccines against severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2), there is an urgent need for specific anti-SARS-CoV-2 drugs. Monoclonal neutralizing antibodies are an important drug class in the global fight against the SARS-CoV-2 pandemic due to their ability to convey immediate protection and their potential to be used as both, prophylactic and therapeutic drugs. Clinically used neutralizing antibodies against respiratory viruses are currently injected intravenously, which can lead to suboptimal pulmonary bioavailability and thus to a lower effectiveness. Here we describe DZIF-10c, a fully human monoclonal neutralizing antibody that binds the receptor-binding domain of SARS-CoV-2 spike protein. DZIF-10c displays an exceptionally high neutralizing potency against SARS-CoV-2 and retains activity against the variants of concern B.1.1.7 and B.1.351. Importantly, not only systemic but also intranasal application of DZIF-10c abolished presence of infectious particles in the lungs of SARS-CoV-2 infected mice and mitigated lung pathology. Along with a favorable pharmacokinetic profile, these results highlight DZIF-10c as a novel human SARS-CoV-2 neutralizing antibody with high in vitro and in vivo antiviral potency. The successful intranasal application of DZIF-10c paves the way for clinical trials investigating topical delivery of anti-SARS-CoV-2 antibodies.
Subject(s)
Coronavirus Infections , Severe Acute Respiratory Syndrome , COVID-19ABSTRACT
Background / Objectives: The global spread of SARS-CoV-2 is a serious public health issue. Large-scale surveillance screenings are crucial but can exceed diagnostic test capacities. We set out to optimize test conditions and implemented high throughput pool testing of respiratory swabs into SARS-CoV-2 diagnostics. Study design: In preparation for pool testing, we determined the optimal pooling strategy and pool size. In addition, we measured the impact of vortexing prior to sample processing, compared pipette- and swab-pooling method as well as the sensitivity of three different PCR assays. Results: Using optimized strategies for pooling, we systematically pooled 55,690 samples in a period of 44 weeks resulting in a reduction of 47,369 PCR reactions. In a low prevalence setting, we defined a preferable pool size of ten in a two-stage hierarchical pool testing strategy. Vortexing of the swabs increased cellular yield by a factor of 2.34, and sampling at or shortly after symptom onset was associated with higher viral loads. By comparing different pooling strategies, pipette-pooling was more efficient compared to swab-pooling. Conclusions: For implementing pooling strategies into high throughput diagnostics, we recommend to apply a pipette-pooling method, using pool sizes of ten samples, performing sensitivity validation of the PCR assays used, and vortexing swabs prior to analyses. Our data shows, that pool testing for SARS-CoV-2 detection is feasible and highly effective in a low prevalence setting.