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1.
iScience ; 25(3): 103951, 2022 Mar 18.
Article in English | MEDLINE | ID: covidwho-1747872

ABSTRACT

Preexisting immunity against SARS-CoV-2 may have critical implications for our understanding of COVID-19 susceptibility and severity. The presence and clinical relevance of a preexisting B cell immunity remain to be fully elucidated. Here, we provide a detailed analysis of the B cell immunity to SARS-CoV-2 in unexposed individuals. To this end, we extensively investigated SARS-CoV-2 humoral immunity 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 at a single cell level and generated and tested 158 monoclonal antibodies. None of these antibodies displayed relevant binding or neutralizing activity against SARS-CoV-2. Taken together, our results show no evidence of competent preexisting antibody and B cell immunity against SARS-CoV-2 in unexposed adults.

2.
EuropePMC;
Preprint in English | EuropePMC | ID: ppcovidwho-327432

ABSTRACT

Systematic SARS-CoV-2 testing is a valuable tool for infection control and surveillance 1 . 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 2–4 . 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 >10 6 copies/ml and >10 3 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 (≥2 children) infections per class following infections with the delta variant 5 . We conclude that the Lolli-Method is a powerful tool for SARS-CoV-2 surveillance and infection control in schools and daycare facilities.

3.
Clin Kidney J ; 15(1): 162-164, 2022 Jan.
Article in English | MEDLINE | ID: covidwho-1625375

ABSTRACT

The combination of coronavirus disease 2019 (COVID-19) pneumonia and pulmonary-renal syndrome due to ANCA-associated vasculitis (AAV) poses diagnostic uncertainty and a therapeutic dilemma. According to current limited knowledge of COVID-19, the application of commonly used drugs in AAV, cyclophosphamide (CYC) and rituximab (RTX), must be weighed carefully in active COVID-19 infection. We report a case of a 52-year-old male patient with concurrent severe COVID-19 pneumonia and acute relapse of pulmonary-renal syndrome due to AAV after recent RTX maintenance dose. The patient presented with severe hypoxaemia, complete B-cell depletion and severe acute respiratory syndrome coronavirus 2 viraemia. He was successfully treated with therapeutic plasma exchange employing COVID-19 convalescent plasma.

5.
Ann Neurol ; 91(1): 150-157, 2022 01.
Article in English | MEDLINE | ID: covidwho-1527416

ABSTRACT

This study was undertaken to assess whether SARS-CoV-2 causes a persistent central nervous system infection. SARS-CoV-2-specific antibody index and SARS-CoV-2 RNA were studied in cerebrospinal fluid following COVID-19. Cerebrospinal fluid was assessed between days 1 and 30 (n = 12), between days 31 and 90 (n = 8), or later than 90 days (post-COVID-19, n = 20) after COVID-19 diagnosis. SARS-CoV-2 RNA was absent in all patients, and in none of the 20 patients with post-COVID-19 syndrome were intrathecally produced anti-SARS-CoV-2 antibodies detected. The absence of evidence of SARS-CoV-2 in cerebrospinal fluid argues against a persistent central nervous system infection as a cause of neurological or neuropsychiatric post-COVID-19 syndrome. ANN NEUROL 2022;91:150-157.


Subject(s)
COVID-19/complications , Central Nervous System Infections/cerebrospinal fluid , Central Nervous System Infections/virology , RNA, Viral/cerebrospinal fluid , Adult , Aged , Aged, 80 and over , COVID-19/cerebrospinal fluid , Cognitive Dysfunction/cerebrospinal fluid , Cognitive Dysfunction/virology , Female , Germany , Humans , Male , Middle Aged , SARS-CoV-2
6.
Microorganisms ; 9(9)2021 Sep 13.
Article in English | MEDLINE | ID: covidwho-1410328

ABSTRACT

The alpha variant of the severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) is associated with higher transmissibility and possibly higher mortality compared with wild-type SARS-CoV-2. However, few data are available on the clinical course of infections with the alpha variant compared with wild-type SARS-CoV-2 in critically ill patients in intensive care units (ICUs). Therefore, we retrospectively analyzed patients admitted to our ICU due to SARS-CoV-2 Alpha variant infection and compared characteristics and course to patients with SARS-CoV-2 wild-type infection. The median age of patients with Alpha variant infections was 57 years compared to 62 years in the wild-type group. ICU survival was 41/80 (51%) in the Alpha variant group and 35/80 (44%) in the wild-type group (p = 0.429). Results of a matched-pair analysis based on age and sex illustrated that 45/58 patients (77.6%) in the Alpha variant group and 38/58 (65.5%) patients in the wild-type group required mechanical ventilation (p = 0.217). ICU survival was documented for 28/58 patients (48.3%) in the Alpha variant group and 27/58 patients (46.6%) in the wild-type group (p = 1). Thus, ICU mortality among patients with SARS-CoV-2 infections remains high. Although the Alpha variant group included younger patients requiring mechanical ventilation, no significant differences between patients with the SARS-CoV-2 Alpha variant and the SARS-CoV-2 wild-type, respectively, were detected with respect to clinical course and ICU mortality. For future VOCs, we believe it would be important to obtain valid and rapid data on the clinical course of critically ill patients who test positive for COVID-19 in order to perform appropriate epidemiological planning of intensive care capacity.

8.
Cell Host Microbe ; 29(6): 917-929.e4, 2021 06 09.
Article in English | MEDLINE | ID: covidwho-1213083

ABSTRACT

Understanding antibody-based SARS-CoV-2 immunity is critical for overcoming the COVID-19 pandemic and informing vaccination strategies. We evaluated SARS-CoV-2 antibody dynamics over 10 months in 963 individuals who predominantly experienced mild COVID-19. Investigating 2,146 samples, we initially detected SARS-CoV-2 antibodies in 94.4% of individuals, with 82% and 79% exhibiting serum and IgG neutralization, respectively. Approximately 3% of individuals demonstrated exceptional SARS-CoV-2 neutralization, with these "elite neutralizers" also possessing SARS-CoV-1 cross-neutralizing IgG. Multivariate statistical modeling revealed age, symptomatic infection, disease severity, and gender as key factors predicting SARS-CoV-2-neutralizing activity. A loss of reactivity to the virus spike protein was observed in 13% of individuals 10 months after infection. Neutralizing activity had half-lives of 14.7 weeks in serum versus 31.4 weeks in purified IgG, indicating a rather long-term IgG antibody response. Our results demonstrate a broad spectrum in the initial SARS-CoV-2-neutralizing antibody response, with sustained antibodies in most individuals for 10 months after mild COVID-19.


Subject(s)
Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , COVID-19/immunology , Adolescent , Adult , Aged , Cohort Studies , Female , Humans , Immunoglobulin G/immunology , Male , Middle Aged , SARS-CoV-2 , Time Factors , Young Adult
9.
Microorganisms ; 9(4)2021 Mar 31.
Article in English | MEDLINE | ID: covidwho-1159427

ABSTRACT

Background: The investigation of the antibody response to SARS-CoV-2 represents a key aspect in facing the COVID-19 pandemic. In the present study, we compared the new Immundiagnostik IDK® anti-SARS-CoV-2 S1 IgG assay with four widely-used commercial serological assays for the detection of antibodies targeting S (spike) and NC (nucleocapsid) proteins. Methods: Serum samples were taken from an unbiased group of convalescent patients and from a negative control group. Sample were simultaneously analyzed by the new Immundiagnostik IDK® anti-SARS-CoV-2 S1 IgG assay, by the DiaSorin LIAISON® SARS-CoV-2 S1/S2 IgG assay, and by the Euroimmun anti-SARS-CoV-2 S1 IgG ELISA. Antibodies binding NC were detected by the Abbott SARS-CoV-2 IgG assay and by the pan-immunoglobulin immunoassay Roche Elecsys® anti-SARS-CoV-2. Moreover, we investigated samples of a group of COVID-19 convalescent subjects that were primarily tested S1 IgG non-reactive. Samples were also tested by live virus and pseudovirus neutralization tests. Results: Overall, the IDK® anti-SARS-CoV-2 S1 IgG assay showed the highest sensitivity among the evaluated spike (S) protein-based assays. Additionally, the Immundiagnostik assay correlated well with serum-neutralizing activity. Conclusions: The novel IDK® anti-SARS-CoV-2 S1 IgG assay showed high sensitivity and specificity, representing a valid option for use in the routine diagnostic.

10.
Eur J Clin Microbiol Infect Dis ; 40(5): 1063-1071, 2021 May.
Article in English | MEDLINE | ID: covidwho-1061091

ABSTRACT

Evaluation and power of seroprevalence studies depend on the performed serological assays. The aim of this study was to assess four commercial serological tests from EUROIMMUN, DiaSorin, Abbott, and Roche as well as an in-house immunofluorescence and neutralization test for their capability to identify SARS-CoV-2 seropositive individuals in a high-prevalence setting. Therefore, 42 social and working contacts of a German super-spreader were tested. Consistent with a high-prevalence setting, 26 of 42 were SARS-CoV-2 seropositive by neutralization test (NT), and immunofluorescence test (IFT) confirmed 23 of these 26 positive test results (NT 61.9% and IFT 54.8% seroprevalence). Four commercial assays detected anti-SARS-CoV-2 antibodies in 33.3-40.5% individuals. Besides an overall discrepancy between the NT and the commercial assays regarding their sensitivity, this study revealed that commercial SARS-CoV-2 spike-based assays are better to predict the neutralization titer than nucleoprotein-based assays are.


Subject(s)
COVID-19 Serological Testing/methods , COVID-19/diagnosis , COVID-19/epidemiology , SARS-CoV-2/isolation & purification , Adolescent , Adult , Aged , Antibodies, Neutralizing/blood , Antibodies, Viral/blood , COVID-19/blood , COVID-19 Serological Testing/standards , Contact Tracing , Female , Humans , Immunoassay , Male , Middle Aged , Neutralization Tests , Prevalence , SARS-CoV-2/immunology , Sensitivity and Specificity , Young Adult
11.
PLoS One ; 15(11): e0238612, 2020.
Article in English | MEDLINE | ID: covidwho-902011

ABSTRACT

BACKGROUND: Rapid and extensive testing of large parts of the population and specific subgroups is crucial for proper management of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections and decision-making in times of a pandemic outbreak. However, point-of-care (POC) testing in places such as emergency units, outpatient clinics, airport security points or the entrance of any public building is a major challenge. The need for thermal cycling and nucleic acid isolation hampers the use of standard PCR-based methods for this purpose. METHODS: To avoid these obstacles, we tested PCR-independent methods for the detection of SARS-CoV-2 RNA from primary material (nasopharyngeal swabs) including reverse transcription loop-mediated isothermal amplification (RT-LAMP) and specific high-sensitivity enzymatic reporter unlocking (SHERLOCK). RESULTS: Whilst specificity of standard RT-LAMP assays appears to be satisfactory, sensitivity does not reach the current gold-standard quantitative real-time polymerase chain reaction (qPCR) assays yet. We describe a novel multiplexed RT-LAMP approach and validate its sensitivity on primary samples. This approach allows for fast and reliable identification of infected individuals. Primer optimization and multiplexing helps to increase sensitivity significantly. In addition, we directly compare and combine our novel RT-LAMP assays with SHERLOCK. CONCLUSION: In summary, this approach reveals one-step multiplexed RT-LAMP assays as a prime-option for the development of easy and cheap POC test kits.


Subject(s)
Betacoronavirus/genetics , Coronavirus Infections/diagnosis , Nucleic Acid Amplification Techniques/methods , Pneumonia, Viral/diagnosis , RNA, Viral/metabolism , Betacoronavirus/isolation & purification , COVID-19 , COVID-19 Testing , Clinical Laboratory Techniques , Coronavirus Infections/virology , Humans , Nasopharynx/virology , Pandemics , Pneumonia, Viral/virology , RNA, Viral/genetics , Real-Time Polymerase Chain Reaction , SARS-CoV-2 , Sensitivity and Specificity
12.
Viruses ; 12(9)2020 09 18.
Article in English | MEDLINE | ID: covidwho-789516

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) represents a global health emergency. To improve the understanding of the systemic component of SARS-CoV-2, we investigated if viral load dynamics in plasma and respiratory samples are associated with antibody response and severity of coronavirus disease 2019 (COVID-19). SARS-CoV-2 RNA was found in plasma samples from 14 (44%) out of 32 patients. RNAemia was detected in 5 out of 6 fatal cases. Peak IgG values were significantly lower in mild/moderate than in severe (0.6 (interquartile range, IQR, 0.4-3.2) vs. 11.8 (IQR, 9.9-13.0), adjusted p = 0.003) or critical cases (11.29 (IQR, 8.3-12.0), adjusted p = 0.042). IgG titers were significantly associated with virus Ct (Cycle threshold) value in plasma and respiratory specimens ((ß = 0.4, 95% CI (confidence interval, 0.2; 0.5), p < 0.001 and ß = 0.5, 95% CI (0.2; 0.6), p = 0.002). A classification as severe or a critical case was additionally inversely associated with Ct values in plasma in comparison to mild/moderate cases (ß = -3.3, 95% CI (-5.8; 0.8), p = 0.024 and ß = -4.4, 95% CI (-7.2; 1.6), p = 0.007, respectively). Based on the present data, our hypothesis is that the early stage of SARS-CoV-2 infection is characterized by a primary RNAemia, as a potential manifestation of a systemic infection. Additionally, the viral load in plasma seems to be associated with a worse disease outcome.


Subject(s)
Antibodies, Viral/blood , Betacoronavirus/isolation & purification , Coronavirus Infections/virology , Pneumonia, Viral/virology , RNA, Viral/blood , Aged , Betacoronavirus/genetics , Betacoronavirus/immunology , COVID-19 , Coronavirus Infections/blood , Coronavirus Infections/pathology , Female , Germany/epidemiology , Hospitalization , Humans , Immunoglobulin G/blood , Male , Middle Aged , Pandemics , Pneumonia, Viral/blood , Pneumonia, Viral/pathology , RNA, Viral/analysis , Respiratory System/virology , SARS-CoV-2 , Severity of Illness Index , Viral Load , Viremia/blood , Viremia/pathology , Viremia/virology
15.
Cell ; 182(4): 843-854.e12, 2020 08 20.
Article in English | MEDLINE | ID: covidwho-641071

ABSTRACT

The SARS-CoV-2 pandemic has unprecedented implications for public health, social life, and the world economy. Because approved drugs and vaccines are limited or not available, new options for COVID-19 treatment and prevention are in high demand. To identify SARS-CoV-2-neutralizing antibodies, we analyzed the antibody response of 12 COVID-19 patients from 8 to 69 days after diagnosis. By screening 4,313 SARS-CoV-2-reactive B cells, we isolated 255 antibodies from different time points as early as 8 days after diagnosis. Of these, 28 potently neutralized authentic SARS-CoV-2 with IC100 as low as 0.04 µg/mL, showing a broad spectrum of variable (V) genes and low levels of somatic mutations. Interestingly, potential precursor sequences were identified in naive B cell repertoires from 48 healthy individuals who were sampled before the COVID-19 pandemic. Our results demonstrate that SARS-CoV-2-neutralizing antibodies are readily generated from a diverse pool of precursors, fostering hope for rapid induction of a protective immune response upon vaccination.


Subject(s)
Antibodies, Neutralizing/isolation & purification , Antibodies, Viral/isolation & purification , Coronavirus Infections/immunology , Pneumonia, Viral/immunology , Antibodies, Neutralizing/genetics , Antibodies, Neutralizing/immunology , Antibodies, Viral/genetics , Antibodies, Viral/immunology , B-Lymphocytes/immunology , Betacoronavirus/immunology , COVID-19 , Humans , Immunoglobulin Variable Region/genetics , Immunoglobulin Variable Region/immunology , Immunologic Memory , Longitudinal Studies , Pandemics , SARS-CoV-2 , Somatic Hypermutation, Immunoglobulin
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