Test Your Knowledge
9 Questions
3 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the potential impact of pre-existing cross-reactive antibodies on SARS-CoV-2 serosurveillance and disease diagnosis?

Pre-existing cross-reactive antibodies can interfere with serosurveillance and disease severity diagnosis.

What percentage of pre-pandemic serum samples from Zimbabwean adults have been found to have pre-existing antibodies that cross-react with SARS-CoV-2?

32%.

What is the potential reason for the low burden of COVID-19 in Africa compared to other continents?

  • Lower population density
  • Better healthcare infrastructure
  • Previous exposure to other pathogens that induce protective cross-immunity (correct)
  • Lack of testing facilities
  • What is the potential reason for the low burden of COVID-19 in Africa compared to other continents?

    <p>The low burden of COVID-19 in Africa compared to other continents could be due to previous exposure to other pathogens that induce protective cross-immunity.</p> Signup and view all the answers

    Why is it important to consider cross-reactive antibodies when interpreting SARS-CoV-2 seroepidemiology studies and evaluating outcomes of COVID-19 vaccine trials in Africa?

    <p>Cross-reactive antibodies can interfere with serosurveillance and disease severity diagnosis, and could potentially offer some level of protection against SARS-CoV-2.</p> Signup and view all the answers

    What was the aim of the study conducted in Zimbabwe?

    <p>To investigate pre-existing antibodies cross-reactive with SARS-CoV-2</p> Signup and view all the answers

    What statistical software was used in the study to obtain Z scores for each population?

    <p>Statistical software (v.20.4.0).</p> Signup and view all the answers

    What were the peptides reactive with IgG and IgM identified in the study?

    <p>Spike, nucleocapsid, and polyprotein 1AB proteins</p> Signup and view all the answers

    What method did the study use to screen the serum samples for reactivity against the peptides from the proteomes of the seven human coronaviruses?

    <p>The study used a PEPperCHIP Coronavirus Discovery Microarray to screen the serum samples for reactivity against the peptides from the proteomes of the seven human coronaviruses.</p> Signup and view all the answers

    Study Notes

    • Pre-existing antibodies that cross-react with SARS-CoV-2 have been found in 32% of pre-pandemic serum samples from Zimbabwean adults.
    • These cross-reactive antibodies can interfere with serosurveillance and disease severity diagnosis.
    • The antibodies could potentially offer some level of protection against SARS-CoV-2.
    • The low burden of COVID-19 in Africa compared to other continents could be due to previous exposure to other pathogens that induce protective cross-immunity.
    • Cross-reactive antibodies should be considered when interpreting SARS-CoV-2 seroepidemiology studies and evaluating outcomes of COVID-19 vaccine trials in Africa.
    • There are seven types of coronaviruses that naturally infect humans.
    • The common cold viruses have low pathogenicity while SARS and MERS coronaviruses can cause severe respiratory illness.
    • The study calls for further characterisation of SARs-CoV-2 immune phenotypes and responses in African populations.
    • Antibodies for other coronaviruses have been shown to last as long as 34 months.
    • There is potential for pre-existing natural IgM antibodies being protective against infection.
    • A study aimed to identify pre-existing antibodies that cross-react with peptides from all seven human coronaviruses in serum samples collected from a cross-section of Zimbabweans before the SARS-CoV-2 pandemic in November 2019.
    • The study aimed to determine the peptide epitopes of all proteins from the seven coronaviruses reactive with pre-SARS CoV-2 serum samples collected from Zimbabwe covering a period of 19 years between 2000 and 2019.
    • The study aimed to determine the potential antigenic sources that stimulated cross-reactivity with the SARS-CoV-2 peptide epitopes in the pre-SARS-CoV-2 serum samples.
    • The study used a PEPperCHIP Coronavirus Discovery Microarray to screen the serum samples for reactivity against the peptides from the proteomes of the seven human coronaviruses.
    • The test detects the presence of IgM and IgG antibodies directed against the nucleocapsid and the spike proteins of the SARS-CoV-2 virus.
    • The manufacturer indicated that the test had a clinical sensitivity of over 98% for SARS-CoV-2 infection.
    • The study found that the numbers of COVID-19 cases and deaths in Africa have been less than that in other continents.
    • The study identified conserved regions between peptides reactive with the serum samples and known B-cell epitopes from other immunogens (pathogens, allergens, and autoantigens).
    • The study used statistical software (v.20.4.0) to obtain Z scores for each population.
    • The study had ethical approval for the parent study.
    • A study was conducted in Zimbabwe to investigate pre-existing antibodies cross-reactive with SARS-CoV-2.
    • 339 pre-pandemic serum samples were collected in November 2019 from two rural villages in northeastern Zimbabwe.
    • The samples were cross-reactive with SARS-CoV-2 antigens on antibody-based COVID-19 rapid diagnostic tests (RDTs).
    • The study identified peptides on human coronaviruses that these antibodies were cross-reactive with.
    • The most reactive samples across all the samples were from an 11-year-old individual collected in 2006.
    • IgM in serum across all the Zimbabwean samples tended to recognise peptides with a high frequency of lysine.
    • The IgG responses were generally lower than IgM responses.
    • The study found that antibodies cross-reactive with SARS-CoV-2 peptides had been stimulated by antigens or immunogens from other sources, potentially other coronaviruses and autoantigens.
    • The study obtained ethical approval from the Medical Research Council of Zimbabwe and the Scotland A Research Ethics Committee.
    • The study used a positive control sample from a convalescent adult male in the UK with a high IgG titre against SARS-CoV-2 S1 spike protein and the nucleocapsid protein.
    • Study analyzed serum samples from Zimbabwe for reactivity to SARS-CoV-2 proteins.
    • Peptides reactive with IgG and IgM were identified in spike, nucleocapsid, and polyprotein 1AB proteins.
    • Some peptides shared partial sequences with other known B-cell antigens from other pathogens.
    • Spike protein had the least number of peptides with homologous motifs to non-SARS-CoV-2 proteins.
    • Nucleocapsid protein peptides shared motifs with nucleocapsid protein peptides from other betacoronaviruses, especially SARS-CoV and MERS-CoV.
    • Polyprotein 1AB peptides shared motifs with various human autoantigens, chaperone proteins, and allergens.
    • Some peptides shared motifs with human autoantigens and pathogens occurring in Zimbabwe, such as human betaherpes virus 6B and influenza A virus.
    • Several redundant peptides in the spike, polyprotein 1AB, and nucleocapsid proteins were shared with other betacoronaviruses and, to a lesser extent, alphacoronaviruses.
    • Similarities were found to pathogens that have not been reported in Zimbabwe including pangolin coronavirus, Trypanosoma cruzi, and Onchocerca volvulus.
    • The study provides insights into the immune response to SARS-CoV-2 in Zimbabwe and potential cross-reactivity with other pathogens.

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Description

    Test your knowledge about pre-existing antibodies cross-reactive with SARS-CoV-2 discovered in Zimbabwean adults with this informative quiz. Learn about the potential implications of these antibodies for serosurveillance and COVID-19 vaccine trials in Africa, and the possible protective effects of pre-existing antibodies against the virus. Explore the characteristics of the seven types of coronaviruses that naturally infect humans, and the cross-reactivity of antibodies to these viruses. Discover the peptide epitopes of all proteins from the

    More Like This

    Use Quizgecko on...
    Browser
    Browser