Patients exposed to a coronavirus may develop a multi-functional, cross-reactive coronavirus antibody; this may be useful for the final development of a broad-acting vaccine.
There are seven types of human coronavirus, of which, four cause the common cold, named OC43, HKU1, 229E, and NL63. Most people are infected with at least one in four coronaviruses at some point in their lives. Severe acute respiratory tract coronavirus 2 (SARS-CoV-2) is another member of the coronavirus family that causes COVID-19. Infection with cold sores coronaviruses can lead to memory impairment. This can have an immune effect response to COVID-19.
The research published in Environmental Communications compared blood samples of patients collected before the pandemic with those that tested positive for COVID-19. Through this, the researchers found antibody types that cross other coronaviruses and SARS-CoV-2.
Cross-reactive coronavirus antibody produced during SARS-CoV-2 infection
It is known that a cross-reactive coronavirus antibody is induced as a direct result of COVID-19 infection. Dr Raiees Andrabi, a senior author of the paper, stated, “We know that this type of cross-reactive antibody can be produced in a memory B cell that was first exposed to a coronavirus factor. in the common cold, and then recalled during COVID-19 infection. ”
Memory B cells can live a long life, as they can circulate throughout the body for decades to identify and fight pathogens they have previously encountered. Memory B cells offer protection against infiltration as well by rapidly producing specific antibodies. Although the study found evidence of pre-existing cross-reactive memory B cells aroused during SARS-CoV-2 infection, there was only weak evidence of pre-existing SARS-CoV-2 cross -reactive serum antibodies in pre-pandemic patient samples However, the researchers identified cross-reactive antibody neutralization specific to the S2 subunit of the spike (S) protein.
How does this antibody work?
The researchers used electron microscopy to determine how the cross-reactive antibody had the ability to neutralize several coronaviruses, including SARS-CoV-2. They found that the antibody is often bound to the S protein in the virus. This area does not seem to be different from the different types of coronavirus.
Ge Song, the paper’s first author, stated, “The study highlights how important it is to fully understand the nature of old stability, especially with respect to coronaviruses. Earlier exposure to a coronavirus, even a virus that causes a cold sore, affecting the nature and levels of antibodies produced when more severe coronavirus threats emerge. “
Meaning of study
Since immune memory has become the basis of vaccination, the findings of this study may be relevant to the development of a vaccine or antibody treatment that will act against most or all coronaviruses. Previous resistance to endemic coronaviruses should be further examined to assess antibody responses to SARS-CoV-2.
Co-author Dr Dennis Burton explains, “Another deadly coronavirus is likely to re-emerge in the future-and if it does, we want to be more prepared. Our identification of a cross-reactive antibody against SARS-CoV-2 and the more common coronavirus is a good progression toward an offensive vaccine or therapy. “
Kanta, G., et al. (2021). Cross-reactive serum and memory B-cell responses to the protein spike in SARS-CoV-2 and endemic coronavirus infection. Environmental Communications, 12 (1), 1-10. Retrieved from: https://www.nature.com/articles/s41467-021-23074-3
The versatile coronavirus antibody could be the starting point for more widely operational vaccines (2021). EurekAlert! Retrieved from: https://www.eurekalert.org/pub_releases/2021-05/sri-vca052721.php
Quast, I. and Tarlinton, D. (2021). B cell memory: understanding COVID-19. Safety, 54 (2), 205-210. Retrieved from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7826135/
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