An international team of researchers has discovered that the Omicron variants of the SARS-CoV-2 virus have a superior capability to attach to cells and circumvent antibodies in comparison to their predecessors. Nonetheless, the study emphasizes that previous exposure to the virus or inoculation still confers a measure of protection against acute illness caused by these new variants.
The Omicron strains, known for their rapid global dissemination, exhibit heightened efficiency both in cellular attachment and in evading antibody response compared to earlier forms of the virus.
Recent research, led by a global assembly of scientists and published in the scientific journal Nature, reveals that the Omicron variants latch onto human cells with greater tenacity, penetrate them more adeptly, and manage to avoid many of the antibodies generated by earlier infections or vaccinations.
The study was helmed by Amin Addetia, a graduate scholar, and Young-Jun Park, a scientific researcher, both working under the supervision of David Veesler, Professor of Biochemistry at the University of Washington School of Medicine. Additional lead authors included Luca Picolli, Director of Humabs BioMed in Bellinzona, Switzerland, and James Brett Case from Washington University School of Medicine in St. Louis. Veesler, who also holds a position as a Howard Hughes Medical Institute Investigator, supervised the research endeavor.
David Veesler noted that dominant Omicron variants like BQ.11 and XBB.1.5 exhibit a stronger affinity for the angiotensin-converting enzyme 2 receptor on host cells, enabling them to merge with cellular membranes and infiltrate cells more proficiently than earlier SARS-CoV-2 variants.
Since the initial outbreak of SARS-CoV-2 in Wuhan, China, in 2019, the virus has undergone constant evolution, producing continually emerging strains. Some of these have demonstrated lower adaptability, which has restricted their proliferation. However, other, more competent strains have led to resurgences in infections and mortality rates.
The primary Omicron variant, identified as BA.1, has been succeeded by a lineage of variants with mutations that enhance their infectivity and transmissibility. These comprise variants like BA.2, BA.4, BA.5, BQ.1.1, and XBB along with its sub-variants XBB.1 and XBB.1.5.
The research also identifies that these new variants can reinfect individuals previously afflicted by older strains and can bypass the immunity conferred by vaccines aimed at those older variants. The ability to escape detection by antibodies generated through earlier exposures was a critical finding made by Veesler and his team. These antibodies, termed neutralizing antibodies, usually function by rapidly eliminating the invading virus.
Despite this, the study found that prior infections or vaccinations do generate antibodies that can identify certain proteins on newer variants, leading to the activation of immune cells that can subsequently eliminate the infection.
This might account for why earlier exposure or vaccination against earlier variants seems to diminish the risk of severe disease, hospitalization, or fatality upon re-exposure to a new variant, according to Veesler.
Although most antibodies against older variants saw diminished neutralizing activity, one specific antibody, S309, retained its efficacy. This antibody targets a stable region on the viral spike protein, which tends to remain consistent across variants.
Veesler elaborated that the immune system’s tendency to produce antibodies based on previous exposures rather than generating new, variant-specific antibodies could be due to a mechanism known as immune imprinting. This phenomenon can compromise the immune system’s efficacy against new variants and emphasizes why future vaccines should be free from components of older variants that could facilitate immune imprinting.
The research, dated 30 August 2023, was partially supported by the U.S. National Institutes of Health, the U.S. National Institute of Allergy and Infectious Diseases, the Burroughs Wellcome Fund, the Swiss Kidney Foundation, and the Research Council of Cantonal Hospital Aarau in Haru, Switzerland. The study is catalogued under DOI: 10.1038/s41586-023-06487-6 in the journal Nature.
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Frequently Asked Questions (FAQs) about It appears that your last message is empty. If you have further questions or need additional information, please feel free to ask.
What does the new study reveal about Omicron variants of SARS-CoV-2?
The study, conducted by an international team of researchers and published in the journal Nature, indicates that Omicron variants have an increased ability to bind to human cells and to evade antibodies generated by prior infections or vaccinations.
Who were the key contributors to this study?
The lead authors include Amin Addetia, a graduate scholar, and Young-Jun Park, a research scientist, both working under the supervision of David Veesler, Professor of Biochemistry at the University of Washington School of Medicine. Additional key authors were Luca Picolli, Director of Humabs BioMed in Bellinzona, Switzerland, and James Brett Case from Washington University School of Medicine in St. Louis.
Does prior exposure to the virus or vaccination offer any protection against Omicron variants?
Yes, the study suggests that while Omicron variants are better at evading antibodies, previous exposure to the SARS-CoV-2 virus or vaccinations against it still offer some level of protection against severe illness caused by these new variants.
What is the significance of the antibody S309 mentioned in the study?
The antibody S309 targets a stable region on the spike protein of the virus, which tends to remain consistent across different variants. Its effectiveness is therefore retained, making it a crucial focus in the development of future vaccines or treatments.
How do Omicron variants impact those who have already been infected or vaccinated?
Omicron variants have the ability to reinfect people who had previously been infected by earlier variants of the virus. They can also bypass the immunity conferred by vaccines designed to protect against earlier strains.
What is immune imprinting and why is it important?
Immune imprinting is a phenomenon where the immune system’s response to a new infection is influenced by its previous interactions with similar viruses. This can potentially make the immune system less effective in combating new variants and has implications for the design of future vaccines.
Who funded this research?
The research was partially funded by various institutions including the U.S. National Institutes of Health, the U.S. National Institute of Allergy and Infectious Diseases, the Burroughs Wellcome Fund, the Swiss Kidney Foundation, and the Research Council of Cantonal Hospital Aarau in Haru, Switzerland.
Where can one access the full study?
The complete study has been published in the journal Nature, and it is catalogued under DOI: 10.1038/s41586-023-06487-6 for those who wish to delve into the details.
More about It appears that your last message is empty. If you have further questions or need additional information, please feel free to ask.
- Nature Journal: Original Study on Omicron Variants
- U.S. National Institutes of Health
- U.S. National Institute of Allergy and Infectious Diseases
- Burroughs Wellcome Fund
- Swiss Kidney Foundation
- University of Washington School of Medicine
- Washington University School of Medicine in St. Louis
- Humabs BioMed
