An illustration, based on the crystal structure from the study by Augusto et al., 2023 (Nature), shows the NQK-Q8 peptide, part of the SARS-CoV-2 spike protein, interacting with the HLA-B*15:01 groove. This interaction is key to understanding asymptomatic COVID-19 infections. The image is credited to André Luiz Lourenço.
Recent research indicates that a genetic variation common among individuals plays a crucial role in determining who remains asymptomatic after contracting SARS-CoV-2.
The puzzle of why certain people never show symptoms of COVID-19 might be closer to being solved. A collaborative study between the U.S. and Australia, led by researchers Danillo Augusto, Ph.D., from the University of North Carolina at Charlotte; Jill Hollenbach, Ph.D., from the University of California San Francisco; and Stephanie Gras from La Trobe University in Australia, has been published in Nature. This study reveals that a frequent genetic variation is the key factor in controlling asymptomatic infections of SARS-CoV-2.
Understanding Human Leukocyte Antigens (HLA)
The focus of the study is on human leukocyte antigens (HLA) genes, which are vital for the immune system to recognize and combat infected cells. HLAs vary significantly among people, raising the question of whether certain variants could influence susceptibility or resistance to the SARS-CoV-2 virus.
Research Findings and Approach
The research, spearheaded by Hollenbach, began at the pandemic’s onset. It involved screening 29,947 unvaccinated individuals for COVID-19 symptoms using a specialized mobile app. Of these, 1,428 tested positive. DNA sequencing was used to analyze their HLA genes. The findings showed that the presence of the HLA-B*15:01 genetic variant correlated with a higher likelihood of remaining asymptomatic after infection. This variant is found in approximately 10% of the population.
Insights into Immune Response
The researchers propose that people with this genetic variant might have an immune system that responds so swiftly and effectively to the virus that symptoms are prevented. They compare this to an army pre-trained to recognize and combat the enemy.
Cross-Reactive Immunological Responses
The study also explores the concept of cross-reactive immunological responses. It suggests that exposure to other coronaviruses in the past may have equipped individuals, especially those with the HLA-B*15:01 variant, to effectively fight off SARS-CoV-2. This ability is likened to recognizing an enemy by distinctive features like boots or tattoos, despite changes in their uniform.
The study identified a specific SARS-CoV-2 particle recognized by this HLA variant in individuals who had not been exposed to the virus. It was found to be similar to particles from other coronaviruses, indicating that pre-existing T cells could recognize and respond to SARS-CoV-2 just as efficiently.
Implications and Future Research
This research opens doors to understanding how some people avoid sickness from SARS-CoV-2 and has implications for future studies in COVID-19 treatments and vaccines.
For more details, refer to the article titled “Unmasking the Secret of COVID-19 ‘Super Dodgers.’”
The study cited is “A common allele of HLA is associated with asymptomatic SARS-CoV-2 infection” by Danillo G. Augusto et al., published on July 19, 2023, in Nature.
Frequently Asked Questions (FAQs) about Asymptomatic COVID-19
What is the key finding of the recent COVID-19 study?
The study, led by researchers Danillo Augusto, Jill Hollenbach, and Stephanie Gras, found that a common genetic variation, specifically the HLA-B*15:01 gene, plays a crucial role in determining why some individuals remain asymptomatic after contracting SARS-CoV-2.
How does the HLA-B*15:01 gene affect COVID-19 infection?
Individuals with the HLA-B*15:01 genetic variant are more likely to remain asymptomatic after a SARS-CoV-2 infection. This is due to the variant’s influence on the immune system’s ability to recognize and combat the virus effectively without developing symptoms.
What methodology was used in the COVID-19 study?
The study involved screening 29,947 unvaccinated individuals using a mobile app designed to track COVID-19 symptoms. Of these, 1,428 who tested positive for the virus had their DNA sequenced to analyze their HLA genes, leading to the discovery of the HLA-B*15:01 variant’s impact.
What are the implications of this study for future COVID-19 research?
The findings provide insights into the mechanisms of immune response to SARS-CoV-2, potentially guiding future research in COVID-19 therapeutics and vaccines. Understanding the role of HLA-B*15:01 in immunity may help in developing strategies to combat the virus more effectively.
More about Asymptomatic COVID-19
- Understanding Asymptomatic COVID-19
- HLA-B*15:01 and Its Role in Immunity
- Methodology of COVID-19 Genetic Study
- Implications of HLA-B*15:01 Research for COVID-19 Treatment and Vaccines