Link between inflammatory response and COVID-19?
COVID.
Undoubtedly one of the most frequently appearing words in headlines across the world these last 20 months – and for good reason. If we concentrate only on the Icelandic statistics, by the end of 2021 almost 20 thousand people had been infected with the SARS-CoV-2 virus, which causes the disease known as COVID-19. Almost 800 thousand tests have been taken in Iceland and almost 600 people have been admitted to hospital, including 95 people who required intensive care. At the time of writing this article, 37 people have died in Iceland from COVID-19. Looking at the global figures, around 270 million people have been infected and 5.3 million have died.
This pandemic represents the most significant challenge to face humankind for a long time. It has been a very difficult time for governments, institutions and infrastructure, healthcare systems and individuals. But it has also presented a huge challenge to scientists in all fields as they seek solutions, not least in the health sciences.
Although the virus has been causing havoc for almost two years now, continuing to mutate, we still have much to learn about its nature, how it will change in the future, and its long-term consequences. It is clear that COVID-19 and the coronavirus itself that causes the disease will be the subject of research for years and decades to come. This research will enable us to better tackle this virus and also other viruses and the diseases they cause.
Elevated cytokine levels in those who become seriously ill
"When the pandemic began in Iceland, we observed a significant increase in the cytokine IL-6 in individuals who became seriously ill with COVID-19. Cytokines are small proteins, secreted by cells in the immune system, that affect other cells in the body," explains Siggeir Fannar Brynjólfsson, lecturer at the UI Faculty of Medicine. Siggeir is one of a large number of scientists at the University now working on research related to COVID-19. Siggeir and his colleagues aim to explore whether there is a link between cytokine levels in the blood and the progression of the disease in those who become ill with COVID-19. "We also want to look at whether there is any connection between chronic COVID-19 symptoms and the release of cytokines."
Focus on the immune system
Siggeir teaches on a course in immunology at the University of Iceland and most of his research is in this field. His interests focus on the immune system, which has been a subject of much discussion in relation to vaccination against the SARS-CoV-2 coronavirus and also the body's response to infection with this virus.
The immune system is so called because it works to make us immune to certain pathogens. An article on the University of Iceland Web of Science explains that we only acquire immunity against a certain antigen from a pathogen (a microorganism that can cause disease) if our immune system comes into contact with the antigen itself and identifies it as a foreign substance. And what is an antigen? It is the part of the microorganism that induces an immune response once the immune system has identified it as a foreign substance. The immune system responds by producing antibodies and/or T-cells to fight the antigen. And what are T-cells? To simplify the concept, T-cells can be compared to soldier ants in an ant colony. T-cells immediately attack pathogens and infected cells, thereby activating and controlling the entire immune system.
The reason we become immune is that some of the cells that respond to the antigen with the appropriate antibodies and T-cells become memory cells, which can last for decades. When we are vaccinated, an antigen from a specific pathogen is introduced into the body, which activates the immune system without causing infection. We subsequently acquire new antibodies and T-cells that can fight the antigen.
"Memory cells recognise the pathogen if it later enters the body and fight it off before it can cause any harm. This means we don't become ill from the same pathogen again," explains the article on the Web of Science. This is a simplification for illustrative purposes, says Siggeir, explaining that the immune system is a fascinating and complex system.
"It doesn't matter which disease you look at, everything from arthritis to cancer, obesity or osteoporosis – the immune system always plays a key role. The pandemic has been difficult for all of us and we need to learn as much as we can about how the immune system responds to SARS-CoV-2 infection, as well as the factors that contribute to long-term effects of COVID-19 infection."
Although the virus has been causing havoc for almost two years now, continuing to mutate, we still have much to learn about its nature, how it will change in the future, and its long-term consequences. It is clear that COVID-19 and the coronavirus itself that causes the disease will be the subject of research for years and decades to come. This research will enable us to better tackle this virus and also other viruses and the diseases they cause. image//Wikipedia Commons
Important research into complex relationships
The COVID research by Siggeir and his colleagues is just one piece of a much larger puzzle that scientists at the UI Faculty of Medicine are working on in collaboration with scientists at Landspítali University Hospital and the Blood Bank.
"We have collected samples from over 450 people and our preliminary findings show correlations between elevated levels of various cytokines and age, sex and disease progression. We have also published a paper in which we measured SARS-CoV-2 specific antibodies using Luminex technology."
Siggeir explains that this technology works with coloured microbeads and lasers to quantify a specific protein. "We measured SARS-CoV-2 specific antibodies against different proteins of the virus. We saw that people who required intensive care were more likely to have high levels of IgA antibodies, which are the most important kind of antibody in the immune response of mucous membranes."
Siggeir says that the team are still hard at work and a paper presenting their initial findings will be published in a peer-reviewed journal shortly.
