Scientists have discovered a hidden mechanism that COVID-19 uses to circumvent the body's natural defenses and trigger a harmful inflammatory response in the lungs.
Scientists have found that the virus is able to hide inside small fragments of infected and dying cells, then invade immune cells and trigger an excessive inflammatory response that leads to severe damage to lung tissue.
The study, conducted by researchers from La Trobe University and the WEHI Institute in Australia and published in the prestigious scientific journal Nature Communications, found that the SARS-CoV-2 virus exploits a natural process by which the body gets rid of dead cells. Immune cells called macrophages devour these infected fragments, thinking they are just cellular waste, but the virus exploits this process to enter immune cells and spread among them without being detected in the usual way.
Lead researcher Dr. Kha Fan explains that the virus manages to bypass the main entry point known as ACE2 receptors, which are the virus's normal entry point into cells, and instead takes a hidden route through fragments of dying cells.
Once it enters immune cells, it moves between them stealthily, triggering a violent inflammatory response that causes serious damage to lung tissue.
The research team was able to use existing drugs – known as T-type calcium channel inhibitors – to repurpose them to prevent the formation of these infected cell fragments, which led to a reduction in viral spread, a decrease in harmful inflammation, and a significant reduction in lung damage in their experiments.
Researchers assert that this discovery fundamentally changes our understanding of viral infections, solving a long-standing scientific mystery about how COVID-19 manages to infect immune cells and trigger such devastating inflammation. They also suggest that similar mechanisms may exist in other respiratory viral diseases, such as influenza and respiratory syncytial virus (RSV), opening the door to a broader understanding of how these viruses interact with the human immune system.
This discovery could pave the way for the development of new treatments that are completely different from traditional antiviral drugs, as they do not target the virus directly, but rather work to cut off the hidden pathways it uses to spread and trigger inflammation.
Researchers hope this new approach will improve the treatment of severe cases of COVID-19 and enhance the world's preparedness to face future viral pandemics more effectively.
