Researchers at Columbia University Irving Medical Center conducted a candidate-driven genetic association study of severe SARS-CoV-2 disease and identified that the complement system is related to infection severity. Specifically, they identified that patients with age-related macular degeneration are at greater risk of developing complications that result in death. Their results were published today in Nature Medicine.
The connection between the complement system and viral infection severity had been previously identified, "Viruses have proteins that can mimic certain host proteins to trick the host's cells into aiding the virus with completing its life cycle. Unchecked, these systems can also be quite detrimental," says study leader Sagi Shapira. "The new coronavirus—by mimicking complement or coagulation proteins—might drive both systems into a hyperactive state."
In order to find the relationship between the complement system and COVID-19 infection severity, the team took a closer look at the 11,000 patients that were treated for suspected COVID-19 at the research hospital. Through RNA-seq analysis, they found that 25% of those who suffered from macular degeneration died as a result of their infection.
"Together these results provide important insights into the pathophysiology of COVID-19 and paint a picture for the role of complement and coagulation pathways in determining clinical outcomes of patients infected with SARS-CoV-2," Shapira adds. "I think our findings provide a stronger foundation for the idea that coagulation and complement play a role in COVID-19.”