Researchers link intestinal fungi to immune disruption in severe COVID-19
Researchers from the Cornell University Graduate School have identified a link between the coronavirus and immune system disturbances that involve inflammatory fungi in the human gut. The findings, published in Nature, add a new layer to how the immune response behaves in serious cases of COVID-19.
The study focused on patients who were severely ill with COVID-19. Blood samples were analyzed, and detailed health information was collected to understand the immune dynamics at play during the infection.
Laboratory work revealed that certain patients showed immune imbalances. The researchers traced these imbalances to Candida albicans, a yeast that can inhabit the intestines. The presence of this fungus is associated with weakened immune responses and can contribute to lung injury. Notably, antibodies targeting Candida albicans appeared in the blood of patients, persisting for up to a year after recovery. These antibodies correlate with a protein called IL-6, which tends to rise during inflammatory states and appears to sustain the immune signal after infection ends.
To suppress the inflammatory activity of Candida albicans and mitigate its downstream effects on the lungs and immune system, participants received antifungal therapy. The treatment demonstrated an ability to dampen IL-6 receptor activity and lower inflammatory markers, offering a potential pathway to reduce lung damage in severe COVID-19 cases.
The researchers concluded that persistent inflammation driven by intestinal fungi may contribute to the persistence and severity of COVID-19 symptoms. Recognizing this link could inform the development of new therapeutic strategies that focus on the gut microbiome and its relationship with immune signaling networks.
Prior work has explored how severe mental illness can influence outcomes in COVID-19, highlighting the broad impact of the virus on health and the value of understanding diverse biological pathways in patient care.
Attribution: This summary reflects findings reported from the Cornell University Graduate School and peer-reviewed in Nature, with interpretations drawn from the published study and subsequent expert reviews.