According to University of Sheffield
Researchers at the University of Sheffield have uncovered a previously unknown mechanism that allows pathogenic fungi to evade the human immune system, offering new insights that could support the development of future antifungal therapies. The study, conducted at Sheffield’s Bateson Centre for Disease Mechanisms and published in mBio, reveals how disease-causing fungi effectively “blind” immune cells by masking key components of their cell walls, preventing early recognition and delaying the body’s defensive response. Scientists believe the findings could help address one of the most urgent global health challenges—the growing threat of antifungal resistance and the limited number of effective treatments available for life-threatening fungal infections.
The human immune system normally identifies fungal pathogens by recognizing molecules within the fungal cell wall, particularly β-glucan, which acts as a molecular signature detected by immune receptors such as Dectin-1. However, the research demonstrates that pathogenic fungi can reorganize or conceal these cell-wall structures beneath an outer protective layer, significantly reducing immune recognition. Specifically, the Sheffield team found that Candida actively suppresses production of reactive nitrogen species (RNS) — toxic molecules normally used by neutrophils, the body’s most abundant white blood cell, to kill invading microbes — reducing these protective molecules to levels below normal baseline activity. As a result, immune cells fail to detect the invading fungus efficiently during the earliest stages of infection, providing the pathogen with valuable time to establish itself within host tissues. Researchers describe this immune evasion strategy as one of the key factors contributing to the success of opportunistic fungal pathogens, especially in individuals with weakened immune systems. Notably, an estimated 40 to 60 percent of healthy people carry Candida albicans harmlessly, yet in people with weakened immune systems it can enter the bloodstream and trigger invasive candidiasis, a condition with mortality rates approaching 50 percent.
The discovery has important implications for the treatment of invasive fungal diseases caused by pathogens such as Candida, Aspergillus, and other opportunistic fungi. Current antifungal therapies primarily target fungal growth or cell membrane synthesis, yet increasing resistance has reduced treatment effectiveness in several medically important species. The study found that similar immune suppression was observed in other clinically important fungal pathogens, including the emerging multidrug-resistant species Candida auris. By understanding the molecular mechanisms responsible for immune masking, researchers hope to develop therapies that expose hidden fungal cell-wall components, allowing the immune system to recognize infections more rapidly and improving the effectiveness of existing antifungal drugs. Rather than killing fungi directly, future treatments may strengthen the body’s own immune response by preventing pathogens from remaining concealed.
Health experts note that invasive fungal infections remain a major cause of illness and death among patients undergoing chemotherapy, organ transplantation, intensive care, or immunosuppressive therapy. The World Health Organization has identified several fungal pathogens as priority threats because of rising antifungal resistance and the limited pipeline of new medications — including designating both C. albicans and C. auris as critical priority pathogens. Researchers emphasize that the Sheffield findings remain at the experimental stage, and additional studies will be required before new immune-targeting therapies become available for clinical use; the team is now working to identify the exact molecular pathways Candida uses to disable neutrophils and to investigate whether RNS-targeting therapies could safely progress to human clinical trials. Nevertheless, the work represents an important advance in understanding fungal pathogenesis and may contribute to future strategies that combine antifungal medicines with immune-enhancing approaches to improve outcomes for vulnerable patients facing life-threatening fungal infections.
References
Mirage News (2026). Scientists Uncover How Fungi ‘blind’ Immune System.
According to University of Sheffield
