Research Reveals Cystic Fibrosis Severity Is Linked to Fungus

According to recent findings, cystic fibrosis (CF) severity may be associated with the immune system’s overreaction to a specific type of fungus – Aspergillus fumigatus.

Researchers based in the UK have found that in patients with CF, types of white blood cells that ingest and kill invading organisms, known as phagocytes, give off higher concentrations of harmful reactive oxygen species as a defense mechanism against the fungus. The study supports the notion that Aspergillus fumigatus may play a vital role in triggering lung infection in patients with CF.

Aspergillus fumigatus colonization in CF

About 58% of patients with CF are colonized with Aspergillus fumigatus and an estimated 47.7% of adult patients are affected by allergic reactions or an infection triggered by the fungus. Persistent infections are also known to be associated with lower lung function and increased hospitalization rates among patients with CF.

The researchers involved in the study compared the immune response of phagocytes from patients with CF with those of healthy individuals. In order to address the anti-fungal properties of the phagocytes, these white blood cells were isolated from the blood of patients with CF and healthy donors. The researchers purified various segments of the phagocytes, separating the most prominent ones - monocytes and neutrophils.

In general, while the researchers saw that the phagocytes were equally effective in ingesting and killing fungus cells in both groups, they noticed that the phagocytes from the patients with CF behaved differently at the release of reactive oxygen species. Such species have the potential to cause cell damage and eventually lead to cell death. The researchers found that all segments of the phagocytes gathered from the patients with CF produced higher concentrations of reactive oxygen species in the presence of Aspergillus fumigatus. The worse a patient’s lung function was, the higher the release of reactive oxygen species from the patient’s phagocytes. “Our data suggest that a hyper responsive state in CF phagocytes plays a crucial role in the hyperinflammatory response upon exposure to A. fumigatus,” wrote the researchers. “New interventions to prevent fungal induced ROS production need to be explored, such as early treatment of Aspergillus infection or targeting the defective molecular pathway underlying these aberrant responses,” they concluded.

Read on to learn more about these important findings and what it all means for the future of cystic fibrosis management and treatment.