Researchers have found that vitamin D may be an effective therapy to treat and even prevent allergy to a common mold that can cause severe complications for patients with cystic fibrosis and asthma. The findings are published in the Journal of Clinical Investigation.
Aspergillus fumigatus is one of the most common airborne molds, and while it does not cause illness in the vast majority of those who inhale it, it can cause life threatening allergic symptoms in patients with cystic fibrosis. As many as 15% of patients with cystic fibrosis will develop a severe allergic response, known as Allergic Bronchopulmonary Aspergillosis (ABPA). Some patients with asthma can also develop ABPA.
The researchers studied cystic fibrosis patients who had A. fumigatus infections. One group had developed ABPA, while the other had not. The researchers found that the ABPA patients had a heightened response by immune cells known as type 2 T helper (Th2) cells, and that a protein known as OX40L was critical to this heightened response. The heightened Th2 response correlated with lower levels of vitamin D as compared with the non-ABPA patients. Adding vitamin D to these cells in the laboratory substantially reduced the expression of OX40L and increased the expression of other proteins critical to the development of allergen tolerance.
“Based on our results, we have strong rationale for a clinical trial of vitamin D to determine whether it can prevent or treat ABPA in patients with cystic fibrosis,” said Jay Kolls, MD, PhD, professor of pediatrics at the University of Pittsburgh School of Medicine, and professor and chair of genetics at Louisiana State University Health Sciences Center in New Orleans.