American researchers have found that Vitamin D may treat or prevent allergy to a common mold that complicates asthma and cystic fibrosis.

Dr. Jay Kolls, professor and chair of Genetics at the Louisiana State University's Health Sciences Center New Orleans, led the study on how the environmental mold Aspergillus fumigatus causes severe allergic response called Allergic Bronchopulmonary Aspergillosis (ABPA) in asthma and CF patients. They also studied how some patients develop resistance to the mold.

In the study, two groups of patients were exposed to the mold with one group having ABPA.

The researchers found that a protein called OX40L causes cells that produce allergic response to react to A. fumigatus in patients with ABPA. The group of patients with ABPA also had much greater response to the mold and had lower Vitamin D in the blood.

In the group without ABPA, the patients' allergy response cells have higher levels of the proteins, FoxP3 and TGF-ß, which are critical to developing allergen tolerance.

When the researchers gave Vitamin D to the patients with ABPA, the production of proteins driving the allergic response was substantially reduced and the production of proteins that promotes tolerance increased, according to Kolls.

The next step in our research is to conduct a clinical trial to see if vitamin D can be used to treat or prevent this complication of asthma and Cystic Fibrosis, quoted Kolls as saying.