Vitamin D could reduce mold allergies
By Nathan Gray, 16-Aug-2010
Vitamin D may protect asthmatics from an allergic response linked to common mold, suggests a new study from the US supporting the vitamin’s immune health effects.
Results of a cell study ,published in the Journal of Clinical Investigation, identified a connection between vitamin D levels and the activity of certain allergy associated immune cells.
“We found that adding vitamin D not only substantially reduced the production of the protein driving an allergic response, but it also increased production of the proteins that promote tolerance,” said lead researcher Dr Jay Kolls from Louisiana State University Health Sciences Center.
Allergies – especially to common mould (Aspergillus fumigatus) can cause often severe complications for asthma sufferers, whilst also commonly effecting sufferers of cystic fibrosis.
The environmental mold is one of the most widespread fungal organisms inhaled by people, but does not cause any problems to the vast majority of people. However, in asthmatics and in patients with Cystic Fibrosis (CF), exposure can lead to significant allergic symptoms.
Up to 15 percent of CF patients have severe allergic responses – called Allergic Bronchopulmonary Aspergillosis (ABPA) – due to the inhilation of the common mold.
Kolls and colleagues set out to identify why only certain sub-set of patients with asthma and CF suffered from the mold allergy – assessing the factors that regulate the tolerance or sensitization to common mold during the development of ABPA.
The study found that the protein OX40L was critical in driving the allergic response to A. fumigatus. OX40L was found to increase the activity of Th2 cells, with a much greater Th2 response seen in immune cells isolated from patients with ABPA.
Immune cells from patients without ABPA were found to have higher levels of certain proteins that are essential in the development of allergen tolerance.
Vitamin D links
The research revealed high Th2 allergen reactivity in ABPA patients was associated with lower blood levels of vitamin D.
“We found that adding vitamin D not only substantially reduced the production of the protein driving an allergic response, but it also increased production of the proteins that promote tolerance,” said Dr. Kolls.
The study concludes that its data “strongly implicates vitamin D deficiency as a risk factor for ABPA”. Also suggesting that vitamin D enrichment or supplementation could be a valuable way to treat, and possibly prevent allergic reactions to common mold in people that are already suffering from respiratory conditions.
“Our study provides further evidence that vitamin D appears to be broadly associated with human health,” added 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.”
Kolls also said that the findings of the study “may be relevant to other allergies”.
He added: “Although there is no precise experimental data so show it, some the results with knockout mice suggest that vitamin D could play a role with other allergens.”
Source: Journal of Clinical Investigation
Published online ahead of print, doi:10.1172/JCI42388
“Immune tolerance to Aspergillus fumigatus versus Allergic Bronchopulmonary Aspergillosis: roles of OX40L and vitamin D in humans and mice.”
Authors: J.L. Kreindler, C. Steele, N. Nguyen, Y.R. Chan , et al.