553:
Vitamin D Supplementation Attenuates Asthma Development Following Traffic-Related Particulate Matter Exposure
Sunday, March 4, 2018
South Hall A2 (Convention Center)
Paige E. Bolcas, B.S., Eric B. Brandt, PhD FAAAAI, Zhonghua Zhang, PhD, Jocelyn M. Biagini Myers, PhD, Brandy P. Ruff, B.S., Gurjit K. Khurana Hershey, MD PhD FAAAAI

RATIONALE: Children who are vitamin D deficient are uniquely susceptible to the effects of traffic-related air pollution (TRAP) exposure. Thus we hypothesized that vitamin D deficiency increases susceptibility to DEP exacerbated allergic asthma and this effect can be mitigated with Vitamin D supplementation.

METHODS: Using established mouse models of asthma, we examined the impact of pre-and post-natal vitamin D supplementation on asthma development as well as the utility of vitamin D as a treatment for established asthma in the context of diesel-exhaust particle (DEP) exposure.

RESULTS: DEP and allergen co-exposure resulted in increased airway hyperresponsiveness (AHR) and accumulation of pathogenic Th2/Th17 cells in the lungs of vitamin D deficient mice compared to control mice. Prenatal and postnatal vitamin D supplementation significantly attenuated the development of AHR, and decreased pulmonary accumulation of Th2/Th17 cells following co-exposure to TRAP and allergen, but not allergen alone. Restoration of normal vitamin D status had no impact on AHR once asthma was already established.

CONCLUSIONS: Our data establish that vitamin D confers protection against asthma development specifically in the context of TRAP exposure. While vitamin D replacement did not reverse established asthma, restoration of normal vitamin D status in early life significantly attenuated the development of AHR in DEP-exacerbated allergic asthma and reduced lung Th2/Th17 cells, which portend the development of severe asthma.