Link between vitamin D and IL33 and sST2 in children with asthma

It9s now admitted that vitamin D deficiency is associated with allergic diseases and asthma. Recently, IL33, an IL1 family cytokine was described as an “alarmin” that promotes TH2-type cytokines and airway inflammation in asthma. Recent data showed a possible interaction between IL33 and vitamin D levels when vitamin D supplementation increased sST2 levels a soluble IL33 receptor and inhibitor in situ of IL33. The aim of our study was to investigate the link between serum levels of IL33 and vitamin D (by ELISA) according to disease severity and control in winter and summer in 38 asthmatic children (17 mild asthmatics and 21 moderate asthmatics) compared to 30 healthy controls (HC). Our results showed that vitamin D levels were lower in asthmatics compared to HC in summer (p=0.004). These levels were lower in winter and in more severe asthma (p These results suggest that vitamin D deficiency may increase IL33 levels and thus induce TH2 inflammation. Vitamin D supplementation may reduce inflammation through sST2 production.