Student’s t-test was used to assess statistical significance. A value of p<0.05 was considered significant. Statistics were calculated with Prism version 5.0c (GraphPad). Funding support was from the National Institutes of Health (NIH) for WRB (K08 AI080952), SJS and TRH (R01 AI061464). The authors would like to acknowledge Malinka Jansson-Hutson and Destry Taylor for technical assistance. Conflict of interest: The authors declare no financial or commercial conflict of interest. "
“The importance of Ca2+ influx via store-operated calcium channels (SOCs) leading to mast cell degranulation is well known in
allergic disease. However, the underlying mechanisms are not fully understood. With food-allergic rat model, the morphology of degranulated mast cell was
analysed by toluidine blue stain and electron microscope. Ca2+ influx via SOCs was checked by Ca2+ imaging confocal microscope. Furthermore, the Lenvatinib in vivo mRNA and protein expression of NVP-BGJ398 SOCs subunits were investigated using qPCR and Western blot. We found that ovalbumin (OVA) challenge significantly increased the levels of Th2 cytokines and OVA-specific IgE in allergic animals. Parallel to mast cell activation, the levels of histamine in serum and supernatant of rat peritoneal lavage solution were remarkably increased after OVA treatment. Moreover, the Ca2+ entry through SOCs evoked by thapsigargin was increased in OVA-challenged group. The mRNA and protein expressions of SOC subunits, stromal interaction molecule 1 (STIM1) and Orail (calcium-release-activated calcium channel protein 1), were dramatically elevated under food-allergic condition. Administration of Ebselen, a scavenger of reactive oxygen species (ROS), significantly attenuated OVA sensitization-induced intracellular G protein-coupled receptor kinase Ca2+ rise and upregulation of SOCs subunit expressions. Intriguingly, pretreatment with PI3K-specific inhibitor (Wortmannin) partially abolished the production of ROS and subsequent
elevation of SOCs activity and their subunit expressions. Taken together, these results imply that enhancement of SOC-mediated Ca2+ influx induces mast cell activation, contributing to the pathogenesis of OVA-stimulated food allergy. PI3K-dependent ROS generation involves in modulating the activity of SOCs by increasing the expressions of their subunit. During the last two decades, a dramatic increase in the occurrence of food allergy has been reported in worldwide [1-3]. The prevalence of food allergy to milk, eggs and peanuts is reported to be around 6–8% of children under the age of three [4, 5], while it is less common in adult population with a percentage of about 4% . It has been documented that food allergy is primarily mediated by type I or Immunoglobulin E (IgE)-induced allergic reaction, although non-IgE-mediated allergy are gaining growing attention recently . The role of mast cell in the pathogenesis of food allergy is well established.