Similarly to asthma, mast cells, Th2 cells, basophils, and epithelial cells synthesize and release cytokines and chemokines (IL-3, IL-4, IL-5, IL-10, IL-13, GM-CSF, and RANTES), which are responsible for sustaining allergic inflammation and the associated oxidative/nitrosative stress (115). The gene discussed is IL4; the disease is asthma.