IL5 and asthma: Not surprisingly, the underlying airway pathology of atopic versus nonatopic asthma is different, showing high numbers of eosinophils, T lymphocytes and Th2 cytokines (interleukin (IL)-4 and IL-5) in atopic asthma versus high numbers of neutrophils and non-Th2 cytokines (IL-8) in nonatopic asthma [3].