EGF and asthma: The anti-apoptotic activity also showed an increasing trend with asthma severity (linear contrast tests, basal-CM p = 0.046 and EGF-CM p = 0.009) (Figure 2B), as observed previously with airway epithelial lining fluid (sampled by sputum induction) from severe asthmatics [4], but there was no additional EGF-induced effect when compared to anti-apoptotic responses mediated by unstimulated PBECs (Table S1).