HBEGF and asthma: IL‐13 plays an important role in epithelial repair via heparin binding epidermal growth factor (HB‐EGF) 26 and IL‐13 expression has been shown to closely mirror epithelial HBEGF expression in a sub cluster of severe asthma patients with evidence of neutrophilic inflammation from the U‐BIOPRED cohort.27