IL13 and asthma: PSCK6 has also been differentially expressed in bronchial brushings between cigarette smoking severe asthma and nonsmoking severe asthma111 and has been mentioned to be induced in vitro by interleukin (IL)‐4 and IL‐13, to activate NF‐κB, IL‐1, and IL‐6,25 to have a paracrine role in activating matrix metalloproteases30 and participate in glycoprotein metabolic process and endopeptidase inhibitor activity.