IL4 and asthma: Type II inflammatory asthma involves T helper type 2 cells, ILC2, T follicular helper cells, eosinophils, mast cells, and type II mediators, such as cytokines IL‐4, IL‐5, IL‐13, and prostaglandin D2, etc.9, 106, 107, 108In fact, different types of gut microbiota affect asthma via the gut‐lung axis with different pathological changes.