Oral administration of TLR9 agonists displayed a significant benefit in the treatment of asthma and food allergy in mice.38 Several kinds of TLR agonists have now been applied to asthmatic or allergic patients in clinical trials.37, 39 In the case of TLR9 agonists, CpG‐containing nucleotides (Amb a 1‐CpG vaccine)40, 41 and bacteriophage‐derived virion‐like particles (VLPs) packaging A‐type CpG motif42 have been shown to be effective in treating rhinitis and allergic asthma. Here, TLR9 is linked to allergic asthma.