Yanagawa et al. reported that Toll-like receptors (TLR)2 or TLR4-positive basophils infiltrated into the pancreas of patients with type 1 AIP and that the ratios of basophils activated by TLR4 stimulation in type 1 AIP and atopic dermatitis were significantly higher than those in healthy subjects [43]. Here, TLR4 is linked to autoimmune pancreatitis type 1.