ELISA analysis revealed that antibodies to prohibitin is present in 73.5% (25/34) of patients with definite AIP, 53.3% (8/15) of patients with Mikulicz’s disease, 54.5% (6/11) of patients with retroperitoneal fibrosis, and 89.7% (26/29) of patients with other probable IgG4-RD but in only 1.4% (1/70) of healthy donors [24]. Here, PHB1 is linked to IgG4-related retroperitoneal fibrosis.