The MFI of BAFF-R decreased with stimulation of rhBAFF (from 554.80 ± 230.2 to 166.8 ± 92.66; P <0.01; Figure 2G-H), indicating that expression of BAFF-R might be inhibited by chronic BAFF overproduction in IgG4-RD patients. The gene discussed is TNFRSF13C; the disease is immunoglobulin G4-related sclerosing disease.