Interleukin-21 and tumor necrosis factor- are critical for the development of autoimmune gastritis in mice

Background and Aim Autoimmune gastritis (AIG), an organ-specific autoimmune disease, is accompanied by achlorhydria, pernicious anemia, gastric carcinoid tumors, and gastric cancer. Patients with AIG initially respond to corticosteroids but have a great potential to relapse after treatment is withdrawn. This study examines the roles of cytokines in order to identify potential therapeutic options for AIG patients. Methods Using a mouse model of AIG, we monitored disease progression and administered antibodies in vivo to block cytokines. Results We developed a mouse model of AIG with early onset and rapid progression in which neonatal thymectomy (NTx) was performed on programmed cell death 1-deficient (PD-1/) mice on the BALB/c background. Using NTxPD-1/ mice, we found that in AIG lesions, interferon-, and tumor necrosis factor (TNF)- together with interleukin-21 (IL-21) were highly expressed in the inflamed gastric mucosa. In addition, as with the injection of dexamethasone, in vivo administration of either anti-TNF- or anti-IL-21 suppressed the development of AIG in NTxPD-1/ mice. Conclusions These data reveal the essential role of IL-21 in the development of AIG and suggest that in addition to corticosteroids, anti-TNF- as well as anti-IL-21 have the potential to induce the remission of AIG, offering additional therapeutic options for AIG patients.