Increased Expression of Aryl Hydrocarbon Receptor in Peripheral Blood Mononuclear Cells of Patients with Autoimmune Hepatitis

BACKGROUND Previous studies have indicated an elevated level of serum Interleukin (IL)-22 in patients with autoimmune hepatitis (AIH). However, there are no experimental data on the master transcription factor (aryl hydrocarbon receptor) that plays an important role in the development of T helper type 22 (Th22) cells as major producers of IL-22. The aim of the present study was to examine the expression of aryl hydrocarbon receptor in patients with AIH and in normal controls. METHODS Levels of mRNA transcripts were measured in the peripheral blood mononuclear cells of 18 patients with AIH and compared with 18 normal controls by a quantitative real-time polymerase chain reaction. RESULTS mRNA expression of aryl hydrocarbon receptor was significantly higher in patients with AIH compared with the healthy control group (P = 0.006). CONCLUSION Th22 cells may play an important role in the pathogenesis of AIH.