Gene expression of interleukin-12 receptor β2 chain and Th1 population of peripheral blood mononuclear cells in chronic hepatitis C

Gene expression of interleukin 12-receptor β2 chain mRNA in peripheral blood mononuclear cells (PBMCs) was examined in patients with chronic hepatitis C (n = 7) and in healthy control subjects (n = 6) by semi-quantitative RT-PCR. The level of interleukin 12-receptor β2 chain mRNA was higher in patients with chronic hepatitis C than in healthy subjects (P = 0.032). The level of interleukin 12-receptor β2 chain mRNA had a weak correlation with the ratio of Th1 to Th2 populations (r = 0.714, P = 0.020). There was a tendency for the level of interleukin 12-receptor β2 mRNA to increase both in chronic hepatitis C (P = 0.109) and in healthy volunteers (P = 0.144) after the incubation of PBMCs with interferon-α in vitro. During interferon-α administration to the patients with chronic hepatitis C, the level of interleukin 12-receptor β2 chain mRNA in PBMCs was increased in all four cases. Although this is a preliminary study with a small sample size, our results suggest that the level of interleukin 12-receptor β2 chain mRNA is higher than normal in patients with chronic hepatitis C and can be further enhanced by interferon therapy.