Cytokine profile in the liver of primary biliary cirrhosis.

We characterized the cytokine profile in the liver of patients with primary biliary cirrhosis (PBC). Total RNA was extracted from the biopsy specimens of 9 patients with early-stage PBC, 10 with chronic hepatitis C (CHC), and 4 normal controls. cDNA was prepared and amplified with a polymerase chain reaction using primers for interferon (IFN)-γ and interleukin (IL)-2, -4, -5, -6, -10, -12 (p40), and -15. Cytokines such as IFN-γ and IL-5, -6, -10, -12, and -15 were expressed in most cases of PBC. Expression rates of IL-5 and IL-6 were higher than in CHC and controls. The higher expression rate of IL-5 in PBC was associated with eosinophil infiltration. IL-2 and IL-4 were rarely detected. Semiquantitative analysis revealed that the expression of IFN-γ and IL-10 was reversed in PBC and CHC: high IFN-γ and low IL-10 in PBC and high IL-10 and low IFN-γ in CHC. These results suggest that cytokine expression is skewed in PBC and both Th1 and Th2 cytokines may play a role in the pathogenesis.