ObjectiveTo determine the nuclear factor kappa B (NFkB) activity in peripheral blood mononuclear cells (PBMC) in patients with acute cholangitis of severe type (ACST) and correlate the degree of NFkB activation with severity of biliary tract infection and clinical outcome.MethodsTwenty patients with ACST were divided into survivor group (14 cases) and nonsurvivor group (6 cases). Other 10 patients undergoing elective gastrectomy or inguinal hernia repair were selected as control group. Peripheral blood samples were taken 24 hours after operation, PBMC was separated and nuclear proteins were isolated from PBMC, and NFkB was determined with electrophoretic mobility shift assay (EMSA). The levels of TNFα, IL6 and IL10 in plasma were determined by using an enzymelinked immunoassay (ELISA). ResultsThe NFkB activity was 5.02±1.03, 2.98±0.51 and 1.02±0.34 respectively in three groups. It was increased in all patients with ACST, versus the control group (P<0.05), and the patients of nonsurvivor group had higher levels of NFkB activation than those of survivor group (P<0.05). The levels of TNFα and IL6 were (496.28±52.35) ng/L and (578.13±67.72) ng/L in nonsurvivor group; (284.47±39.41) ng/L and (318.67±34.92) ng/L in survivor group; (89.43±10.39) ng/L and (101.27±13.47) ng/L in control group. All patients with ACST had increased levels of TNFα and IL6, which were many fold greater than that of control group, and there was an evidence of significantly higher levels in nonsurvivor group than in survivor group (P<0.05). All patients had also increased levels of IL10 as compared to control group (P<0.05), but the IL10 concentrations in plasma were not significantly higher in nonsurvivors than that of in those survivors (Pgt;0.05). ConclusionNFkB activation in PBMCs in patients with ACST