In situ CD14 expression in biliary atresia: comparison between early and late stages.

PURPOSE: The aim of this study was to compare the in situ expression of CD14 between early and late stage of biliary atresia (BA) to determine if a time course of CD14 expression exists in BA. METHODS: Immunohistochemical analysis of membrane-bound CD14 expression was carried out in periodate-lysine-paraformaldehyde (PLP)-fixed frozen sections from 9 early- (obtained during Kasai procedure) and 6 late- (obtained during liver transplantation) stage cases of BA. Normal liver (n = 3) and choledochal cysts (n = 5) served as normal controls and disease controls respectively. RESULTS: In the early stage, 6 patients (66.66%) showed extensive CD14 expression (grade 3 [G(3)], more than 50% positive cells), whereas no CD14-positive cells could be detected in 4 patients (66.66%) in the late stage. In both stages, most of the positive cells were observed in the parenchyma of the hepatic lobules where Kupffer cells and sinusoidal endothelial cells stained positive. Arterial and venous endothelium, bile duct cells, and hepatocytes were negative for CD14. Double immunohistochemistry in the early stage showed a higher colocalization rate of CD14 and CD68 in the sinusoidal locations (33.69 +/- 9.270% [mean +/- SEM]) than in the portal tract (7.6+/-4.64% [mean +/- SEM]; P<.05). Similar pattern of colocalization also was observed in the late stage. In the normal controls no expression of CD14 could be detected, whereas in the disease controls only 1 case showed mild expression (grade 1 [G(1)], 1% to 10% positive cells) and the rest showed no expression of CD14. CONCLUSION: These results suggest that CD14 expression in BA is a dynamic phenomenon having time-related change with overexpression in the early stage and reduced expression in the late stage.