SOLUBLE ICAM-1 (SICAM-1) IN BILIARY ATRESIA AND ITS RELATIONSHIP TO DISEASE-ACTIVITY

Background. Intercellular adhesion molecule-1 (ICAM-1) is strongly exp ressed on the bile ducts and hepatic parenchyma of livers with biliary atresia. A soluble, circulating form of this membrane protein has bee n found to be elevated in a number of inflammatory hepatic disorders. However, its expression in biliary atresia is unknown. The purpose of this study was to assess the presence of soluble ICAM-1 in infants wit h biliary atresia in relation to disease activity, degree of cholestas is, and standard liver function tests. Materials and methods. A total of nine patients (n = 9) with biliary atresia (seven) and neonatal hyp erbilirubinemia (two) were studied (age range 6 weeks-9 years). Contro l samples were obtained from three healthy infants (2-10 months). Seru m was collected from each patient and stored at -80 degrees C until as sayed. Levels of sICAM-1 were measured in duplicate utilizing an ELISA method (Bioscource International). Standard liver function tests (con jugated bilirubin, gamma-glutamyl transpeptidase, alkaline phosphatase , alanine aminotransferase) were determined at the same time. Results are expressed as the means +/- SEM with statistical analysis by Mann-W hitney test. Results. sICAM-1 levels were significantly elevated in al l patients with biliary atresia (997 +/- 56 ng/ml) when compared to co ntrols (P < 0.001). No correlation was found between sICAM-1 levels an d conjugated bilirubin, gamma-glutamyl transpeptidase, alkaline phosph atase, and alanine aminotransferase levels or with clinical assessment of disease severity. Conclusions. sICAM-1 is markedly elevated in bil iary atresia reflecting the immunopathology of the disease process but does not appear to correlate with markers of liver function, sICAM-1 may be useful in assessing the effects of immunomodulatory therapy. (C ) 1998 Academic Press.