Expression of the mucosal vascular addressin, MAdCAM-1, in inflammatory liver disease.

Aims/Background: The integrin alpha 4 beta 7 and mucosal addressin cell adhesion molecule-1 (MAdCAM-1) are involved in normal recirculation of lymphocytes between the blood and the tissues of the gastrointestinal tract. In this study we have examined the expression of MAdCAM-1 in human liver. Methods. MAdCAM-1 expression was determined in archival human liver tissues by immunohistochemistry. Results: While MAdCAM-1 was not detected in normal fetal or adult human liver, expression was observed in association with portal tract inflammation in a variety of liver diseases. Detailed analysis of liver biopsies from patients with hepatitis C showed a positive correlation between the portal/periportal component of the histological activity index (HAI) grade and the presence or absence of MAdCAM-1 expression. Conclusion: MAdCAM-1 expression may be important in the recruitment of lymphocytes to the liver during inflammation.