A new study on the ability of liver cells to interact with T cells (lymph cells that play a role in regulating the immune response) found that such interactions do occur and demonstrated the mechanism by which they may take place. The results may help explain the altered immune responses that occur with aging and other conditions and may be useful in developing therapies for viral hepatitis and autoimmune diseases.

The results of this study appear in the November 2006 issue of Hepatology, the official journal of the American Association for the Study of Liver Diseases (AASLD). Published by John Wiley & Sons, Inc., Hepatology is available online via Wiley InterScience at http://www.interscience.wiley.com/journal/hepatology.

The liver possesses an unusual ability to stimulate immune tolerance, possibly due to its distinctive architecture that allows T cells normally activated in the lymph system to become activated by liver cells. Normally, endothelial cells that line blood vessels form a physical barrier that prevents nave (unactivated) T cells from accessing surrounding tissue; these cells must typically be activated by specialized cells known as professional antigen presenting cells (APCs) before they are able to migrate across the endothelium and interact with organ cells. Recent studies have shown that the liver is an exception in that liver cells may be able to act as APCs, activating T cells independently of the lymph system, a process which makes them less efficient. However, the question remains as to how T cells can cross the endothelial barrier to interact with liver cells.

A collaborative work between Alessandra Warren and David Le Couteur of the Centre for Education and Research on Ageing (CERA), Concord RG Hospital and Patrick Bertolino of the Centenary Institute, University of Sydney, Australia, has led to the first study investigating the interactions
'"/>

Contact: David Greenberg
dgreenbe@wiley.com
201-748-6484
John Wiley & Sons, Inc.
1-Nov-2006