Two new studies on Hepatitis C (HCV) patients who underwent liver transplants examined a potential biomarker that could be used to predict who might develop hepatic fibrosis, a formation of scar-like tissue that can lead to cirrhosis. The studies found that changes in a certain type of liver cell were useful in determining those who were at the greatest risk for developing this serious complication.
The results of these studies appear in the October 2005 issue of Liver Transplantation, the official journal of the American Association for the Study of Liver Diseases (AASLD) and the International Liver Transplantation Society (ILTS). The journal is published on behalf of the societies by John Wiley & Sons, Inc. and is available online via Wiley InterScience.
Hepatitis C is the leading cause of liver transplants and recurrence of the disease following transplant is a serious problem. It is estimated that up to 20 percent of HCV patients will develop fibrosis or cirrhosis within two years of undergoing a transplant. Antiviral therapy is not highly effective in transplant patients and poses additional problems for these individuals, who may have difficulty tolerating the potent drugs it involves. However, antiviral therapy might be useful for those patients likely to develop fibrosis, if they could somehow be identified. Hepatic stellate cells (HSC) normally store vitamin A in the liver, but in HCV patients these cells produce collagen and other proteins that can lead to fibrosis. Researchers tried to determine if HSC activation could help predict which patients would later develop fibrosis by using laboratory analysis of alpha smooth muscle actin (alpha-SMA), a reliable marker for HSC activation.
In one study, led by Samer Gawrieh of the Division of Gastroenterology and Hepatology at the Mayo Clinic College of Medicine in Rochester, MN, 26 patients who underwent HCV-related liver transplants at the Mayo Clinic between April 1993 and July 1999 were included. Biopsies obtained 4 months and 1 year post-transplant were evaluated and given a score for alpha-SMA. The results showed that HSC activation of one particular type of cell (mesenchymal cells, which give rise to connective tissue) was highly reliable in predicting the development of fibrosis. "Staining early post-LT liver biopsies for alpha-SMA may help identify patients with hepatitis C at risk for severe recurrence who may benefit from early anti-HCV or anti-fibrotic therapy," the authors conclude.