A new study has enabled a detailed understanding of the formation of fibrotic cells, their manner of multiplication and finally their destruction of the human liver, leading to cirrhosis. In doing so, the findings by the researchers at the University of California, San Diego School of Medicine, and colleagues in Austria upend the standing of a long-presumed marker for multiple fibrotic diseases, and reveal the existence of a previously unknown kind of inflammatory white blood cell. In all types of chronic diseases, healthy, functioning tissues are progressively replaced by fibrous scarring, which render the tissues or larger organ increasingly dysfunctional until, eventually, it fails. The process is called fibrosis. In the human liver, the end result is cirrhosis. Scientists could not fully understand the process of fibrosis, particularly how problematic fibroblast cells are created. For years, conventional wisdom has posited that fibroblasts are likely to be transformed epithelial cells, a conversion called 'epithelial to mesenchymal transition' or EMT. A protein called fibroblast-specific protein 1 (FSP1) has long been considered to be a reliable indicator of fibroblasts in injured organs undergoing tissue remodeling and has been broadly used to identify the presence of fibrotic disease. The new research undermines the validity of prevailing assumptions about EMT and FSP1, but also opens the door to new avenues of investigation that could ultimately lead to improved detection and treatment of cirrhosis and similar conditions. "This work, along with earlier papers, puts into question a whole area of research - at least in terms of the liver," said David Brenner, dean of the UC San Diego School of Medicine and co-author of the paper. "The old evidence and assumptions about the source of fibroblasts and the role of FSP1 as a marker are not valid," he added. Specifically, in experiments using cell cultures, human liver samples and mouse models, the researchers found no evidence of EMT - that transformed epithelial cells became liver fibroblasts. Rather, endogenous stellate cells appear to be the culprit, though the scientists note many types of cells seem to contribute, directly or indirectly, to liver fibrosis. Likewise, experiments proved FSP1 to be an unreliable marker for fibrosis. Cells containing FSP1 increased in human and experimental liver disease and in liver cancer, but researchers found that liver fibroblasts do not express the protein, nor do hepatic stellate cells - a major cell type involved in liver fibrosis. Similarly, FSP1 was determined not to be a marker for myofibroblasts (a fibroblast with some properties of a smooth muscle cell) or any precursors of myofibroblasts. "There have been hundreds of papers based on FSP1 as a marker," said Brenner. "That thinking now seems to have been a mistake. One of the take-home messages of this paper is that FSP1 clearly can't be reliably used as a marker," he added. On the other hand, the scientists discovered that FSP1 is a consistent marker for a previously unknown subset of inflammatory white blood cells or macrophages found in injured livers. The protein appears to also perform biological functions in the macrophages, though these remain to be determined. "It's a whole new class of monocytes. We don't know what they do, but they're worth investigating," said Brenner. The results are published in this week's early online edition of the Proceedings of the National Academy of Sciences.Source: ANI << Do Away With Diet Bars and Shakes as a First Step for Weigh... The Most Searched for Term in 2010- 'Austerity' >> Recommended Reading Alcoholic Liver Disease Encyclopedia section of medindia gives general information about Alcoholic Liver Disease. READ MORE Genetic Variation Associated With Liver Cirrhosis in Alcoholic Caucasians - Study German researchers in a study pointed that variation in PNPLA3 (adiponutrin) gene is associated with liver cirrhosis and high levels of transaminase (liver enzyme)in alcoholic caucasians. READ MORE Liver Disease- 12th Most Common Cause Of Deaths in US: Study Statistics from the Centers for Disease Control and Prevention (CDC) rank mortality related to chronic liver disease and cirrhosis as the 12th most common cause of death in adults in the U.S. READ MORE Clinical Trials Start on Potent New Hepatitis C Drug Scientists have launched the first clinical trials on a new investigational drug. READ MORE Current Treatments for Liver Cancer Current Treatments for Liver Cancer (also known as hepatoma or hepatocellular carcinoma) can result in complete cure of the disease if it is detected early. READ MORE Fatty Liver Disease: A Growing Health Problem in India Non alcoholic fatty liver disease (NAFLD) is the leading cause of liver dysfunction worldwide and is a rapidly growing health problem in India. READ MORE Hepatitis A Hepatitis A is the most benign of the hepatitis viruses and usually has no long term side effects. Hepatitis A vaccine is available that is 95% effective in preventing the disease. READ MORE Living Donor Liver Transplant: What Are the Risks? The risk of dying as a result of a living donor liver segment removal is between 0.2-2.0%. The risk of morbidity is anywhere between 1.3% (in highly experienced centers) to 60%. READ MORE Milk Thistle Milk Thistle is a resourceful natural plant which has many medicinal benefits. In herbal medication milk thistle is used in cases of liver diseases. READ MORE Wilson's Disease This is a rare inherited systemic disorder of copper metabolism, affecting the liver mainly before other organs. READ MORE Most Popular on Medindia How to Reduce School Bag Weight - Simple Tips Blood Pressure Calculator Daily Calorie Requirements More News on: Alcoholic Liver DiseaseLiver BiopsyHepatitis ALiverWilson's DiseaseMilk ThistleCurrent Treatments for Liver CancerFatty Liver Disease: A Growing Health Problem in IndiaLiving Donor Liver Transplant: What Are the Risks?