Jan. 26, 2011
A team of researchers in California and in Egypt report therapeutic benefit treating end-stage liver disease patients with adult stem cells A total of 48 patients were treated with their own adult stem cells--36 patients with chronic, end-stage hepatitis C-induced liver disease, and 12 patients with end-stage autoimmune liver disease. Researchers used the factor G-CSF, commonly used to mobilize bone marrow adult stem cells into the circulation, to obtain the cells from each patient. The CD34+ stem cells were then isolated, amplified to increase numbers of cells, partially differentiated in culture, then re-injected into each patient via their hepatic artery or portal vein. The results were published in Cell Transplantation
According to co-author Dr. Mark A. Zern of University of California-Davis Medical Center:
"This enabled us to transplant as many as one billion of these cells per patient. For all patients there was a statistically significant decrease in peritoneal cavity fluid, or 'ascites'. There was also clinical and biochemical improvement in a large percentage of patients who received the transplantation. The finding of improvement in ascites in a significant number of patients is impressive and somewhat surprising, suggesting that cell transplantation might be clinically significant beyond the improvement in laboratory parameters."
The mechanism by which the infusion of CD34+ adult stem cells improves liver function is still unclear. As to whether any partial differentiation into liver cells was needed for the therapeutic results, Dr. Stephen Strom at the University of Pittsburgh and section editor for Cell Transplantation, noted:
"Other research groups are now showing similar results with cells without any hepatic characteristics, including fractionated and unfractionated bone marrow and mesenchymal stem cells. Taken together, these data suggest that the positive effects these researchers find may be the result of paracrine effects from factors secreted by the donor cells.
Published data in 1999 suggested that some bone marrow adult stem cells could form liver hepatocytes. Others reported similar results in 2000 using mice, by observing liver cells of human bone marrow adult stem cell transplant patients, and in experiments showing regeneration of liver in mice. However, some published evidence also indicates that the regenerative capacity of bone marrow adult stem cells is due to paracrine effects, i.e., secreted factors.
No matter what the mechanism, various clinical trials are investigating use of adult stem cells for liver diseases. Published results from earlier trials show therapeutic benefit of adult stem cells for liver repair and regeneration.
In a published 2010 report, a Korean group found some improvement in liver cirrhosis patients using their own adult stem cells.
In 2006 a U.K. group reported improvement in patients with liver insufficiency treated with their own adult stem cells, and the same group reported in 2008 the long-term improvement of chronic liver disease patients, using the patients' own adult stem cells in a trial similar to the current Egyptian trial.
Also in 2006, a German group reported increased liver regeneration in liver cancer patients using adult stem cells, and a Japanese team found improved liver function in cirrhosis patients after using the patients' own bone marrow adult stem cells.
Adult stem cells continue to provide ethical and successful results for patients.