03/12/07
A new study involving a type of stem cells from the lungs of transplant patients demonstrates for the first time that these progenitor cells reside in adult organs and are not derived from bone marrow, which leads to the possibility that the cells may be able to help with the rejection of donated organs and with various kinds of lung disease.
The study appears online March 8 in advance of publication in the April print issue of the Journal of Clinical Investigation. The findings by University of Michigan Health System researchers are significant because of the large number of lung transplant patients who experience chronic rejection of donated lungs, with rejection rates of about 60% during the first five years after transplantation.
The researchers studied mesenchymal stem cells (MSCs), a type of progenitor cell that most commonly originates in the bone marrow. MSCs are widely seen as a potential source of therapies for numerous diseases and conditions, such as cystic fibrosis. In this study, lead author Vibha N. Lama, MD, MS, and her research team found that the MSCs in lung transplant patients are not derived from bone marrow, but rather that they reside—sometimes for many years—in the lungs. The researchers also found that these cells have the capacity to differentiate into multiple connective tissue cell types.
“Potentially the most important outcome of our finding is that it could lead to an understanding about therapeutic options using MSCs that reside in adult organs,” said Lama. “These lung-derived cells are different from MSCs derived from bone marrow in the expression of various genes, which makes us believe that they are specific to the organ they are isolated from.”
Lama’s laboratory is currently working on another study involving the lung-derived MSCs that shows potential importance of these cells in lung transplantation. That study is not yet complete, but so far it indicates a very strong ability of these MSCs to suppress the immune cells that are involved in organ rejection.
