The study by University of Michigan Health System researchers is significant because of the large number of lung transplant patients who experience chronic rejection of donated lungs, with rejection rates of about 60 percent 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. In this study, lead author Vibha N. Lama, M.D., M.S., 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.
One of the most telling findings was that, in cases where the transplant donor and recipient were not of the same sex, nearly all the MSCs (about 97 percent) originated in the donor, indicating that they were present in the tissue since the time of transplantation. "We were able to isolate the cells derived from the donor as far as 11,5 years after transplantation," says Lama, assistant professor in the Division of Pulmonary and Critical Care Medicine at the U-M Medical School. "We discovered the existence of a population of MSCs that reside and self-renew in the tissues of the adult lung ?something that might hold true for other organ systems as well.
"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," Lama continues. "These lung-derived
Source:University of Michigan Health System