Dr. Tara Sander presented the study results on April 4 at Experimental Biology 2006 in San Francisco. Dr. Denise Klinkner, a surgical research fellow in Dr. Tara Sander's laboratory, conducted the study as part of ongoing research in Dr. Sander's laboratory to understand if abnormally high levels of endothelium-derived microparticles negatively affect the endothelial cells lining the heart valve leaflets, cells that are essential for normal function and repair and that often are injured or become dysfunctional in valve disease.
Dr. Sander's presentation was part of the scientific program of the American Society for Investigative Pathology. In the study, endothelial cells from the mitral valve tissue of a heart of an infant who received a heart transplant were exposed to increasing levels of endothelial-derived microparticles. At lower levels, comparable to those in nondisease states, the particles stimulated growth of the mitral valve endothelial cells, which is good. But at higher levels, equivalent to those seen in disease, the same particles inhibited the growth of these same cells. They also interfered with the cells' ability to respond to growth factors, indicating a disruption of normal pathways that control growth and migration of endothelial cells.
Interestingly, endothelial cells from other parts of the body responded differently to the different levels of microparticles. For ex
Contact: Toranj Marphetia
Medical College of Wisconsin