Source: Duke University
Date: October 12, 2009
Summary:
DURHAM, N.C. -- By mimicking the way embryonic stem cells develop into heart muscle in a lab, Duke University bioengineers believe they have taken an important first step toward growing a living “heart patch” to repair heart tissue damaged by disease.
In a series of experiments using mouse embryonic stem cells, the bioengineers used a novel mold of their own design to fashion a three-dimensional “patch” made up of heart muscle cells, known as cardiomyocytes. The new tissue exhibited the two most important attributes of heart muscle cells -– the ability to contract and to conduct electrical impulses. The mold looks much like a piece of Chex cereal in which researchers varied the shape and length of the pores to control the direction and orientation of the growing cells.
The researchers grew the cells in an environment much like that found in natural tissues. They encapsulated the cells within a gel composed of the blood-clotting protein fibrin, which provided mechanical support to the cells, allowing them to form a three-dimensional structure. They also found that the cardiomyocytes flourished only in the presence of a class of “helper” cells known as cardiac fibroblasts, which comprise as much as 60 percent of all cells present in a human heart.
