One of the most difficult muscles to repair are those that make up the heart. Now scientists working at the Worcester Polytechnic Institute in Massachusetts believe they’ve found a method that’s so simple it’s stunning other medical researchers.
The team seeded the microthreads with mesenchymal stem cells. The hope is the cells will heal damaged muscle tissue as the treated thread is used in sutures.
The revolutionary approach was created by Glenn Gaudette and his team. The sutures—fibrin microthreads the thickness of human hairs—are made of a standard polymer protein. The surures have been used in surguries and tissue bioengineering for a number of years.
Charles Murry, a director of the Center for Cardiovascular Biology at the University of Washington told technologyreview.com that “This is an out-of-the-box approach. Putting cells on thread—once you hear it, it seems simple. But I’ve been in this field for 15 years, and I never thought of it.”
While Murry was not involved in the study, he is a leading researcher in the field.
Currently, the Worcester Polytechnic team are analyzing the stem cell-suture approach. They’re determining the duration of time the cells remain at the site of an injury. The big question is, will the theory pan out? Will the seeded sutures assist in significantly repairing the damaged tissue?
Although the preliminary results are promising, a larger question remains: can this new technology be expanded to seed the stem cells needed to repair the muscles of the heart wall? Depending upon the amount of damage, hundreds of millions of cells may be required.
The current process the team has developed entails transferring the micro strands into a tube of growth solution and stem cells. By gradually rotating the tube, the cells stick uniformly to the polymer thread. After the cells have been transferred (about 10,000 can be seeded onto one two-centimeter long group of threads. Once prepared, the newly seeded suture can be threaded onto a needle.
According to Gaudette, the size of the bundled threads can be varied and the rate at which the microthread disintegrates within the tissue can be controlled.
The director of the Institute for Molecular Cardiology at Stony Brook University in New York, Ira Cohen, collaborated with Gaudette on other research projects in the past. Although he did not collaborate on the seeding research, he shared his views concerning this new approach during an interview with technologyreview.com” “This new technique provides a wonderful tool for cell delivery for cardiac repair and for electrical problems as well, where you might want to create a new electrical path.”
The approach is gaining traction. Other research groups are using a similar technology to seed various types of cells to damaged body parts. Some research groups are looking at the possibilities inherent in seeding technology to repair cardiac myocytes that compose the heart’s striated muscle tissue, vascular cells and other types of cells that comprise the cardiovascular system.
Eventually, the researchers hope, damaged tissue may be repaired by introducing seeded sutures through a catheter in the vascular system to the area of damage. The process will then effect a quick and permanent repair.
