Regaining Heart Function With Transplanted Muscle Cells

A combination of cells and magnetic nanoparticles are injected into the damaged area of the heart after myocardial infarction that are held in place with tailored magnets which help the nanoparticle containing cells to engraft better to existing tissue, in a procedure which may lead to significant improvement in heart function.

As the name suggests cardiac tissue is a specialized muscle and the tissue is only located in the heart which immediately starts to beat as soon as formed. This is presents a challenge, as after a heart attack some cells in the tissue are damaged due to formation of clots that deprive them of oxygen and other nutrients in the blood. Repairing the damage is tricky as any replacement muscles are pushed out of the intended channel due to continuous pumping actions of the heart, with only a few cells attached to the cardiac tissue the amount of repair is limited.

In vivo studies were conducted on mice to determine efficacy of the procedure, in which mice that had previously suffered heart attacks were grafted with replacement muscles that were outfitted with magnetic nanoparticles. Animal subjects were divided into an experimental group which was also had a magnet placed a few millimeters from the surface of the heart; and a control group which only had the muscle graft. Animals in the magnet group were found to have had kept more transferred cells than those without magnets; and the experimental magnet group also retained 60% of the replacement cells settled in the target area, as compared to the control group that only had 25% of the replacement cells intact.

Effects of the magnetic field were immediate as the researchers observed cells under the magnetic field remaining at the target site 10 minutes after the procedure, and continued to do so on succeeding days until they were able to attach themselves to existing cardiac tissues. The transplanted cells did not die immediately, rather they were able to graft into cardiac tissue and multiply, which is suggested to possibly be due to more intensive cell-cell interaction between the transplanted cells and the tissues that translated into better cardiac function in the magnet group.

While this study has been successful in mice studies and has shown potential to possibly move into human treatment, clinical testing in humans requires further animal investigations, according to the researchers.

Previous studies have explored capabilities of nanomagnets repairing other parts of the body. The University of College London has also shown that nanomagnets could be used to deliver stem cells to injury sites improving the capacity of cells in repairing damaged tissues.