Cardiac muscle regeneration using mesenchymal stem cells

Patent Number: 6387369

This patent covers the use of mesenchymal stem cells for cardiac repair, specifically after myocardial infarction. Mesenchymal stem cells are currently in clinical trials for this application. In fact the same company to which this patent is assigned to, Osiris Therapeutics, has actually published positive double blind data on patients post infarct treated with allogeneic, intravenously administered mesenchymal stem cells.

It is not clear if the effect is through secretion of growth factors by the mesenchymal stem cells that stimulate endogenous cardiac stem cells to proliferation and/or differentiate, or if the mesenchymal stem cell itself is transdifferentiating into cardiomyocytes. In any case, to date it appears that the mesenchymal stem cells do not cause asynchrony in the heart electrical pathways, which is always a concern with this type of cell therapy.

The patent has two independent claims. The first covers "a process" for making heart muscle cells by administration of mesenchymal stem cells, with the mesenchymal stem cells differentiating into cardiac muscle cells. The second also covers "a process", but this time the process is to reduce scar formation by administration of mesenchymal stem cells.

The dependent claims cover, intra alia, systemic administration, injection, injection into the heart, and human mesenchymal stem cells.

There are 2 examples described in the patent, the first shows that injection of human mesenchymal stem cells into the myocardium of an immune compromised rat (athymic rat) and demonstration that the injected cells acquired a myocardium-like phenotype. The second example was the "seeding" of a bioartificial heart valve with mesenchymal stem cells and demonstration that the valve was capable of function.

View this patent on the USPTO website.