Cheap, abundant cardiomyocytes

A team of Wisconsin scientists has found a way to transform human stem cells - both embryonic and induced pluripotent stem cells - into the critical heart muscle cells by simple manipulation of one key developmental pathway. Outlined in the Proceedings of the National Academy of Sciences, the technique promises a uniform, inexpensive and far more efficient alternative to the complex bath of serum or growth factors now used to nudge blank slate stem cells to become specialised heart cells.

The ability to make the key heart cells in abundance and in a precisely defined way is important because it shows the potential to make the production of large, uniform batches of cardiomyocytes routine. The cells are in great demand for research, and increasingly for the high-throughput screens used by the pharmaceutical industry to test drugs and potential drugs for toxic effects.

The capacity to make the heart cells using induced pluripotent stem cells, which can come from adult patients with diseased hearts, means scientists will be able to more readily model those diseases in the laboratory. Such cells contain the genetic profile of the patient, and so can be used to recreate the disease in the lab dish for study. Cardiomyocytes are difficult or impossible to obtain directly from the hearts of patients and, when obtained, survive only briefly in the lab.

The University of Wisconsin - Madison team found that manipulating a major signalling pathway known as Wnt - turning it on and off at prescribed points in time using just two off-the-shelf small molecule chemicals - is enough to efficiently direct stem cell differentiation to cardiomyocytes.