|iPS cells reprogrammed from human skin. These cells are being used for “disease in a dish” studies to unlock the causes and eventually treatments for diseases such as Alzheimer’s and heart disease. (image: lab of Kathrin Plath, UCLA)|
With Nobel prize winning stem cell researcher Shinya Yamanaka heading the bill at the annual meeting of the International Society for Stem Cell Research (ISSCR) in Boston it was always likely that research focusing on the discovery that earned him the prestigious award was going to be a prominent part of the conference.
And it is.
Yamanaka’s discovery is, of course, how to create induced pluripotent stem cells (iPS), adult cells such as skin that are capable of becoming any other cell in the body. On Thursday, research focusing on ways of using those cells to get a better understanding of different diseases and, ultimately, to help develop treatments for them, took center stage.
Two CIRM-funded researchers, Dr. Larry Goldstein of UC San Diego (here’s a video of Goldstein talking about his work) and Dr. Joseph Wu of Stanford present their efforts to use iPS cells to delve into the mechanisms behind Alzheimer’s and heart disease respectively.
Goldstein says while Alzheimer’s is an increasingly common diagnosis – 10 percent of people over 65 and 50 percent over 85 have it – the actual cause of the disease is still not well understood. There are lots of theories but no really solid understanding or hard evidence to pinpoint what’s behind it.
That’s where iPS cells come in. By taking skin cells from six patients – two without Alzheimer’s, two with the familial or inherited version, and two with the more common sporadic form – and then turning those skin cells into neurons, the kind of brain cell that is affected by Alzheimer’s, Goldstein is able to compare the different genetic makeup of the cells. He’s trying to pinpoint where they are different and what may be increasing a person’s risk of the disease.
It’s painstaking and subtle work. He says because Alzheimer’s typically develops over decades the differences in the cells that cause the disease may be small and take time to identify. But thanks to iPS he now has a tool that enables him to test his research in human brain cells, rather than animal models.
For Dr. Wu iPS cells are just as important in his work with heart disease. He takes skin cells from people with inherited forms of heart disease – such as familial dilated cardiomyopathy, the most common cause of heart transplants in infants and young adults – and then converts those skin cells into heart cells.
He can then use those heart cells to study the genetic causes of the disease and also to screen drugs to see if they are both safe and effective against it. He can also look at other drugs to see if they pose a threat to patients with heart disease. That’s important because there are a number of commonly prescribed medications that are toxic to the heart; knowing which ones are likely to be dangerous for patients with particular conditions can help save lives.
Wu’s hope is to develop what he calls a “clinical trial in a dish model”, one that would allow you to test, in a fast and effective way, if a drug is appropriate and safe for a patient with a particular heart condition. In essence it would be customized drug screening for individual patients. That’s likely to be several years away, but without iPS cells it wouldn’t even be a possibility.