Each month CIRM President Alan Trounson gives his perspective on recently published papers he thinks will be valuable in moving the field of stem cell research forward. This month’s report, along with an archive of past reports, is available on the CIRM website.
This month’s literature produced a number of studies that can be glibly summarized as: Hey they work; they really work. The publications show we are starting to get a real handle on how to get stem cells to integrate and function like the desired tissue, and even to form complex structures.
The same Japanese team that was able to create a complex optic cup in a dish earlier this year, now reports that they have used embryonic stem cells to create a pituitary gland. That gland secretes the appropriate hormones and is able to correct hormone deficiency when transplanted into a mouse that lacks the pituitary gland, making the formerly lethargic animals active again.
Two teams turned embryonic stem cells into neurons that were able to integrate into the brain and show evidence that they function like the specific type of neuron that each team sought. A New York team produced dopamine-producing neurons that were able to correct some movement disorders in Parkinson’s disease models in mice, rats, and monkeys. (We blogged about that work here.) Meanwhile a Wisconsin team chose to mature the stem cells into neurons designed for memory, those in the hippocampus, and showed that they were able to integrate and fire neural signals like neighboring cells.
A Carolina team used a type of stem cell found in bone marrow and fat, mesenchymal cells, taken from the father of sheep with hemophilia, and correct the hemophilia in their sons. They did it by harvesting the stem cells and then genetically altering them so they produced Factor VIII, the blood-clotting factor that hemophiliacs don’t produce. When given to the sons, their bleeds stopped including the bleeds into their joints that had made them limp badly. The animals were able to walk normally again after the injections.
I start this month’s report with a pair of papers that seem to sort out some of the conflicting data that has been reported on stem cells for heart repair. One showed that stem cells from the bone marrow given in a couple of weeks after injury do not do improve heart function. Another showed that a different cell type—cardiac stem cells harvested from the patient’s heart—given even months after evidence of heart failure, were able to improve heart function, and in some patients for at least a year. (We blogged about that work here.) This is a critical area to gain some clarity in what cells to use and when; the burden of heart failure is a huge drain on our nation and the world.
My full report of this month’s highlights is here. I hope you will find it interesting.