Sean Palecek, Ph.D.

During the National Academy of Sciences annual meeting awards ceremony, April 28, 2013, in Washington, D.C., Chemical and Biological Engineering Professor Sean Palecek will receive the Proceedings of the National Academy of Sciences 2012 Cozzarelli Prize. This prize recognizes Palecek’s PNAS paper, “Robust cardiomyocyte differentiation from human pluripotent stem cells via temporal modulation of canonical Wnt signaling,” for its outstanding scientific excellence and originality. PNAS is one of the world’s most-cited multidisciplinary scientific serials, with coverage spanning the biological, physical and social sciences. The award was established in 2005 and named in 2007 to honor late PNAS Editor-in-Chief Nicholas R. Cozzarelli.

The blood-brain barrier — the filter that governs what can and cannot come into contact with the mammalian brain — is a marvel of nature. It effectively separates circulating blood from the fluid that bathes the brain, and it keeps out bacteria, viruses and other agents that could damage it.

But the barrier can be disrupted by disease, stroke and multiple sclerosis, for example, and also is a big challenge for medicine, as it can be difficult or impossible to get therapeutic molecules through the barrier to treat neurological disorders.

Now, however, the blood-brain barrier may be poised to give up some of its secrets as researchers at the University of Wisconsin-Madison have created in the laboratory dish the cells that make up the brain’s protective barrier. Writing in the June 24, 2012 edition of the journal Nature Biotechnology, the Wisconsin researchers describe transforming stem cells into endothelial cells with blood-brain barrier qualities.

Cardiomyocytes, the workhorse cells that make up the beating heart, can now be made cheaply and abundantly in the laboratory.

Writing this week (May 28, 2012) in the Proceedings of the National Academy of Sciences, a team of Wisconsin scientists describes 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. 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 specialized heart cells.

“Our protocol is more efficient and robust,” explains Sean Palecek, the senior author of the new report and a University of Wisconsin-Madison professor of chemical and biological engineering. “We have been able to reliably generate greater than 80 percent cardiomyocytes in the final population while other methods produce about 30 percent cardiomyocytes with high batch-to-batch variability.”