Thursday, July 4, 2013

George Daley Explains How "Differentiated" iPS Cells Aren't Differentiated Enough

Signals just published my summary of a lecture given by George Daley, of Children's Hospital Boston, during one of his recent visits to the University of Toronto.

In his fact-filled yet congenial talk, he managed to convey a key message: that many techniques currently used to differentiate, or convert, induced pluripotent stem cells (iPS cells) don't perform as well as people assume.  From Signals:
Daley showed that pathway activation and deactivation can be monitored in differentiation experiments converting mouse embryonic fibroblasts to induced hepatocytes (iHeps), and that the cells, previously considered to be terminally differentiated hepatocytes, expressed posterior gut genes like Cdx2.

Exploiting this data, the group was able to repeat the differentiation experiment and showed that additional inhibition of activity within the Cdx2 signalling module produced improved iHep performance in terms of albumin and urea production.
So through this example he managed to convince many that though making new liver cells from iPS cells that look and act like liver is currently possible, there's always room for a little improvement. And in biology, that last little quantum of function might make a giant difference in terms of real world performance.

Check out more of the summary at Signals, here.