|Alan Trounson, CIRM President|
This month I want to focus my blog on a paper that I think is a major advance in spinal cord injury repair. A CIRM-funded UC San Diego team mixed stem cell science with some classic tissue engineering to achieve the greatest degree of spine repair in rats that I have ever seen reported (you can read a summary of their award here). They embedded neural stem cells in fibrin, a protein found in blood, and added several growth factors to this gel.
When you use neural stem cells is it is not good enough for them to just mature into neurons. Those neurons need to produce lengthy axons that can reach out and make connections with the existing neurons in the host. The UCSD team placed the gel at the site of complete spinal cord separations in rats and after six weeks found that the number of axons growing from the injury site exceeded what other teams had seen by 200-fold. Those axons also grew10 times the length seen in earlier studies.
They found this when they implanted rat neural stem cells as well as with two different human neural stem cell lines. One of those human lines is already approved for use in humans and is being tested in a clinical trial for ALS (Lou Gerhig’s disease). This could greatly reduce the time needed to move the UCSD process from animal testing to human trials.
My colleagues wrote about this work when it first appeared in the journal Cell here.
This month’s report also includes two articles showing that the field continues to make major strides in understanding and refining the process of reprogramming adult cells to become cells that behave like embryonic stem cells, that is iPS cells. We blogged about one of these papers here. My report also discusses a paper that firms up the role of cancer stem cells in leukemia.
My full report is available online, along with links to my reports from previous months.