Science breaks new ground in cell renewal


SCIENTISTS HAVE reached yet another milestone in the goal to produce replacement cells for any tissue type in the body.

A team from Stanford University in California have converted cells from a mouse’s tail directly into brain cells.

While much research remains to be done to confirm the breakthrough, the research team believes they have come up with effective way to produce any of the many tissue types in the body.

The goal as ever is to be able to produce healthy replacement cells as a treatment for conditions such as motor neuron disease and Parkinson’s. The method is much simpler to achieve than that developed in 2006 by Japanese scientist Shinya Yamanaka of Kyoto University.

Mr Yamanaka astounded the world’s science community by developing a way to take ordinary skin cells and make them revert to a cell type found in the developing embryo, pluripotent stem cells. These cells have the capacity to change into any of the more than 200 distinct cell types in the body.

Now a team at Stanford headed by Marius Wernig, an assistant professor of pathology at the Institute for Stem Cell Biology and Regenerative Medicine, has come up with a way to take connective tissue cells from the tail skin of mice and make this convert directly into neurons. They publish their findings this morning in the journal Nature.

The neurons can be produced without first having to push the skin cells back to being embryonic stem cells. It is a direct transition between the connective tissue cell, a fibroblast, and the neurons.

The earlier Japanese work relied on using four biochemical substances to make the skin cell convert to a pluripotent stem cell. In this new work, Prof Wernig came up with a combination of just three factors produced by genes in the neuron that were enough to make a connective tissue cell convert into a neuron.

He used an initial trial and error method, inserting 19 different genes found in neurons into the fibroblast. He was able to reduce this until he could make the fibroblast convert directly to neurons using just three genes.

The new approach carries huge implications for the advance of cell replacement research. Most of the work has been directed towards making pluripotent stem cells and then using them to produce replacement tissues.

Prof Wernig’s approach seems to be able to cut out the stem cell, changing cells directly into the replacement cell type required.