The Corpus Callosum

Biomedical Image Awards, etc.

i-77ae8a4d7f7389e8c370cf7eec9d8acf-2_tn.jpgThe
Wellcome Trust Biomedical Image Awards for 2006 have been announced.
 The winners can be seen href="http://www.wellcome.ac.uk/en/bia/gallery.html">here.

This photograph shows nerve cells growing along synthetic silk fibers.
 The tiny blue dots are href="http://en.wikipedia.org/wiki/Schwann_cell">Schwann
cells
.  Schwann cells are a type of glial cell that
form myelin sheaths.

The hope is that these fibers might enable us to guide the growth of
nerve cells, in order to repair damage.  The technology is
described in href="http://news.bbc.co.uk/2/hi/science/nature/5172422.stm">this
article in BBC News.

The silk, dubbed Spidrex, comes from silk worms that
have been modified to give the fibres special properties that help
cells to bind.

Professor John Priestley, a neuroscientist from Queen Mary’s School of
Medicine and Dentistry, London, and lead researcher, said the silk
acted as a scaffold on which nerve cells could grow.

The team has tested the silk in tissue culture (shown in the winning
image) and in animals – and in both cases, said Professor Priestly, the
results had been good…

…The team hopes the silk can be used to treat patients whose
peripheral nerves – the nerves that control muscle and provide
sensation – have been severed: someone who has received a bad cut to
the hand, for example.

A more ambitious goal, explained Professor Priestly, would be to use
the silk to help repair damaged spinal cords, but this would be much
more complex, he stressed. 

Unlike the nerves of central nervous system, in which the capacity for
regeneration is highly limited, peripheral nerves can regenerate.
 However, the process often does not work well.
 Usually, the patient is left with limited function in the
affected area.  See href="http://www.ucihs.uci.edu/ortho/pnrl/Peripheral%20Nerve%20Repair.pdf">this
page (75 KB PDF file) for a review of the challenges of
peripheral nerve repair, including the use of various types of axonal
guidance channels.