Stem cells replace stroke-damaged tissue in ratsMarch 9th, 2009 - 11:57 am ICT by IANS
London, March 9 (IANS) Effective stem cell treatment for strokes received a boost when scientists succeeded in replacing stroke-damaged brain tissue in rats.
Their work, carried out at the Institute of Psychiatry, London and University of Nottingham, shows that by inserting tiny scaffolding with stem cells attached, it is possible to fill a hole left by stroke damage with brand new brain tissue within seven days.
Previous experiments where stem cells have been injected into the void left by stroke damage have had some success in improving outcomes in rats.
The problem is that in the damaged area there is no structural support for the stem cells and so they tend to migrate into the surrounding healthy tissues rather than filling up the hole left by the stroke.
Mike Modo who led the research team said: “We would expect to see a much better improvement in the outcome after a stroke if we can fully replace the lost brain tissue, and that is what we have been able to do with our technique.”
Using individual particles of a biodegradable polymer called PLGA that have been loaded with neural stem cells, the team of scientists have filled stroke cavities with stem cells on a ready-made support structure.
“This works really well because the stem cell-loaded PLGA particles can be injected through a very fine needle and then adopt the precise shape of the cavity. In this process the cells fill the cavity and can make connections with other cells, which helps to establish the tissue.
“Over a few days we can see cells migrating along the scaffold particles and forming a primitive brain tissue that interacts with the host brain. Gradually the particles biodegrade leaving more gaps and conduits for tissue, fibres and blood vessels to move into,” said Modo.
The research uses an MRI scanner to pinpoint precisely the right place to inject the scaffold-cell structure. MRI is also used to monitor the development of the new brain tissue over time, said an Institute of Psychiatry release.
The next stage of the research will be to include a factor called VEGF with the particles. VEGF will encourage blood vessels to enter the new tissue.
The study was published in Biomaterials.
Tags: biodegradable polymer, brain tissue, cavities, cell structure, conduits, fibres, filling up the hole, institute of psychiatry, institute of psychiatry london, london march, mri scanner, neural stem cells, new brain, plga, precise shape, scaffold, scaffolding, stroke damage, support structure, university of nottingham