ITV News' Science and Medical Editor Lawrence McGinty explains that according to one leading researcher "it's not a cure for spinal cord injuries but it's the most encouraging advance for years".
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UKIP have made further gains in the local elections in the Anglia region and the Conservatives have won back control in Peterborough.
Labour have held Sunderland, Newcastle, Hartlepool and South Tyneside - but UKIP and the Lib Dems make some gains
Labour suffered losses in English council elections, but the initial results were not as bad as many had expected.