A team of researchers at Cardiff University has discovered stem cells in the cheek can be used to supress the immune system. It should help patients with certain types of diabetes, and those whose bodies reject organs after transplants.
It'll be several years before a treatment's developed but the scientists say it's a real breakthrough.
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It will be a frosty start with a risk of ice. The rest of the day will be dry with variable cloud and sunny spells.
Any remaining wintry showers will die away through the first part of the night.
Cold and bright with some showers. It will be a cold start to the day, with some icy patches possible.