Asked by: Andrew Spero, South Croydon
The idea of having an endless supply of artificial blood to give patients, without worrying about matching blood groups or passing on infection, has fascinated medical researchers for decades. Some substitutes based around haemoglobin (the crucial oxygen-carrying protein in blood) have been developed in the lab. But research published in 2008 revealed that these carried a substantial risk of triggering heart attacks or even death among patients receiving them.
Fortunately, a more promising approach has recently emerged, based on using stem cells to generate real blood to order. Pioneered by researchers in the United States, it has yet to undergo clinical trials, and could yet prove another false dawn. For the time being, the quest to recreate the red stuff coursing through our veins is set to continue.
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