Plasma donation: 'Why your blood matters so much to me'
Luke, 21, was diagnosed with lymphoma - a form of cancer - when he was 16.
The treatment left his immune system weakened, and unable to fight off illness as well as it used to.
He gets infusions of immunoglobulins once a month to help strengthen his immune system.
Around 17,000 people in England rely on the medication, made from blood plasma donations.
For years the UK imported plasma because of fears of mad cow disease, but donations in England and Scotland have recently started up again.
NHS Blood and Transplant wants 30,000 new donors, including 5,000 men aged 18-25, to help make plasma medication cheaper and more readily available.
Anyone can donate but younger men make good donors because they have high blood volumes, high iron levels and visible veins.
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