Donations of blood plasma in England for use in the manufacture of "lifesaving" medicines are to begin after the lifting of a ban lasting more than two decades.
For an initial three months from Wednesday, donations will be taken at 14 centres across the country.
These will be used to make antibody-based medicines, called immunoglobulins, for people with rare immune diseases.
Natalie Beeton, 26, from Borehamwood, relies on immunoglobulin medicines to protect against serious illness due to her immunodeficiency.
Doctors believe her immune system was damaged by glandular fever and she has been receiving an antibody transfusion every six weeks at London’s Royal Free Hospital since July 2019.
She said: "It pretty much killed my immune system."
Ms Beeton, an underwriter for a financial company, is going through tests for common variable immune deficiency (CVID).
She added: "I was at constant risk of serious infections because my immune system could not stop anything.
"My illness is long term and I am going to need this medicine for the rest of my life. Donations are the juice that keeps me going."
In February, the Government lifted a ban which was imposed on UK donors in 1998 amid concerns about the spread of a human variant of bovine spongiform encephalopathy (BSE), known as Creutzfeldt-Jakob disease (CJD).
NHS Blood and Transplant (NHSBT) said around 17,000 people needed immunoglobin therapy in 2018/19 for a range of diseases and genetic disorders.
These included immune disorders such as CVID and neurological disorders like Guillain–Barre syndrome and myasthenia gravis.
The medicines are also used to help treat cytopenia, a disorder featuring a low mature red blood cell count which can occur following radiotherapy and chemotherapy for cancer treatment, as well as dermatological disorders like Kawasaki syndrome and toxic epidermal necrolysis.
Amid a global supply shortage due to rising demand, the UK has previously depended on imports of blood plasma from other countries – mainly the US.
Dr Gail Miflin, chief medical officer for NHSBT, said: "Plasma is made into lifesaving medicines for people with rare diseases.
"There is a growing need for plasma for medicines and a worldwide shortage of donors."
She said a "dedicated plasmapheresis programme" would "greatly increase NHSBT’s ability to provide plasma at volume" and reduce the reliance on plasmas from overseas.
Donations will be taken at repurposed former convalescent centres originally created for coronavirus research.
They are in Stockton, Barnsley, Manchester, Bolton, Birmingham, Coventry, Wolverhampton, Chelmsford, Reading, Bristol, Croydon, Stratford, Tottenham and Twickenham.
More than 1,500 people, drawn from an existing blood donor base, are booked in to donate in the first week, with open recruitment to be introduced in the future.
Sue Dimmock, acting chairwoman of UK Primary Immune-deficiency Patient Support (UKPIPS), said: "Those of us who are unable to make our own antibodies completely rely on regular infusions of donated, plasma-derived antibodies (immunoglobulin) to fight infection and to stay as healthy as possible.
"Without this treatment, we have an extremely limited defence against infection and disease."
Minister for innovation Lord Bethell hailed the “historic occasion” and urged people thinking about donating plasma to "absolutely take the plunge".
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