“The concept of being able to have an organ waiting on the shelf, waiting for the person who needs it, is just remarkable to think about, and exciting for that person.

“I feel really privileged to be just a tiny part of a really big puzzle that people have been working on for many years.”

One major question which has now been answered was whether pig organs could cope with the higher blood pressure in humans. The pig kidney coped just fine, the scientists report in their study, published in the American Journal of Transplantation.

As a result of this vital advancement in the field, Dr Locke has named the experiment, which will likely be used in future as a blueprint to ensure animal organs are safe for people, “The Parsons Model”.

Ms Julie O’Hara, the ex-wife and friend of Mr Parsons, said: “I cried when [Dr Locke] told me about that proposal, to name this after Jim.”

“Jim would have wanted to save as many people as he could with his death, and if he knew he could potentially save thousands and thousands of people by doing this, he would have had no hesitation,” said Ms O’Hara.

“Our dream is that no other person dies waiting for a kidney, and we know that Jim is very proud that his death could potentially bring so much hope to others.”

Still a ‘long way’ to go

Prof Gabriel Oniscu, president-elect of the European Society of Organ Transplantation and director of the Edinburgh Transplant Centre, told The Telegraph: “This is another landmark study on a number of levels.

“All of a sudden, we’ve created potentially a new way of testing [xenotransplant] therapies prior to going to clinical trials.”

He added that the experiment was “great progress” but still experimental and we are a long way from xenotransplants becoming a reality.

“Xenotransplants will not be an option for everyone, but they may become an additional option. Until that happens and we know that it’s safe, we still need to rely on donations.”