Sir Michael Francis Addison Woodruff, FRS, FRSE, FRCS (3 April 1911 – 10 March 2001) was an English surgeon and scientist principally remembered for his research into organ transplantation.

Having completed his studies shortly after the outbreak of World War II, he joined the Australian Army Medical Corps, but was soon captured by Japanese forces and imprisoned in the Changi Prison Camp.

At the conclusion of the war, Woodruff returned to England and began a long career as an academic surgeon, mixing clinical work and research.

While at the university, he passed the primary exam for the Royal College of Surgeons in 1934, one of only four successful candidates who sat the examination in Melbourne that year.

At that time, he was assigned to the Tenth Australian Army General Hospital in British Malaya as a captain in the Medical Corps.

The Japanese attack on Pearl Harbor changed the situation and he was posted to a casualty clearing station where he worked as an anaesthetist, before being transferred into the Singapore General Hospital.

In the camp, Woodruff realised that his fellow prisoners were at great risk from vitamin deficiencies due to the poor quality of the rations they were issued by the Japanese.

[7] He devised a method for extracting important nutrients from grass, soya beans, rice polishings, and agricultural wastes using old machinery that he found at the camp.

Woodruff later published an account of his methods through the Medical Research Council titled "Deficiency Diseases in Japanese Prison Camps".

[7] While stationed at the River Valley Road prisoner of war hospital in Singapore in 1945, with the supplies of chemical anæsthetics severely restricted by the Japanese, Woodruff and a medical/dental colleague from the Royal Netherlands Forces successfully used hypnotism as the sole means of anæsthesia for a wide range of dental and surgical procedures.

[9] In January 1946, Woodruff participated in an Australian Student Christian Movement meeting, where he met Hazel Ashby, a science graduate from Adelaide.

Woodruff took his new wife over with no guarantee of employment, and declined a two-year travelling fellowship to Oxford University offered by the Australian Red Cross because it required him to return home and work.

He took the FRCS exam in 1947 and passed—a result that, in Woodruff's view, was not hindered by the fact that one of his examiners, Colonel Julian Taylor, had been with him at Changi.

To further himself in these areas, Woodruff arranged to meet Peter Medawar, an eminent zoologist and important pioneer in the study of rejection.

[3][10] In 1948, shortly after applying for the position in Melbourne, Woodruff moved from Sheffield to the University of Aberdeen where he was given a post as a senior lecturer,[1] having not known where the Scottish city was beforehand.

[10] At Aberdeen, Woodruff was given better laboratory access under Professor Bill Wilson, and was also awarded a grant that allowed his wife to be paid for her services.

At the time, the surgical community hypothesized that if a recipient were given in utero grafts, he would be able to receive tissue from the donor later in life without risk of rejection.

During the visit, he met many of the leading American surgeons, an experience that increased his own desire to continue his work and research.

[3][12] In 1951 Woodruff was awarded a Hunterian Professorship of the Royal College of Surgeons of England for his lecture The transplantation of homologous tissue and its surgical application.

[3] Although Woodruff had been productive in his four years in New Zealand, Dunedin's population of 100,000 was insufficient to supply a clinical medical school, so he began to look for an appointment elsewhere.

[13] The research group's principal investigations concerned immunological tolerance (the body's acceptance of tissues, as opposed to rejection), autoimmune haemolytic anaemia (especially in mice), and immune responses to cancer in various animals.

Woodruff was deeply shaken by the loss and the unit was closed for a period while an investigation was carried out to develop a contingency plan to avoid such a disaster in future.

[17] Woodruff retired from the University of Edinburgh in 1976,[3] his role then being filled by Prof Geoffrey Duncan Chisholm,[18] and joined the MRC Clinical and Population Cytogenetics Unit.

[3] After retiring from his cancer research, Woodruff lived quietly with his wife in Edinburgh, travelling occasionally,[5] until his death there on 10 March 2001, a month before his 90th birthday.

Among these contributions, Woodruff's work with anti-lymphocyte serum has led to its wide use to reduce rejection symptoms in organ transplant recipients up to the current day.

[20] Despite his profound influence on transplantation and what Peter Morris called "a commanding presence in any gathering",[21] Woodruff was not known for his ability as a lecturer as he had a rather uncertain style of presentation and a tendency to mumble.

[21] Morris concluded that "What is surprising is that he was not successful in producing many surgeons in his own mould, despite the intellectual talent that was entering surgery and especially transplantation in the 1960s.

In addition to authoring over two hundred scholarly papers,[22] Woodruff wrote eight books during his career, covering numerous aspects of medicine and surgery.