transplant

Syringes are used to harvest bone marrow from the pelvis of a donor prior to transplantation into a patient with leukaemia. Bone marrow is rich in blood-forming and immune system cells. Donated bone marrow can be used to save the lives of patients whose own marrow cells have been destroyed by the chemotherapy and radiotherapy needed to eradicate their cancers.

Sir Magdi Yacoub, pioneering surgeon who introduced many innovations in heart and heart-lung transplantation. Born in Cairo in 1935 and trained in Egypt and Britain, Magdi Yacoub has been British Heart Foundation Professor of Cardiothoraic Surgery at the National Heart and Lung Institute, Royal Brompton Hospital, London, since 1986.

In medicine, the transfer of a tissue or organ from one human being to another or from one part of the body to another (skin grafting). In most organ transplants, the operation is for life-saving purposes. The immune system tends to reject foreign tissue, so careful matching and immunosuppressive drugs must be used, though these are not always successful.

Corneal grafting, which may restore sight to a diseased or damaged eye, was pioneered in 1905, and is the oldest successful human transplant procedure. Of the internal organs, kidneys were first transplanted successfully in the early 1950s and remain most in demand. Modern transplantation also encompasses the heart, lungs, liver, pancreatic tissue, bone, bone-marrow, and ovarian tissue.

Most transplant material is taken from cadaver donors, usually those suffering death of the brainstem, or from frozen tissue banks. In rare cases, kidneys, corneas, and part of the liver may be obtained from living donors. The 1990 Nobel Prize for Medicine or Physiology was awarded to two US surgeons, Donnall Thomas and Joseph Murray, for their pioneering work on organ and tissue transplantation.

According to a survey published in August 2001, in the USA the number of patients awaiting transplants tripled in the period 1990-99, from 22,000 to 72,000, whereas the number of transplant operations increased by only about 50% from 15,000 to 22,000.

The first experiments to use genetically altered animal organs in humans were given US government approval in July 1995 - genetically altered pig livers were attached to the circulatory systems of patients who were near death or whose livers had failed. Need for the tests had arisen due to a shortage of human organs available for transplant.

In 1999 US researchers found that patients awaiting liver transplants could be kept alive by regular infusions of frozen liver cells. These cells are readily available as they can be taken from damaged livers unsuitable for whole-organ donation. One patient suffering acute liver failure made a full recovery after the cell infusions. Even very damaged livers may be capable of some regeneration.

The first transplant of a lung from a dead donor took place in October 2000. Although the recipient died in March 2001 of complications relating to a later liver transplant, the lung had continued to function efficiently.

In 2005 scientists announced a successful ovarian transplant to reverse the early menopause in a patient aged 14 years old. Tissue taken from an ovary donated by the patient's twin sister was grafted onto the patient's ovaries. After three months the patient experienced periods and shortly afterwards became pregnant naturally. This was the first time that a normal pregnancy and birth resulted from an ovarian transplant between two different women.