We are learning how to grow organs in laboratories instead of relying on donors, says Philip Hunterby Philip Hunter / February 20, 2014 / Leave a comment
Alexander Seifalian with the glass mould of a trachea built by his team at UCL © STELLA PICTURES
When a patient suffers from a malfunctioning internal organ, the best course of action can sometimes be to replace it. The ability to do this is not new—the first heart transplant was performed by the South African surgeon Christiaan Barnard in 1967. The first kidney transplant had taken place 17 years previously and a liver had been transplanted in 1963; but unlike the heart transplant these involved more straightforward procedures, without the complexity of reconnecting the patient’s cardiovascular system. Survival rates increased for heart transplants as the technology improved, but organ transplantation has always been hindered by the shortage of suitable donors. As a result the majority of people seeking organs never receive them. Even for those lucky enough to find donors, donated organs can sometimes be little better than those they are replacing.
But new research has promised to bring about substantial progress in replacing diseased organs—not with tissue taken from donors, but with organs grown in laboratories. Technology is helping scientists to construct tissue using new techniques and this material is then transferred into the patient. If these techniques are perfected, they may lead to a significant increase in the human lifespan and a profound change in the way that medical science confronts disease.
Problems with the availability of donor organs have, in the past, led to interest in alternative approaches such as manufacturing artificial organs and xenotransplatation from animals. However, these lead to a complex set of problems, such as the risk of infection and tissue rejection. An added complication is that artificial organs tend to lack the full functionality of the real thing.
However, scientists are now able to make new organs using a patient’s own adult stem cells. This will bring hope to the many people suffering from diseased organs who have little prospect of finding a suitable donor.
The potential of stem cells first became apparent just over a decade ago, following a series of advances. The key step was taken in 1981, when Gail Martin at the University of California, San Francisco, first isolated embryonic stem cells in mice. Following this breakthrough, the initial focus was on manipulating cells to regenerate tissue or organs in situ, rather than externally in the lab—“in vitro.” There was profound ethical alarm…