Researchers pump human cells in rat lung that has had its own cells removed. Source: Ott Lab
Organ transplantation is a miracle of modern science. However, it has one big pipeline problem: roughly 20 people die every day in the United States alone while waiting for an organ transplant. Scientists at Harvard Medical School think they can solve that downside by sprucing up old organs from pigs and animals, giving the organs and their new owners alike a brand new lease on life.
Surgeon Dr. Harald Ott and his research lab have developed a technique that strips animal organs of their cells by washing them in detergent, leaving behind a tissue scaffold that can then be seeded with human stem cells from the patient in need. This could prevent a patient’s body from rejecting the organ, and mean that transplantees wouldn’t have to spend their lives on anti-rejection medication. Because the cells grow on this scaffold, the lab uses a bioreactor that pumps the organ, maintaining its health by stimulating it in the same way it might move in the body.
The process begins by hooking the circulatory system of an animal organ, e.g in this case a pig lung, to a pump that sends detergent through the organ.
They have also used the same process to successfully remove cells from human lungs for use as scaffolds, as shown here.
The research team has successfully refurbished hearts, kidneys, lungs, and portions of intestines from pigs and rats to make them human-donor suitable, and then transplanted these organs back into animals. Although the human cells in these transplanted organs made them incompatible with the pigs’ and rats’ bodies, the organs worked — exhibiting significant promise for future human trials. The lab also successfully re-grew muscle inside human cadaver hearts that had been similarly stripped of their original cells.
A ‘refurbished’ human heart partially re-seeded with human stem cells being cultured in a bioreactor. Picture credit: Bernhard Jank, Ott Lab, Center for Regenerative Medicine, Massachusetts General Hospital
“Your iPhone breaks, your battery breaks, you switch it out. Medicine, in some ways, is possibly shifting in that direction… I could measure you up, basically, take an organ off a shelf, ideally make it personalised so that your body wouldn’t reject it, and then I would implant it into you.” Ott told the Wall Street Journal.
Nonetheless, Ott estimates will probably be at least a decade before these organs might be ready for clinical trials in humans. In the meanwhile, Ott is amongst a large group of scientists in search of improving the transplantation process. From gene editing pig organs for humans to better methods of preserving donor organs, to even bio-printing and growing human organs in the lab, the period of patients waiting endlessly on transplant lists might possibly be coming to an end.
