Donor organs are hard to come by partially because of ischemic damage, physical damage, presence of infection, and other reasons. Researcher at the University of Toronto in Canada and University of São Paulo in Brazil have developed a method of getting rid of bacteria and viruses from donor organs using only light.
The technique involves first removing all donor blood from the organ, running a preservation liquid through the organ, and illuminating organs using ultraviolet and red light for about a half hour or so. In order to boost effectiveness, a photosensitizing drug is introduced into the liquid that is activated by the red light, which in turn oxidizes any pathogens nearby. The perfusion aspect is already a standard of care, but it can’t completely get rid of all pathogens, so the light and photosensitizing drug finish off anything left over.
The new technique was tried by transplanting a lung from a donor pig that was infected with hepatitis C into another pig. The lung received light therapy during normothermic ex vivo lung perfusion, and the recipient pig went on to fare quite well and avoided becoming infected with hep C.