In a glass cube filled with a transparent liquid, a curious red object floats, the size of a cherry. It is the first artificial heart created from human cells. It was manufactured by 3D printing, an automated process that consists in producing something by depositing successive layers, usually plastic, here cells. This feat, expected for years by the world of science, was unveiled on April 15 by Israeli researchers at the University of Tel Aviv, in the German magazine Advanced Science.
Certainly, this heart, the size of that of a rabbit (2 cm in diameter), is currently tiny. But the step that has just been taken is crucial because it makes tangible the idea of creating new organs tailored to treat us. In 2017, in France, 6105 organ transplants were performed, including 629 from living donors, according to the Agency for Biomedicine. But it is difficult to find enough donors. We can give some organs in our lifetime, like the kidney.
Make the patient his own donor
Other organs, such as the heart (467 transplants in France, in 2017), can only be collected from people who have just died. In addition, they must be compatible with the body of recipients so that the transplant is accepted by the body of patients. Faced with these constraints, the project to grow artificial organs from the patient's cells was born in the early 2000s.
The idea was to make the patient his own donor. "Compared to other artificial heart projects, such as that of the French company Carmat, for example, our body has the advantage of being well accepted by the body of the patient," said Dr. Assaf Shapira, one of the leaders Works. There will be less chance of provoking violent immune responses. "
Duplicate the shape and function of the organ
To move from theory to practice, the task is difficult. Reproducing a custom organ requires achievements in medicine, but also in materials science, because it must duplicate both its form and function. 3D printing from human cells, also called "bio-printing", made it possible to pass this course.
"Any complex organ, be it the heart, the liver, the kidneys or the lung, is difficult to conceive, because one must be able to recreate its exact cellular composition, but also its physical and biochemical activity to be functional. and effective over time, "continues Assaf Shapira. The heart, for example, must be able to contract and pump blood. According to the researcher, several years of work will still be needed before it can be fully achieved.
In the meantime, the Israeli team hopes to obtain other promising intermediate results, such as creating artificial patches that can be positioned on a heart and help it function well after a heart attack. On this point, a British team from Imperial College London has taken the lead. In early June, they said they managed to make such a patch from patient cells. They believe they can deploy it in two years on patients.
One type of artificial lung under study
The heart will not be the only body to benefit from advances in 3D printing. In May this year, US researchers at Rice and Washington Universities made an object that replicates the movements of the lung: it swells and shrinks when air flows through it.
The Wake Forest Institute, still in the United States, had pioneered, as early as 2016, the 3D printing of an ear with human cells. "We are currently working on more than 40 different organs and tissues," says Anthony Atala, director of the university. "The simplest structures, like that of the skin, begin to be well controlled, but those of solid organs, including the liver, will be more difficult to achieve because they are highly vascularized and they have very high nutritional needs" he concedes. The bank of artificial organs available to measure and on demand is not for tomorrow. But for the day after tomorrow, everything remains possible.
A kidney delivered by drone
A world premiere took place on April 19 at the University of Maryland in the United States. A kidney was transported by drone and could be grafted in the wake to a dialysis patient since 2011. The flight was short (only ten minutes to cover 3 km), but it proves that it is possible to use this unmanned means of transport to reach patients waiting for transplant very quickly.
In Canada, Unither Bioelectronics is also preparing for an experiment. "We are going to start testing drones this summer and, hopefully, the first regular organ transports could be effective next year," says Mikaël Cardinal, project manager.