Manmade ‘bioartificial organs’ on horizon
Prof. Dr. Dimitrios Stamatialis
In the not-too-distant future, manmade organs could transform the lives of patients whose kidneys, pancreas or lungs are failing. That’s the hope of Prof. Dr. Dimitrios Stamatialis, from the Department of Biomaterials Science and Technology at the University of Twente in The Netherlands, who is also a chairman of a working group on bioartificial organs established in 2016 by the European Society of Artificial Organs.
Recreating the genius of living membranes is extremely complex, but the field of bioartificial organs is advancing. In March 2017, Stamatialis and colleagues published on their creation of a functioning bioartificial kidney after ten years of work, an achievement scientists in various groups around the world have been striving towards since the late 1980s. And in August 2017 Stamatialis and his team published a paper about their work engineering a bioartificial pancreas.
Bioartificial organs are built using a combination of healthy human cells (grown from organ tissue discarded during surgery) and biomaterials. For example a bioartificial kidney is made from kidney cells ingeniously attached to a ′membrane′, a porous capillary engineered from artificial polymer fibre.
When human plasma is pumped through this tube, it reaches the kidney cells, which recognise toxins and remove them. This bioartifical kidney can filter and detoxify the blood in vitro, mimicking a real, healthy kidney.
IF WE DREAM A BIT, WE WOULD LIKE THIS SYSTEM TO BECOME IMPLANTABLE AND REPLACE THE KIDNEY ITSELF IN THE LONG TERMProf. Dr. Dimities Stamatialis
The bioartificial kidney Stamatialis’s team have created is a small ’bioreactor’ rather than the size and shape of a real kidney, while other researchers are 3D printing life-size kidneys from polymers populated with kidney cells.
Such organs could be transplanted into patients in the future to replace failing organs, but also will make research and drug testing safer. For example, bioartificial lungs will be a way for scientists to study how real lungs work.
“If we dream a bit, we would like this system to become implantable and replace the kidney itself in the long term,” says Prof. Stamatialis. If a bioreactor could be successfully transplanted into a patient with kidney failure, they wouldn’t need dialysis anymore. Similarly, an engineered pancreas made with pancreatic cells could treat diabetes.
Prof. Stamatialis is also working on developing better artificial kidney systems - without biological cells. If these could be applied to portable dialysis devices, patients wouldn’t have to spend hours in hospital each week.
’Organs on chips’ are also in development. These are small-scale replicas of organs which can be used to test drugs quickly and efficiently, or understand diseases. This is expected to result in less animal testing and in the development of new, cheaper medicines. A ′kidney on chip′ is made using the same kind of system as a bioartificial kidney, but the tube with human kidney cells attached is only a few millimeters long - in effect it’s a tiny kidney. “If you create 50 of those, you can test several drugs at the same time,” notes Prof. Stamatialis.
The artificial kidney for use outside the body, which could replace dialysis, has proven successful in laboratory studies and 2018 tests will start in animals. Stamatialis thinks it may be available for patients within five to ten years. For bioartificial organs, though, there is still a great deal of research to do, he says. ‘I don’t even dare to tell you a date - we need more tests to test the safety of the system before we go into clinical trials.’
“Every organ has its own requirements. In the case of the pancreas, pancreatic cells have to detect the concentration of glucose in the patient’s blood and then produce insulin to regulate the glucose,” says Stamatialis, “To replicate that, you need an interface between the cells and the blood plasma, allowing quick detection of glucose levels and quick insulin delivery”
“The liver is also responsible for blood detoxification, and an engineered bioartificial liver has some similarities to the bioartificial kidney. However, the liver cells have higher demands concerning nutrients and oxygen. So one needs to adapt the engineering concept for each organ.”
To bring this technology to patients, the team has challenges ahead. “To engineer an bioartificial organ, you need to understand very well what the cells do, where they come from, what are their regulatory aspects, how we’re going to implement them, how expensive this will be,” says Stamatialis, “All these things require investigation.”