Scientists have for the first time successfully engineered a synthetic kidney, a breakthrough that could have massive benefits for those waiting for donor organs.
Scientists led by Harald Ott of the Massachusetts General Hospital in Boston created the synthetic kidney using an existing bioengineering process that has previously been used in the manufacture of artificial windpipes and then in successful human transplants.
In this case, details of which were released in the science journal Nature Medicine this week, the research team crafted a rat kidney made from the scaffold tissue of a dead rat’s kidney that had been stripped of its own cells using what is known as an enzymatic detergent.
The team then infused the scaffold with the rat’s own skin and blood cells. The team, who developed this technique in 2008, have announced they have also successfully created synthetic pig and human kidneys, though the viability of human transplantation is still some way off. Nevertheless, this research is uniquely promising.
Why? The approach could enable us to dramatically reduce the risk of organ rejection and would likely eliminate the need for immunosuppressing drugs because the organ would contain the patient’s own cells and therefore the patient’s immune system would be less likely to attack the organ.
There are some drawbacks to this process, however.
The study notes that while the artificial organ was able to filter blood to produce urine — both in a controlled lab setting and when implanted in a rat host — the organ only functioned about a third as well as a comparatively sized adult kidney. Researchers have put this down to the process used to engineer the kidney, which involved harvesting cells from a rat fetus in order to make the blood vessels and the filtration cells of the organ. This issue will be tackled in later research.
“Further refinement of the cell types used for seeding and additional maturation in culture may allow us to achieve a more functional organ. Based on this initial proof of principle, we hope that bioengineered kidneys will some day be able to fully replace kidney function just as donor kidneys do,” Dr Ott is quoted as saying. “In an ideal world, such grafts could be produced on demand from a patient’s own cells, helping us overcome both the organ shortage and the need for chronic immunosuppression.”
It should also be noted that most patients with kidney disease start dialysis only after their kidney function drops below the 15% mark. As such, if a graft were available with only 20% functionality it would still be enough to make patients independent of hemodialysis and therefore deliver a marked improvement in quality of life.
Those suffering from the most severe forms of kidney disease must rely on dialysis until a transplant opportunity becomes available. This can dramatically reduce a person’s well being and, even if the patient is lucky enough to find an organ match, there is no guarantee that a future transplant will yield a positive result as rejection is always a risk.
It is estimated that some 100,000 people in the United States are waiting for a donor kidney. The above research will not yield a viable organ for human transplantation for a number of years yet, but the techniques used here are incredibly promising for future research and point to one day reaching the goal of being able to quickly manufacture new organs for those in need, something that could save countless lives.
However, and with all cases where animal testing is used, this research brings up a number of ethical questions including whether it is ever justifiable to use animal research to further the aims of medical science.
Image credit: Thinkstock.