Rafael Matesanz
Creator and founder of the National Transplant Organisation.
This is undoubtedly an excellent article, the result of collaboration between several Spanish and international institutions, led by the Institute for Bioengineering of Catalonia, on the topic of organoids, which have great future potential.
Organoids are reduced and simplified versions of a human organ, grown in the laboratory. They are composed of different cells organized into small, three-dimensional structures, ranging in size from microns to centimeters, similar to living tissues or organs, in this case, the kidney.
Although there are various ways to produce them, starting from different cell types, those of most interest to us for this type of transplantation study are those generated from induced pluripotent stem cells (iPSCs). However, one of the main problems until now has been the difficulty of generating them in a simple and reproducible way.
The greatest value of this article is probably its first-ever description of a systematic and scalable method for producing these human kidney organoids in significant quantities and affordably, using microaggregation techniques and genetic engineering. The procedure described here could be highly useful in future research.
Regarding the second part of the article, the attempt to make these organoids suitable for transplantation, it's important to remember that the biggest problem is that, to date, we haven't been able to get them to develop an adequate blood vessel structure. Therefore, they can be used for drug testing, studying organ development, or other applications, but not for transplantation. For this reason, the approach of this work is original and potentially valuable for future research, as it successfully infuses human kidney organoids into porcine kidneys using normothermic perfusion machines commonly used in clinical practice.
The researchers achieved a breakthrough: after transplanting these modified porcine kidneys into other pigs, the infused human organoids remained integrated into the porcine kidney tissue, maintaining its viability and without triggering significant immune responses. This could pave the way for a procedure to repair kidneys and improve their viability before transplantation.
It goes without saying that this part of the study is in the preclinical phase and is still very early, but the readily available and abundant supply of these kidney organoids could accelerate their transition to clinical practice, apart from the fact that the use of perfusion machines allows them to be introduced into the renal parenchyma and the changes induced by them in the kidney "under repair" to be perfectly evaluated.