An article published in April’s Nature Medicine describes truly futuristic science. The article describes early attempts at growing new, functional organs.
The idea of growing new organs has long existed, but only as a science-fiction concept. The dream goes: what if we could take stem cells, put them in a petri dish, and grow a new organ? The problem is that stem cells don’t spontaneously do that. Embryogenesis (the process by which a fertilized egg grows into a new person) is far beyond our comprehension. We know what organs form at what stage of life, but we don’t understand the miraculously complex interplay of cellular signals and biological processes that drive the development of the baby and all its organs so precisely. We do not have the ability to take stem cells, put them in a petri dish, and selectively induce a new organ to grow.
The breakthrough described in the article is a testament to human scientific ingenuity. Researchers took animal kidneys and “de-cellularized” them. Essentially, this means they chemically treated existing organs to remove/wash away the living tissue such that what remains is organ-specific scaffolding. The scaffolding for the kidney has spaces for all the necessary structures: blood vessels, cells that filter blood, and cells that make urine.
Now, although we don’t know how to get stems cells to do what we want, it turns out they are pretty smart. If the scaffolding of an organ is already in place, properly-selected cells will differentiate into appropriately-functioning cells. Inoculation of the right cells onto a kidney scaffolding results in growth of a new, functional kidney. Sort of. These early organs function only at low capacity at present, and they have only been tested for brief periods of time. To be medically useful, the organs ultimately need high levels of function and long life-spans. These are early days with this new science, and the published results suggest proof of concept.
As Shakespeare wrote: “What a piece of work is man! How noble in reason, how infinite in faculty!” (Hamlet; Act II, scene ii). This is impressive science. It heralds the potential for amazing things. Looking way off to the future, one could foresee growing organs (kidneys, lungs, livers, or hearts) for transplant when a person’s own organs fail.
While such a vision is still years (probably decades) away, the science is promising and provides a pathway that could be a viable step toward growing new organs. Truly amazing.
source: Regeneration and experimental orthotopic transplantation of a bioengineered kidney (Nature Medicine)