Need an organ? Print an organ.
Dr. Atala is head of Wake Forest’s Institute of Regenerative Medicine. Regenerative medicine is the answer to the twin problems of transplant medicine: we are not increasing the organ pool through living donation and rejection continues to limit the lifespan of transplants. The number of living donations has essential been plateaued for a decade and the improved one year rejection rates have not transpired into better long term graft survival.
Dr. Atala’s life work is building rather than transplanting organs. He started with synthetic scaffolding for cells to grow into. Subsequently he has progressed into more advanced techniques by adding tissue growth factors and human cells. The science of growth factors has allowed him to grow dozens of cell types. At this point he listed only a few cell types that still flummox him: liver, nerve, and pancreas. Heart cells are one of the newest cell types. By combining the synthetic scaffolding, cells, growth factors and especially angiogenesis growth factors (He talked about one of his early labs being down the hall from Judah Folkman and how that was the source of many early advancements) he can build tissues and, as he demonstrated, organs.
The simplest organ to recreate was the ureter. And by simplest, I want to emphasize it looked crazy hard and complex, but it was the first organ they tackled. The combination of scaffolding, cells and growth factors could create a centimeter of viable ureter, twice the distance scaffolding alone could correct. He emphasized that they were not stenting damaged tissue but creating new tissue made of human cells. He showed mouse and human data including a case series of 5 patients. The same approach can be used for blood vessels, trachea, heart valves, and other tubular organs.
Part of this technology included using 3D printers. Some print jets were loaded with matrix-scaffolding material and other jets were loaded with cells and growth factors. He even has been partially digesting living tissue and scanning the underlying tissue scaffolding and using that scan to build a 3D model for his printer. He was really excited about the 3D printer because it gave him a means to use automation to scale up organ production.
After tubular organs he advanced to pouch and spheroid organs. He shared his success building functional vaginas and bladders. He said that the vaginas are fully innervated and that his bladders were able to grow with the patient. Unbelievable.
The last frontier of organ regeneration was solid organs. His team has been working on building penises since the 90s. He has success in rabbits where he was able to build functional phalluses that are reproductively functional. He is now working with the VA and wounded warrior project to bring the technique to humans.
The climax was his work on kidneys. He was able to use his 3-D printer to create a kidney. The technology is in its early days. For example the kidney he made were prone to thrombosis and they could keep them alive for only 3 days. But during those days the kidney produced urine. He showed some biopsies of the kidneys he made and the audience gasped because they looked just like normal kidney biopsies. It was breath taking.
What an inspiring way to kick off Kidney Week. I think Pascale Lane summarized the mood of the conference hall as Atala finished:
Frankly organ regeneration has progressed waaaay farther than I thought. #kidneywk13—
Pascale Lane (@PHLane) November 07, 2013
Post written by Dr. Joel Topf, eAJKD Advisory Board member.
Check out all of the eAJKD coverage of ASN’s Kidney Week 2013!