In 2008, a Spanish woman with tuberculosis received a windpipe transplant. Of course, the trachea Claudia Castillo received was not her own. Amazingly though, the cells inside the transplant organ’s structure were.
A similar procedure to manufacture human organs was successfully achieved for nine people in need of bladder transplants:
Scientists in Barcelona and at Wake Forest University successfully cultured adult stem cells from their respective patients bone marrow and the target tissues (trachea and bladder, respectively). This much is not a revelation. But instead of culturing cells in a petry dish, the stem cells were cultured of the extracellular matrix or “scaffold” of transplanted organs.
Using detergent agents, cells can easily be washed from the collagenous scaffold present in all organs. Below is a stepwise exhibit of “washing” of a rat’s heart. On top you see an “out with the old” cells progression. On the bottom, there are new cells being cultured in the scaffold.
Electrophysiological signals can be transmitted through the new organs, and because the cells are those of the patient, the organs will not be rejected upon transplanting.
Another form of ex vivo organ generation, often called 3-D bio-printing, has also caught the imagination of the biomedical world. This time, no scaffold is needed from an organ donor.
The “ink” in the bio-printing process is composed of spheres packed with tens of thousands of human cells from the patient. These spheres are assembled or “printed” on sheets of organic biopaper which will degrade after the cells adhere to each other in a 3-D structure. Layer by layer, the bio-printer can build an organ from scratch!
Scientists from Moscow to Melbourne to Missouri are forging ahead with this new technology. While still experimental, transplant of small sections of “bio-printed” cardiac artery have been successfully transplanted.
Dr. Gabor Forgacs at Missouri University is a pioneer in the field. “You give us your cells: we grow them, we print them, the structure forms and we are ready to go,” he says. “I am pretty sure that full organs will be on the market [one day].”
Sometimes, scientists adapt an actual printer to lay down the human cells and grow them in 3-D! Such as at Wake Forest: