Scientists have used tissue engineering techniques to completely replace penile erectile tissue in animals in a laboratory.
Researchers at Wake Forest University say that their breakthrough work could one day result in surgeons reconstructing and restoring function to damaged or diseased penile tissue in humans.
They were able to use cells from rabbits to grow replacement penile erectile tissue for the animals in the laboratory. After implantation with the replacement tissue, the rabbits had normal sexual function and produced offspring. This is the most complete replacement of functional penile erectile tissue reported to date.
“Further studies are required, of course, but our results are encouraging and suggest that the technology has considerable potential for patients who need penile reconstruction,” said Anthony Atala, M.D., institute director.
“Our hope is that patients with congenital abnormalities, penile cancer, traumatic injury and some cases of erectile dysfunction will benefit from this technology in the future.”
Reconstructing damaged or diseased penile erectile tissue has traditionally been a challenge because of the tissue’s unique structure and complex function. There is no replacement for this tissue that allows for normal sexual function. Various surgeries have been attempted, often multi-stage procedures that can involve a silicone penile prosthesis, but natural erectile function is generally not restored.
The scientists set out to solve this problem by working to engineer replacement erectile tissue in the lab. They first harvested smooth muscle cells and endothelial cells, the same type of cells that line blood vessels, from the animals’ erectile tissue. These cells were multiplied in the laboratory.
Using a two-step process, the cells were injected into a three-dimensional scaffold that provided support while the cells developed. As early as one month after implanting the scaffold in the animal’s penis, organised tissue with vessel structures began to form.
The erectile tissue the scientists engineered is known as the corpora cavernosa penis. Two columns of this sponge-like tissue form a significant part of the penis. These structures, which are bound together with connective tissue and covered with skin, fill with blood during erection.
The results were reported in the online edition of the Proceedings of the National Academy of Sciences journal.