As a science, tissue engineering has been around for more than 20 years. Many recall the infamous Vacanti Mouse of 1997 – an early effort that sparked a media circus as it involved an unfortunate hairless mouse with a human ear grafted jauntily onto its back.
While the Vacanti Mouse might seem slightly ghoulish, the goal of tissue engineering is noble. The dream that researchers have doggedly pursued is the capacity to grow whole organs in the laboratory – hearts, lungs, livers and the like which could save countless lives.
In the years since the Vacanti Mouse, there have been astronomical leaps in the technology and scientific know-how related to tissue engineering and the tireless research is starting to bear fruit. A pilot study was recently published in the journal The Lancet on April 11 in which four women successfully received laboratory-grown vaginas.
The study selected four women between the ages of 13 and 18 who suffered from a genetic disorder known as Mayer-Rokitansky-Küster-Hauser Syndrome, or MRKH.
According to the National Institute of Health webpage on MRKH, the syndrome “is a disorder that occurs in females and mainly affects the reproductive system.”
The disease has a somewhat murky genetic link and is thought to be influenced by environmental factors during fetal development. “This condition,” according to the National Institute of health, “causes the vagina and uterus to be underdeveloped or absent.”
The four patients were treated by a collaborative team of Mexican researchers from the Federico Gomez Children’s Hospital in Mexico City and American scientists from Wake Forrest University.
According to The Lancet, the vaginal implantation was a three-step process. The first step was culturing vaginal cells from the patients. This was done by taking a small sample of tissue from the vagina – “less than half the size of a postage stamp,” according to a Scientific American article about the procedure – and then allowing the cells to replicate in a lab.
Once cell numbers were sufficient, it was time for step two. The proliferated cells were “seeded,” or spread across a special “scaffold” structure. According to the Scientific American piece, muscle cells were placed on one side of the scaffold and epithelial cells on the other to mimic the natural structure of the vagina. The fabric-like scaffold provides structure for the cells to grow on and then harmlessly degrades inside the body.
“We were able to shape the scaffold specifically for each patient,” Dr. Anthony Atala told Scientific American, “and place this device with the cells in a bioreactor — which is an oven-like device and has the same conditions as the human body — for about a week, until it was slightly more mature.”
Step three was surgical implantation of the lab-grown organs. According to Scientific American, “Once the organs were ready, doctors surgically created a cavity in the patients’ bodies, and stitched one side of the vaginal organ to the opening of the cavity and the other side to the uterus.”
The earliest of these surgical implantations happened eight years ago, and the research team has spent the interim closely monitoring their patients.
Yearly biopsies and MRIs have found “no long-term postoperative surgical complications,” according to The Lancet. Self-administered “Female Sexual Function Index” surveys of the implant recipients indicate that factors such as desire, arousal, orgasm and painless intercourse are all within normal ranges. Because the vaginas were constructed from cells native to their host bodies, there was no danger of organ rejection by the immune system.
For all intents and purposes, the four cases described in this pilot study appear to be unqualified successes.
The same research group was also successful at re-growing cartilage in the noses of patients suffering from facial cancer, but the real victory was the growth and implantation of such a complex sex organ.
Though this is only a pilot study – with a meager four cases for comparison – it is nonetheless encouraging. Tissue engineering has come a long way since 1997, and it may be only a matter of time before a wide variety of lab-grown organs become available.
