Some day soon, you'll be able to take your grandma to the hospital for her cataracts and take her home with a new pair of eyes. Your old liver may be all partied out, but you'll be able to get a new one. Transplant surgery will be all the rage, with no waiting lists, no donors, no blood-typing, no side effects, and best of all, no rejection medicines. Why? Because the bioengineers will make the replacement organ out of your own body.
The main reason transplants fail is rejection; the immune system recognizes the foreign organ as an invader and attacks. The attacks are swift and final, usually causing severe complications within hours or days, depending upon the organ. Without immune suppression, a transplant patient risks death. If rejection occurs, a new organ must be procured in short order, but even that medical regimen causes its own, possibly fatal, side effects. The solution? Provide organs derived from one's own genetic material.
That's why the future of transplant medicine is stem cell autotransplantation, a process where organs grown from a patient's cloned tissue are transplanted back into the patient. It's still part theory, but it's based on working models that are used in conjunction with chemotherapy and treatment of blood disorders. In one experimental cancer treatment, doctors remove marrow or blood, and extract the stem cells. The cells are then returned to the patient in hopes of re-propagating the blood system with healthy cells. The procedure is still very new and is only used as a last-case scenario. So far, the success rates of re-propagation are questionable, but the possibilities are far-reaching.
The hottest ticket of late has been embryonic stem cell research, with scientists believing that only these nascent cells are capable of developing into any one of the different tissues of the body. Research is problematic, however. Most first-world governments don't allow public funding for human embryonic stem cell research because of ethical questions that surround the acquisition of embryos; the cells are generally derived from aborted fetal tissue.
An alternative has been proposed by the Scots at the Roslin Institute in Edinburgh, famous for the cloning of Dolly the sheep. They want to create a national tissue bank filled with samples from newborns that can be frozen until needed, then grown into any organ and transplanted back into the donor. Using the same cloning technology that created Dolly, the nucleus of one cell is injected into a stem cell that has had its nucleus removed. Then it's chemically induced to grow into whatever type of cell the scientists have engineered.
However, recent findings by scientists at NeuroSpheres Ltd. of Calgary, Canada, may divert attention from embryonic stem cell research. NeuroSpheres recently completed a study of neural stem cell generation in mice which suggests that adult stem cells may also be altered to behave as if they were embryonic stem cells. In essence, scientists may shortly be able to reprogram cells from adult tissue, making the use of embryonic tissue seem superfluous, if not barbaric.
Other transplant scientists are working to identify and manipulate the protein strands that cause rejection of organs in xenotransplantation (cross-species) and allotransplantation (from one person to another). Doctors hope to be able to put a pig liver in a patient, with no need for daily medication, by masking the cells of the transplanted organs with a lining of bioengineered cells. Cloning would aid the process by allowing geneticists to create one pig with the appropriate proteins that they would simply clone infinitely, making a warehouse of organs for sickly humans.
Organogenesis of Canton, Massachusetts, is involved in creating an extra-corporeal bioengineered liver: a combination of chemicals, enzymes, and a beef liver. Patients could attach themselves to the bio-liver machine once a day to replace or boost their own liver processes. The idea is not to replace transplant surgery, but to extend the life of those on the list waiting for a donor. Clinical trials should arrive in the next few years, but don't expect to see the machine in the local bar anytime soon.
Of course, even cloned xenotransplantation has received mixed reviews. While those on the waiting list are excited by the possibilities, the Animal Legal Defense Fund isn't having any of it. ALDF President Steve Ann Chambers states, "Cloning is merely the latest, most distasteful development in the long human tradition of converting 'lower animals' into utilitarian objects."
It may not matter. The stem cell autotransplantation technique remains the forerunner in organ transplant medicine. In fact, organs grown from stem cells would be healthier than the patient's original organs. The new organ would not have been subjected to the rigors of life, such as smoking, drinking, playing rugby, and eating fast food.
The throw-away society that gives us $100 VCRs and computer upgrades every six months may have finally caught on to our real needs, throw-away organs. Will the availability of new, healthy organs inspire irresponsible behavior? I can only answer on my own behalf. Yes!
Ryan McLaughlin makes a living as a research subject for clinical trials of a variety of psychotropic pharmaceuticals.