In a scenario somewhat reminiscent of Frankenstein and his creator, scientists have found themselves able to can create chimeras – Creatures that have the body parts from other species working inside them – by injecting stem cells into the embryo from one species to another, beginning with injecting rat stem cells into mouse embryos, genetically altered to block production of their own organs, creating mice with rat organs inside them.
The presumption is, of course, that these techniques could be employed to allow human organs from patient’s stem cells, for use as transplants to order, to be grown within the bodies of pigs reared specifically for that purpose, helping nullify rejection risks as well as providing an abundance of donor organs for others, a godsend when you consider that current organ shortages mean patients enduring long transplant waiting times at the present.
Director of the University of Tokyo centre for stem cell biology and regenerative medicine, Professor Hiromitsu Nakauchi stated that the so-called blastocyst complementation should see functional human organs being createdusing this approach in the near future, when presenting his findings at the annual conference of the European Society of Human Genetics.
He stated that adult stem cells, known as induced pluripotent stem cells, can be taken from, for example the skin, being then encouraged to develop into any type of body cell. These cells taken from rats had been injected into the blastocysts, of mice, unable to develop a pancreas, the organ that produces important hormones including insulin for themselves.
On reaching adult status, the treated mice showed no diabetic signs, having developed rat stem-cell induced pancreas, the researchers believing that almost any organ could be produced in this way, so they hope to do the same using pigs and also seeking permission to use human stem cells for experimentation
There has already been some success in the use of pigs for medical purposes, with pigs becoming able to generate human blood by having blood stem cells from humans injected into the pig foetuses very early in thier development. Ther future is very definitely looking much more hopeful for those unfortunates in need of transplants, though there is still some way to go yet
Happily, the Roman Catholic Church has stated that such Chimera embryos should be regarded as human, the mothers allowed to give birth to them, and to raise them as their own children if they wished, not seeing any reason why why interspecies embryos should be treated any differently.
There are of course those for whom the mythical creature that was half man and half animal, the Chimera, should never be allowed to grow within a woman’s womb, but this breakthrough should be hailed as a major step forward in medical research, and the doubters should think about how they might see it if the person in need of a transplant were themselves.