Sir Salty

Also could anyone explain why pancreas transplantation is rare and only occurs in patients with advance kidney disease? Why aren't many cases of diabeties 1 being cured by organ transplantation? I understand the risks involved with immunosuppressants, is this the only reason and if so do immunosuppressants have more severe side effects on diabetics? If not then what are the other limitations preventing allotransplantation from being a common practice to cure diabeties? If someone could respond as soon as possible as my paper is due on Wednesday. And could any information be linked with sources, thanks.

Hey, So for a essay I am writing I am discussing allotransplantation and its limitations and how xenotransplantation could potentially solve them. One limitation with allotransplantation is risk of infection due to exposure of donor/organ to the environment before the organ is transplanted. Another, of course, is side effects of immunosuppressants. I was wondering if anyone knows any sources where I can find data on which is more responsible for disease/infection after the transplant. I.e. how much does immunosupressants contribute and how much does epidemical reasons contribute? This would support that there are severe limits to allotransplantation however the screening of the animals and growing them in a controlled, sterile environment can help overcome risk of disease or infections as a result of the transplantation. Thanks, any relevant information, links etc would be much appreciated. Or any key terms or technical phrases which could help me locate the information. Also being very curious after writing 5000 words on the subject, what do you guys think about xenotransplantation specifically with "mixed chimerism"?

Go look up so details on CRISPR-cas9, thats whats currently being used to genetically modify the animals. Also go read the BBC news article I posted in OP and perhaps its references. It is not quite as simple as randomly mixing DNA, and there is already clear scientific proof that the human DNA interacted with the animal DNA which was why it was so successful and got published.

Yes agreed, however, to get to that stage is sorta trial and error. Therefore, a crude way to put it, at first it will be scientists mixing human DNA with animal DNA and allowing a creature with both to develop to a certain stage and observing results. Also the human cells theoretically will differentiate into only the animal organ the has been genetically removed, however some human stem cells may also become other cells. Also no medical reason to grow human brains inside an animal ^^ but yes that would definately cause ethical issues aha.

What you are saying is correct, theoretically, as long as the antigens present on the surface are removed and the structure is similar enough then it should be accepted, atleast with immunosuppressants. Therefore another method being studied is xenotransplantation, the transplantation of an animal organ (genetically modified perhaps but still considered that animal). However I am discussing a similar, although different process which has different applications. I would be a lot less hesitant to say that xenotransplantation is ethical, however with chimeras you are creating a hybrid creature, part human part another animal, possibly multiple animals. So perhaps the creature is only partially human, however at which point is it too human to be considered unethical (remeber we are growing this creature specifically to be killed), of course very subjective, which is why I want to hear others' opinions. And some would argue that mixing any human DNA with another animal is completely unethical. Also I would like to say that according to my knowledge, correct me if I'm wrong, the organ itself will be purely human, atleast the important parts including the surface antigens will be. This is because the blastocyst of the host animal is genetically modified so it cannot grow let's say a pancreas. Therefore when the human stem cells are implated at a very early stage, they human stem cells differentiate into the pancreas. Alot of research is being done looking into other medical applications such as using stem cells to heal people with parkinson's disease, I would recommend looking into it.

Because by changing that percentage by even 1% is already the difference between 2 completely different organisms. Therefore who knows what the resultant organism would be like. Perhaps in the future we would be able to control precisely what the animal would be like, which would be the aim of the research of course so that scientists can develop perhaps a sheep with a human pancreas to harvest. However to get to that point first a "creature" containing both human DNA and in this case sheep DNA would have to be allowed to develop experimentally without knowing exactly what the outcome is. Futhermore theoretically, say that we do get to the stage where we can grow a sheep that has a human pancreas. Why not for increase in efficiency also have that same sheep grow human lungs and heart. However is the organism still a sheep or has it become more human? Therefore we will eventually get to a point where we are growing creatures which resemble humans more than anything else and killing them.

To clarify I do understand that there are many ethical questions that can be asked of this procedure and therefore would like to mainly focus on 1) the use of embryonic stem cells, and 2) is it ethical to create human chimeras. In the 2nd point I'm more interested in how we should go about creating and allowing such a creature to develop as it would not only be against many religous beliefs, but also if we should consider it different from any other animal which is non-human. However feel free to discuss everything relating to the topic as it is all fascinating. I would like to add in response to those mentioning the potential danger of them escaping and spreading mutations that it is highly unlikely that they could even reproduce similarly to how mules cannot reproduce (please correct me on this if I am wrong). However the reason I assume this is because the human stem cells would be transplanted into the embryo of the creature and so human DNA would be part of the animal as it grows up. Also they would very likely have to be carefully contained in laboratory like conditions anyways in order to make sure they are protected from all disease or infection. Of course this would fall under regulations which are considered humane for the animals. This would reduce the risk of the escaping to near nought especially considering that they would be harvested around the time or slightly before the become mature enough to reproduce because it is at that same time the animal is the right size and the organ is fully developed. However this is all theoretical and would greatly depend on the animal being used.

Hey all I am a student studying A'levels and this is my first post. Recently I have been reading up about the usage of stem cells in research and some of the ethical issues that come with it. In this thread I specifically want to discuss whether using stem cells to create human chimeras is an ethical practice. This involves taking stem cells (models have successfully used IPSCs) to create a chimera; a hybrid of a creature. The purpose of this would be to grow human organs within another creature which could then be harvested and transplanted into a human potentially solving the current organ supply crisis. Of course there are still many limitations before it becomes a reality, however the research is taking place and more can be read about it in detail in a science article BBC recently posted: http://www.bbc.com/news/health-38717930. I am very curious as to what people think about this research and the ethics behind it, mainly focusing on: 1) Is it ethical to use embryotic pluripotent stem cells (although in this case there has been some success with IPSCs). 2) Is it ethical to create human chimeras, or perhaps better to ask, to what extent should we allow these organisms to develop before understand what they really are. I am currently quite open-minded about this and would like strong arguements from both sides to be presented. For the sake of arguement and getting a deeper understanding I will try my best to actively argue and throw out points to consider from both sides of the arguement. Please keep in mind that it is my first thread and I am only an A'level student so forgive my ignorance in some areas especially if I need additional explanation. Cheers, Sir Salty.