Pig-human chimeras: a clinical trial announced in Japan

 

    In an article published in 2019 on Bioethics Press Synthesis, Henrianne introduced one of the new advancements in biology and the medical field, but it is also one of the most controversial experiments in recent years. 

    In this era, there is a high demand for organ transplants. In the past, the organs were mostly from human donors. But as science becomes more advanced, we have found ways to use organs from animals to transplant for those in need, rather than waiting for a donor, which is very rare. In 2019, a Japanese researcher, Hiromitsu Nakauchi, announced his new experiment in Japan to culture human pancreas in pigs. This was proposed soon after Japan had relaxed its chimera law. 

    In this experiment, he planned to inject human induced pluripotent stem cells into genetically modified pig embryos. The result after these cells are injected was described as: 

"These iPS cells will take the place of the removed gene in the embryos to create a human pancreas. The chimera embryo will then be implanted into a carrier sow’s uterus. The foetus will be removed before birth to study how much pancreatic tissue is derived from human iPS cells and how it functions." (Pontbriand, 2019). 

This is a big advancement in the study of chimeras. But at this time, these animal-human chimera embryos can only be implanted into animals; implanting chimeric embryos into humans is still prohibited. 

WORKS CITED

Pontbriand, H. D. (2019). Pig-human chimeras: a clinical trial announced in Japan. Bioethics News. https://bioethics-news.com/2019/05/13/pig-human-chimeras-a-clinical-trial-announced-in-japan/

Raposo, V. L. (2021). The new Japanese regulation on human/non-human chimeras: should we worry? National Library of Medicine. https://pmc.ncbi.nlm.nih.gov/articles/PMC7863089/

When a DNA Test Says You’re a Younger Man, Who Lives 5,000 Miles Away

A patient by the name of Chris Long received a bone marrow transplant four years ago and has discovered that his DNA has been replaced by his donor’s DNA. Even the DNA in his semen had been replaced by the DNA of his donor’s. Now Chris long is referred to as chimera, a person with two sets of DNA. This is very rare and sparks an interest for crime investigators. If Chris Long were a victim or perpetrator investigators would have the DNA of his donor’s instead of his, throwing off the whole case. Even though Chris now has the DNA of his donor’s his brain and personality should remain the same. Where his DNA is going is unimportant to his doctors but not to forensic scientists. A person who is Chimera can commit a crime and mislead crime investigators. 

Links:

https://www.nytimes.com/2019/12/07/us/dna-bone-marrow-transplant-crime-lab.html 

https://www.scientificamerican.com/article/3-human-chimeras-that-already-exist/ 

Human-Pig Hybrid

Scientists have recently discovered two ways to create hybrid "human-animals" that have the potential to save thousands of people every year. The feat that has been accomplished is that an organism has been created that contains cells from two separate species. Just like when humans receive transplants, one way to do this is to introduce the organs from an organism of one species into an organism of another species. However, like human to human transplants, those organs could be rejected by the recipients immune system. The more advanced process they have been able to come up with is introducing cells from one species into the embryo of another species, thus allowing them to grow together, avoiding rejection.

Pigs are very similar to humans, so the outlook for this medical advance is certainly promising. In this study, when the human cells were introduced into the pig, it was critical that the timing was perfect, as improper timing lead to fatal results for the pigs. This will take some time to perfect, and if these cells were introduced into humans as of right now, it would likely fail. However, if they could increase the number of human cells that the pig embryo could tolerate, this experiment would be much more successful.

Though this research is extremely controversial, I would have to admit that I think the ethical concerns are well worth the risk. It upsets some people that scientists are creating hybrids and combining humans with animals because it is, after all, quite strange and foreign. However, the results would be beneficial to all of mankind. Thousands of human lives could be saved each year by growing organs from these chimeras. Overall, if the process can be perfected, it will be well worth it.

http://news.nationalgeographic.com/2017/01/human-pig-hybrid-embryo-chimera-organs-health-science/

http://www.sciencealert.com/it-s-alive-the-first-human-pig-hybrid-has-been-created-in-the-lab

Human-Pig Hybrid Chimera Study

Scientists have created more than 2,000 human-pig hybrids in the hopes of using the information gained to one day grow human organs inside of animals for transplants. The hybrid embryos were allowed to develop to 28 days before being removed. This short time frame allowed scientists to see how the human and pig cells mix together.The study has come under fire as ethical concerns from the US National Institutes of Health had put a temporary  ban on funding for this controversial experiment last year.  One ethical concern brought about during the ban was that hybrid creatures could theoretically have humanized brains,  and what that could mean if they were accidentally released into the wild. Although i understand the ethical dilemma faced with chimera research I feel as though there is many advantages that this research could bring that cannot be ignored. Not only is this study bringing us closer to understanding how different cells can interact it also allows us to learn the information that can one day lead us able to grow human organs ready for transplant.

https://www.theguardian.com/science/2017/jan/26/first-human-pig-chimera-created-in-milestone-study
http://www.counselheal.com/articles/31719/20170130/human-pig-chimera-embryo-development-grow-donor-organs.htm

Scientists take first steps to growing human organs in pigs

http://www.pressofatlanticcity.com/news/ap/scientists-take-first-steps-to-growing-human-organs-in-pigs/article_edb4e1bd-7055-54d9-bac2-6e4eb93c4f3e.html

https://www.ncbi.nlm.nih.gov/pubmed/15454959

In this article, scientists took the next step forward in genetics. Malcolm Ritter wrote about how human cells have been placed inside the embryos of pigs. These types of animals with cells from different species are called chimeras. The injected human stem cells in the pigs are projected to be the first step towards growing livers, hearts, pancreases, and other human organs. The researchers believe this will ease the shortage of human donors for transplants. As the pigs grow the human organs will grow in place of their own. Once the organs are ready to be removed, the pigs will be euthanized. Even though such mixing has been done on rats and mice before, this type of  human-animal research has raised ethical concerns in the science world.

My older brother came to me with this article in the Atlantic City Press. This type of information sounds so futuristic and bizarre to me. I have heard of people using pig valves for heart repairs, but never would I think of using pigs to harvest human organs. This is an amazing revolution for doctors and transplant patients. This will most definitely be up for ethical discussions among certain individuals, but I believe this will save the lives of many.

A Pregnancy Souvenir: Cells That Are Not Your Own

A team of pathologists at Leiden University Medical Center in the Netherlands found that chromosomes from a growing fetus venture off into the mother's body and into many different organs and tissues.  

It was easier to distinguish this in mothers bearing sons because the chromosome that distinguishes males from females is the Y chromosome (male sex chromosome).  

The pathologists started by collecting tissue from 26 women who had died during or after giving birth to their male babies.  It was found that there were Y chromosomes found in every tissue sample taken!(brains, hearts, kidneys, etc.)

This phenomenon was linked to fetal microchimerism, identified in the 1990s by scientists that found that cells from both sons and daughters could leave through the uterus and into many different cells of the body.  This name is derived from the Greek mythology monster, Chimera, that was a goat, lion and dragon all at once.

Recent studies suggest that women always acquire fetal cells each time they become pregnant and these cells can linger in her system for a long time or can eventually disappear.  It is controversial whether or not these cells can be beneficial or harmful to an expecting mother because of the different studies done and what beneficial and hindering effects pregnancy may have on a mother (better healing abilities, postpartum depression or even cancer?).  

More studies will develop over time to better understand the significance of fetal cells in pregnant mothers

I think this is so interesting.  Who would have known that male chromosomes could be swimming around in a mother during and after her pregnancy?  It probably would have been detected sooner but it is easier to distinguish the Y chromosome of a son in the body of a female as opposed to an X chromosome in a female from an unborn daughter.

To read the full article click here or here