CYIL vol. 8 (2017)

CYIL 8 ȍ2017Ȏ REFLECTIONS OF ETHICAL DEBATE IN THE INTERNATIONAL LAW REGULATION … More generally, stem cells are cells with three basic characteristics: they are not terminally differentiated, they can divide with no limit and, after the division, each new cell may either stay a stem cell or undergo the process leading to terminal differentiation. In a laboratory environment, the stem cells live in populations called stem cell lines. These lines are cultured in vitro , keep their undifferentiated state and also keep their genetically normal state. There are basically three ways to obtain embryos for the purpose of their destruction and subsequent acquisition of ESCs. The researchers may use 1) the so-called surplus embryos which were created for the purpose of IVF ( in vitro fertilization , a very common assisted reproductive technology), 2) embryos created via IVF directly for the purpose of ESC research, or 3) embryos created via therapeutic cloning. We should further explain that while the technique of cloning is the same in both cases, the law (and also many ethicists) differentiates therapeutic cloning, in which the embryo is created only to be destroyed after several days for the purpose of research or medical use, and reproductive cloning, in which the embryo would be let to develop into a foetus and then to be born. While the former is legal in many countries, the latter is prohibited on the international level. It is now clear that the ASCs are much less suitable in biomedicine than the ESCs, mostly for the lesser variability of resulting specialized cells. In the early 2000s the possibilities of great medical innovations were associated only with the ESCs, fuelling a harsh discussion over the moral status of embryos. A certain change came in 2006 when the Japanese scientist Shinya Yamanaka and his team published in the journal Cell their study 3 proving that a specialized somatic cell from an adult person can be genetically returned to its pluripotent state, or, in other words, reprogrammed to become an induced pluripotent stem cell (iPSC). 4 During the last ten years, iPSCs have been increasingly improved 5 , but they still cannot fully replace the use of ESCs – and embryo-destructive methods – in the stem cell science 6 . 3 TAKAHASHI, Kazutoshi, YAMANAKA, Shinya. Induction of Pluripotent Stem Cells from Mouse Embryonic and Adult Fibroblast Cultures by Defined Factors. Cell. (2006, Vol. 126, No. 4), p. 663-676. accessed 4 March 2017. 4 For a very brief introduction to various types of stem cells, see ŠOLC, Martin. Právní aspekty výzkumu lidských kmenových buněk. In ŠUSTEK, Petr, HOLČAPEK, Tomáš (eds.), Zdravotnické právo. Wolters Kluwer, Praha 2016, p. 731-732. 5 See BAKER, Monya, Adult cells reprogrammed to pluripotency, without tumors. Nature Reports Stem Cells. (6 December 2007.) accessed 4 March 2017. CHOI, Jiho, LEE, Soohyun, MALLARD, William, CLEMENT, Kendell, TAGLIAZUCCHI, Guidantonio Malagoli, LIM, Hotae, CHOI, Young, FERRARI, Francesco, TSANKOV, Alexander M., POP, Ramona, LEE, Gabsang, RINN, John L, MEISSNER, Alexander, PARK, Peter J, HOCHEDLINGER, Konrad, A comparison of genetically matched cell lines reveals the equivalence of human iPSCs and ESCs. Nature Biotechnology. 2015, Vol. 33, No. 11, p. 1173-1181. accessed 4 March 2017. 6 See KIMMELMAN, Jonathan, HYUN, Insoo, BENVENISTY, Nissim, CAULFIELD, Timothy, HESLOP, Helen E., MURRY, Charles E., SIPP, Douglas, STUDER, Lorenz, SUGARMAN, Jeremy, DALEY, George Q., Policy: Global standards for stem-cell research. Nature. (12 May 2016.) accessed 13 March 2017. RAVVEN, Wallace. The Stem-Cell Revolution Is Coming – Slowly. A Conversation With Shinya Yamanaka. The New York Times. (16 January 2017.) accessed 13 March 2017. COOK, Michael, Is the great stem cell debate over? BioEdge. (31 October 2015.) accessed 4 March 2017.

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