Talk:Induced stem cells
Initial comments Edit
This page has moved from Wikipedia:Induced stem cells to Wikiversity:Induced stem cells as all of the Wikipedia content must be supported by secondary sources, as per WP:RS. "We need to wait until all cited articles will be discussed in secondary sources". But, the article Induced stem cells most fundamentally relies on primary sources, where WP calls for primary reliance on secondaries. At the same time instructional and study guides that make use of original research are allowed on Wikiversity. Furthermore, Wikiversity will offer a space not just for hosting research, but also for facilitating research through creating researcher communities. Wikiversity is the place for original research, including primary or secondary research. This includes interpreting primary sources, forming ideas, or taking observations. See Wikiversity:What is Wikiversity?# Wikiversity for researching. I'll be grateful to everyone who will help me to pursue further issue which will not be built on "second-hand". I apologize for my bad English. Dmitry Dzhagarov (discuss) 10:08, 12 May 2014 (UTC)
- @Dmitry Dzhagarov: Wikiversity encourages participants to teach, study, research, and learn about things, which is very different from an encyclopedia like Wikipedia. I think the presentation should reflect that difference. If this resource is meant to present the latest research about induced stem cells from primary sources, the resource may benefit from like a brief one or two paragraph mention of what induced stem cells are with a reference to Wikipedia for participants to gain a general understanding, and the rest of the resource can focus on helping participants to learn more about induced stem cells by explaining any research published in primary sources. Another approach may be to contrast the differences between the latest research findings with what is presented in secondary sources like Wikipedia. Additionally participants may benefit from a presentation style that breaks up the topic into many separate lessons across multiple subpages, for example "Induced stem cells/Blood" or "Induced stem cells/Cancer risks". -- darklama 14:11, 12 May 2014 (UTC)
Induced stem cells vs embryonic stem cells lines obtained by SCNT (discussion) Edit
Discussion on The race to produce a cloned human embryo is over. What’s next? & Human cloning by nuclear transfer confirmed by Ariel Poliandri Science moves fast; last year a scientific article from Shoukhrat Mitalipov’s lab (see in resource) claimed that they had succeeded in cloning a human up to the stage of embryo and produced stem cells from it. I was sceptical back then and commented “Other labs still have to reproduce Mitalipov’s experiments…”. So far this year at least 3 labs ((see in resource)) have reproduced Mitalipov’s work: they have introduced the nuclei of adult cells into oocytes, produced embryos and generated embryonic stem cells from those embryos. This has been –in many ways- a big scientific breakthrough. Now a wider debate should take place to determine whether there is any need to continue producing more embryonic stem cells lines by this method.
Embryonic stem cells (ESCs) can be propagated almost indefinitely in culture and have the potential to differentiate into any one of the more than 200 cell types in the adult body. These properties make them an ideal tool for research and regenerative medicine. There are currently hundreds of embryonic stem cell lines that were generated from normal embryos. Extensive comparisons between normal ESCs and ESCs produced by cloning may be required to establish their equivalence. The exact number of cells produced by cloning that will be required for doing this is open to question.
In 2006 -before human cloning was achieved- a method was developed for generating embryonic-like stem cells directly from adult cells, without the need of using embryos (4). These cells are called iPSCs. We can produce iPSCs routinely now, through chemical or genetic manipulation of adult cells. Scientists have found that iPSCs are not exactly equivalent to ESCs. iPSCs show different marks that allow for their separation from true ESCs (5). But scientists have also shown (in several animal models) that iPSCs are capable of generating any organ in the body, including the sexual organs (Expand explanation). Hence, iPSCs can do pretty much everything ESCs do, regardless of “marks”. Too much emphasis on classifications by marks and fingerprints can be misleading if, at the end of the day, iPSCs act like ESCs.
For the moment, the weakest point of iPSCs is that they are generated mainly by genetic manipulation. This makes their approval for clinical use burdensome; there might be “off-target” effects rendering the cells prone to becoming cancerous. Cloned ESCs do not require genetic manipulation. On the other hand, cloned ESCs may also carry abnormalities, and their genetic material is not 100% identical to the DNA of the individual that was cloned -The mitochondrial DNA belongs to the oocyte’s donor.
There are many ethical problems regarding both human cloning and generation of embryos for medical or experimental purposes. Some countries, like Germany, have pre-emptively banned the creation –by any means- of embryos for research; in the UK there is no such a ban but funding for this type of research needs to be approved by an ethics committee (the Human Fertilisation and Embryology Authority or HFEA). In the US, after the 2009 repeal of regulations imposed during Bush’s administration, there seems not to be a clear framework regarding the creation of embryos (6). The existence of moral issues does not mean that the procedure should be banned outright. Many things that are morally questionable -like wars- are some times necessary. In the case of human cloning and embryo generation -as with war- there needs to be public consensus and general certainty that what we are doing has the right objectives and clear, achievable goals ̴̃ Paul Lucas 12/05/2014 at 8:33 pm The reasoning behind cloning from an adult cell was to circumvent immunorejection. Yes, there are dozens of ESC lines produced, but any tissues from them are, the thinking goes, going to have the immunogenic determinants of the embryo. Placing those ESCs, or tissues derived from them, into a person will set up a rejection response that is currently seen with organ transplants. The recipient would have to be on immunosuppresants for the rest of his/her life and susceptible to infection.
However, ESCs derived from an individual’s adult cell will have, so it is thought, the immunological determinants of that person. Thus any ESCs or tissues derived from them would be autologous (self) and not set off a rejection response. That is the main clinical driver behind the research.
Ariel Poliandri 12/05/2014 at 8:46 pm You make a good point Paul. Having an isogenic tissue is certainly a convenient feature for regenerative medicine. However -as mentioned in the post- cloned cells are not 100% isogenic. iPSCs can be generated by transient or permanent genetic modification; if produced by the former, they are 100% isogenic.
Accidental import merger and correction Edit
Apologies - I accidentally merged the en.wp page with this page on 31 May 2020. I've now corrected to revert to how it looked beforehand. Other content now at WikiJournal_Preprints/Induced_stem_cells. T.Shafee(Evo﹠Evo)talk 04:31, 12 June 2020 (UTC)