stem cells from skin cells.

[cameron marical]

http://www.nytimes.com/2007/11/21/science/21stem.html?_r=1&em&ex=1195966800&en=09f92cd386d8ea6e&ei=5087%0A

 

here is a link to the article i read that talked about how 2 teams of scientists were able to create stem cells from skin cells. it talks about how they use a retrovirus to insert 4 genes into the nucleas essentially blanking the slate of the skin cells and making them stem cells. it doesnt really go into the process much from what i read. does anyone know how this could work? why is this not big now? it was posted in 2007 so i dont know whats happened with this research since then, is there a roadblock or something? i also just thought that its very interesting.

 

thanks.

[luminogenics]

Yes the proteins are for transcription factor that activate genes that would otherwise be dormant in a differentiated cell.

Edited April 26, 2009 by Sayonara³

[crazybrain68]

A major problem they have had was that of the genes used, I believe at least one was an oncogene if I remember correctly, so many of the cells turned cancerous. Recently though they have been able to convert adult cells to an embryonic stem cell like state without using these genes. If I remember correctly one method used plasmids (not sure though), and I recently heard of another method where they used certain proteins, though I haven't heard much about that, just saw one story and they were not clear about what the scientists actually did.

[cameron marical]

How exactly does the embryo create stem cells?

 

Could we replicate a stem cell protoplasm artificially and then insert ones dna into the nucleolus of it?

 

Kind of off topic:

Does dna contain all of the information to create any type of cell? what about the mitochondrian? does it know how to create that and the dna inside of it?

 

ES stem cells are the best right? becuase their totipotent?

 

Thanks.

Edited April 27, 2009 by cameron marical

[crazybrain68]

Stem cells arise naturally in the development of humans (and many other animals), they are extracted from the inner cell mass of a blastocyst. As for your second question it sounds like you might be describing therapeutic cloning?

 

Yes DNA (from a nucleus) does contain all the information necessary to make a cell, the mitochondria only contains mitochondrial DNA and only codes for more mitochondria (I think).

 

As for if ES cells are the "best", from my understanding that is not an easy question to answer because both ES cells and adult stem cells have their own advantages. You are correct in saying that ES cells have the highest capacity for differentiation.

[cameron marical]

ok, thanks.

 

how does the mitochondrian replicate at the same time as the cell in mitosis? does it?

 

what are the advantages of adult stem cells?

 

thanks for your answers.

[crazybrain68]

Mitochondria do replicate during mitosis, however I do not know any specifics of the actual process, if you want to know more on the specifics of the process I suggest looking through a cell biology text or asking a professor/teacher. The main advantage I remember offhand for adult stem cells is that since when used in treatment they are often taken from the patient, they dont have a problem with tissue rejection.

 

Also most stem cell treatments currently in use utilize adult stem cells if I am not mistaken. The last I heard there was at least one embryonic stem cell treatment in clinical trials. I will try and see if I can find the article where I read that for you.

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Just a heads up for you cameron, but there is a pretty decent article in the May issue of Scientific American on tissue engineering and the roles of various stem cells play in the engineering of tissues.

[lucaspa]

http://www.nytimes.com/2007/11/21/science/21stem.html?_r=1&em&ex=1195966800&en=09f92cd386d8ea6e&ei=5087%0A

 

here is a link to the article i read that talked about how 2 teams of scientists were able to create stem cells from skin cells. it talks about how they use a retrovirus to insert 4 genes into the nucleas essentially blanking the slate of the skin cells and making them stem cells. it doesnt really go into the process much from what i read. does anyone know how this could work? why is this not big now? it was posted in 2007 so i dont know whats happened with this research since then, is there a roadblock or something? i also just thought that its very interesting.

 

thanks.

 

This is very big now. The cells are called "induced pluripotent stem cells" or IPS for short. There are a huge number of laboratories doing this now and investigating the use of IPS cells for regenerative medicine. Do a PubMed search on "induced, pluripotent, stem, cells" and you will get a lot of articles.

 

If you want the original methods paper on how to do this, I have the PDF file and can attach it.

 

There is a hitch, however. At least one of the genes transduced into the skin cells to turn them into embryonic stem cells is an oncogene -- a gene associated with cancers. So there is concern that the IPS cells might become cancerous if implanted into a human.

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ok, thanks.

 

how does the mitochondrian replicate at the same time as the cell in mitosis? does it?

 

what are the advantages of adult stem cells?

 

thanks for your answers.

 

The mitochondria replicates separately from the cell. During mitosis the cytoplasm simply splits up the mitochondria that are in it.

 

Embryonic stem cells have 3 major problems:

1. If implanted en masse in a body, they form a type of tumor called a "teratoma".

2. Because they do not come from the individual being treated, the ES cells can cause an immune rejection response.

3. They differentiate willy-nilly into all the phenotypes. That's why they make a teratoma in vivo.

 

Adult stem cells have several advantages:

1. They can come from your own body, thus no immune rejection.

2. They seem to modulate the immune response and it looks like we can use adult stem cells from another person to treat you.

3. They do not form teratomas when implanted en masse, so you can use them for large defects in tissue, like defects in cartilage in osteoarthritis.

4. They remain undifferentiated until they receive a specific signal to differentiate. Thus, once we find specific differentiation signals, we can differentiate the cells outside the body to form a tissue (such as a bone) and then implant the completed tissue.

5. There are no ethical concerns about adult stem cells.

[cameron marical]

The mitochondria replicates separately from the cell. During mitosis the cytoplasm simply splits up the mitochondria that are in it.

 

After mitosis and the mitochondria are seperated, do they repair themselves or anything along those lines? Would the cells eventually run out of mitochondria after several mitosis cycles?

 

Thanks for the info on all this stuff. I would love to have the pdf file, but my computer seems uncooperative with pdf files for some reason and I can never open them up. Is it available on the web anywhere?

 

Thanks.