siRNA in vivo?? - (Dec/01/2004 )

Hi!! I'd like to use siRNA in vivo in rat brain and i would like to know if sombody start to use it in vivo. I'm sorry for my english...jeje thanks

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siRNA has been used in mouse in vivo using a hydrodynamic tail vein injection technique. I am not sure if siRNA has been used in Rats or if siRNA can reach the brain.

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Hi Raul,

I too am interested in targeting the brain, however I think this will be very difficult. Please anyone correct me if I'm wrong, but I think the only way to do this would be to have a promoter that is brain-specific. The problem is that we also need a promoter that will produce functional siRNA (ie a polIII promoter). I do not know of a polIII promoter that is brain specific and I cannot think of another way around this.

Regarding you using rats, I am told that transgenic animals are always mice - though I'm not sure if this is due to a biological reason or an historical one - I'm hoping someone else will know why this is??

cat

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Hi again,
I take back what I said previously! If you look at the paper by Thakker et al in PNAS, Dec 7 2004 vol 101 (49), they have infused siRNA into the vetricles of the brain and have knocked down genes in the surrounding tissue - it is not targeted evenly throughout the whole brain, but it might work depending on what you're looking at.
Good luck!
cat

Neurochemical and behavioral consequences of widespread gene knockdown in the adult mouse brain by using nonviral RNA interference.
http://www.ncbi.nlm.nih.gov/entrez/query.f...t_uids=15569935

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Hi Raul,
Please have a look on this article :
siRNA-mediated gene silencing in vitro and in vivo

Haibin Xia, Qinwen Mao, Henry L Paulson, Beverly L Davidson
SUMMARY: RNA interference is now established as an important biological strategy for gene silencing, but its application to mammalian cells has been limited by nonspecific...
CONTEXT: ...by small interfering RNA (siRNA) is now recognized as a naturally occurring biological strategy for silencing alleles during development in plants, invertebrates, and vertebrates. In mammalian cell culture, siRNA-mediated reduction......
Nature Biotechnology20, 1006 - 1010 (01 Oct 2002) Research

Bye

Eric

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hi
you're right siRNA have been used in vivo.
You can read the papers from emily berstein and also a good recent paper which tells about the clearance of hepatitis virus (i don't remember at time the title).

You can try. Tell me please if you succeed.

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We have done some studies with local CNS administration of siRNA using unique polymer transfection reagents from Intradigm Corporation (unfortunately only available by collaboration). The results look good for our target tissue. Intradigm can be contacted at 301-984-0185.
If you have found other good reagents for local administration please let me know.

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Hi, I am interested in the siRNA in vivo too, as I know, PEI is the most promising carrier which can make the siRNA stable in vivo. Several groups had done successfully. We R preparing to do.
PEI is available from PolyPlus Transfection.

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