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  #1  
Old 08-04-2012
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Default Find a good candidate for delivering this gene to neural tissues

Following approval by the Institutional Research Board for Human Subjects, a 30-year-old man diagnosed with Parkinson disease received a defective viral vector-tyrosine hydroxylase (TH) gene (8 kb) construct via stereotactic intracranial injections into the striatum. Monitoring of the patient showed persistent expression of TH and extracellular concentrations of dopamine. What vector is a good candidate for delivering this gene to neural tissues?

a) DNA packaged in a liposome
b) Modified adeno-associated virus (AAV)
c) Modified adenovirus
d) Modified herpes simplex virus (HSV)
e) Modified retrovirus
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Old 08-04-2012
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guess E......
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Old 08-05-2012
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Default correct answer

The answer is d) Modified herpes simplex virus (HSV)

It's sort of experimental-like question (at least to me
But I thought the concept was interesting. I was btw A and D bc I was looking for something that would be either neurotrophic or would cross the BBB. I excluded E bc I thought it would be too dangerous. But bc liposomes will not get into the nucleus D is the answer

Here's the official explanation:

HSV is a very attractive vector for infecting neuronal cells because it can incorporate large genes (up to 40-50 kb), it is neurotrophic, and it can establish latent infection in these cells. It can create an immunologic reaction, but antibody reactions are not severe. HSV does not integrate into the host genome, precluding long-term, stable expression, but this is being overcome with new HSV-AAV combination constructs.
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Old 08-07-2012
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hey where do you get this question from? its kinda hard
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Old 08-07-2012
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Quote:
Originally Posted by Casandra View Post
The answer is d) Modified herpes simplex virus (HSV)

It's sort of experimental-like question (at least to me
But I thought the concept was interesting. I was btw A and D bc I was looking for something that would be either neurotrophic or would cross the BBB. I excluded E bc I thought it would be too dangerous. But bc liposomes will not get into the nucleus D is the answer

Here's the official explanation:

HSV is a very attractive vector for infecting neuronal cells because it can incorporate large genes (up to 40-50 kb), it is neurotrophic, and it can establish latent infection in these cells. It can create an immunologic reaction, but antibody reactions are not severe. HSV does not integrate into the host genome, precluding long-term, stable expression, but this is being overcome with new HSV-AAV combination constructs.
why retrovirus more dangerous than HSV? b/c i was confuse between the two?

thx
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Old 08-08-2012
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Quote:
Originally Posted by Kabutar111 View Post
why retrovirus more dangerous than HSV? b/c i was confuse between the two?

thx
well I guess I would rather have HSV and risk meningitis/encephalitis (if the HSV somehow got its virulence back) than get risk infecting microglial cells by HIV (if HIV got its virulence back). But that's just me
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