POZ Community Forums
Meds, Mind, Body & Benefits => Research News & Studies => Topic started by: datdude on February 03, 2009, 02:35:36 pm
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Gene therapy that could immunize people against the most common type of HIV is ready to be tested on humans.
Recruiting for the trial began Tuesday, and the first people to receive the experimental treatment will be HIV patients with drug-resistance problems.
"We do have good treatments for HIV. That has been one of the most successful stories of the last 20 years in medicine," said Pablo Tebas, an infectious disease expert at the University of Pennsylvania.
"However, over time, if the medications are not taken properly, individuals develop resistance to the HIV treatments, so they tend to have more limited therapeutic options."
Since the discovery that a small portion of people who are exposed to HIV do not get infected, scientists have been working to discover the secret to those people's resistance and how to make others resistant as well.
It turns out that most people have a gene called CCR5, which makes them vulnerable to HIV infections. The naturally resistant people have mutant CCR5 genes that inhibit HIV.
Previously, scientists found that by cutting the CCR5 gene out of white blood cells involved in the immune response known as T-cells, they could protect a tube full of human cells from the virus. The gene editing technique relies on proteins called zinc finger nucleases that can delete any gene from a living cell.
In theory, zinc finger nucleases could give that immunity to anyone.
The procedure is simple: Take some healthy T-cells out of an HIV patient, clip out their CCR5 genes, grow more of these clipped T-cells in a dish, and then put them back in the patient.
"In this first study we will re-infuse approximately 10 billion of these cells back into the participants, and we will see if it is safe and if those cells inhibit HIV replication in vivo," said Tebas. "We know they do in the test tube."
http://blog.wired.com/wiredscience/2009/02/hivtreatment.html
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Huge news!!
Let's hope zinc gives HIV the finger!
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I swear if this works I'm going to retire and start a band called ZincFinger.
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freewillie99,
Can I be one of "The Boys in the Band" ? (lol).
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freewillie99,
Can I be one of "The Boys in the Band" ? (lol).
Groupies are always welcome!
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freewillie99,
WOOHOO!
"A groupie is a person who seeks sexual and/or emotional intimacy with a celebrity."
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but if they succeed in cutting off the CCR5 or remove it,wouldnt the virus just still infect the CD4 using the CXCR4 ?
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but if they succeed in cutting off the CCR5 or remove it,wouldnt the virus just still infect the CD4 using the CXCR4 ?
Theoretically, yes. That's not to say that a different regimen can't be developed targeting x4-tropic virus. The link below is an excellent overview of CCR5 and CCRX4 and to what extent they are found among 865 samples of HIV-infected individuals. Basically, "Overall, 80% of the viruses tested exclusively utilized the R5 receptor; only 4 samples exclusively used X4, while the remainder were dual tropic (R5/X4). The prevalence of R5 virus was not influenced by age, gender, virus clade, ethnicity or antiretroviral exposure." Apparently after initial exposure and for a long time afterward, most people have CCR5-tropic virus.
http://www.thebody.com/content/art15559.html
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but if they succeed in cutting off the CCR5 or remove it,wouldnt the virus just still infect the CD4 using the CXCR4 ?
As pointed out above, only if the strain was dual tropic. There's no information I've ever read about that says once an R5 oriented virus is blocked that it would therefore mutate to become X4 tropic.
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Found this study:
http://arstechnica.com/science/news/2005/12/2145.ars
(Once the virus takes hold and begins replicating, it typically evolves to use the CXCR4 receptor.)
It's a toss-up.
veritas
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"Apparently after initial exposure and for a long time afterward, most people have CCR5-tropic virus. "
does that mean drug experienced patients will have the 2 types of receptors after several years of being on medication ? which means they wouldnt benifit from the current study if it's proven sccessfull ?
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sensual1973,
this therapy will not work on X4. The potential to have X4 increases the longer you have the virus.
veritas
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almost 5years on drugs here (poz since 2001) is that long enough to make me almost excluded from benifiting from the study ?
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You have to take a trophism test to determine which receptor is present. In order to take that test you must have a viral load of at least 1000. So the short answer is: "It's a toss up".
veritas
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I see this as a good sign for starting HIV Gene Therapy.
There is two HIV Gene Therapy now that is this one and VRX496.
If both of this become successful, we will now move beyond HAART and more HIV Gene Therapy will come.
This is good starting. Be Strong.
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does that mean drug experienced patients will have the 2 types of receptors after several years of being on medication ? which means they wouldnt benifit from the current study if it's proven sccessfull ?
What's weird is that the patient in Germany, who was cured of HIV and lymphoma through the bone marrow transplant that used a donor with the delta-32 mutation, had dual-tropic virus to begin with. You would think that if his CCR5-tropic virus was blocked after the transplant that his CXCR4 virus would have taken hold but it hasn't so far.
Not only has the HIV not come back but testing shows fewer and fewer antibodies to HIV, making the doctors speculate that there will come a point when he will actually test HIV-Negative.
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Yap the personalised version will have success since the body is able to heal itself from many infections, to connect i think i was reading about another 1 personalised trials thats showing efficacy, i think this is the right direction as opposed with a universal drug with a disease that mutates accross a population, this will show significance ;D i am very hope about this, in general the personalised approach rather than the gene therapy Zinc Fingers but they could also work, according to the results its good, ;) im betting my chances on the personalised version, they all sound as if they are going to work but when its testing time its when they scrap their theories, 8) i can bet on gene therapy first becoz if they also work out from what i hav been reading they could start from the root where the cell are manufactured and ensure that the blood cells manufactured are already immune to the virus ::) Zinc Fingers lets Hope It works
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Yap the personalised version will have success since the body is able to heal itself from many infections, to connect i think i was reading about another 1 personalised trials thats showing efficacy,
That is an interesting thing. Can you share with us the news (or the gossip ;D) about "another 1 personalized trial thats showing efficacy?".
Love to hear the story. Tx
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New gene therapy halts 2 boys' rare brain disease
WASHINGTON – French scientists mixed gene therapy and bone marrow transplants in two boys to seemingly halt a brain disease that can kill by adolescence.
The surprise ingredient:
They disabled the HIV virus so it couldn't cause AIDS, and then used it to carry in the healthy new gene.
http://news.yahoo.com/s/ap/us_med_gene_therapy
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Great Success, i personally think gene therapy holds key to more disease, :D i think there are more research going on and results may be coming from time to time, but some questions of this post, the boys were given a killed form of the virus (hiv) as the delivery vehicle of normal cells, thats wat i put trust on like putting taking hold of the root bone marrow so that cells made from there are modified and can resist attacks from the virus, however i dont see a lot of reports about this on HIV and please clarify on the boys infection with a killed virus, any risk them getting infected later on???.
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That is an interesting thing. Can you share with us the news (or the gossip ;D) about "another 1 personalized trial thats showing efficacy?".
Love to hear the story. Tx
Argos Therapeutics to Discuss Personalized Dendritic Cell Immunotherapy any idea on this one
and i am getting Confused Zinc Fingers, dendric cells most recent post and this gene therapy
http://www.asgt.org/am09/asgct_news/index.php?pagecontent=page2&sessioncontent=11
it sounded the most promsing if you read carefully the number of weeks, also look at the approach, any progress anyone who knows.
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If the CCR5 receptor cut off, so it would be somehow strange for virus to mutates within its short lifetime and then become CXCR4 tropic.