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Author Topic: The Holy Grail to HIV cure?  (Read 4745 times)

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Offline marky

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The Holy Grail to HIV cure?
« on: September 27, 2006, 10:00:47 PM »
I have a short press release... and following a longer more "scientific" press release.   

AP
Sangamo Says Compound Shows Potential
Wednesday September 27, 5:29 pm ET 
Sangamo Biosciences Says Compound Shows Potential As HIV Immunization


RICHMOND, Calif. (AP) -- Biotechnology company Sangamo Biosciences Inc. said Wednesday a group of development stage proteins can be used to permanently immunize cells to HIV infection.
Data involving the proteins, called zinc finger DNA-binding protein nucleases, was announced as part of a presentation at a conference in San Francisco. The report results show that administration of Sangamo's compound enabled the generation of HIV-resistant cells.

 
"These are very important data, demonstrating that we are able to generate a population of HIV-resistant immune cells similar to the situation in individuals carrying the natural CCR5-delta32 mutation which confers resistance to HIV infection," said Dr. Dale Ando, Sangamo's vice president of therapeutic development and chief medical officer.



Longer press release:::

Sangamo BioSciences Announces Positive HIV/CCR5-ZFN Data in Presentation at 46th Annual Interscience Conference on Antimicrobial Agents and Chemotherapy
Wednesday September 27, 4:30 pm ET


RICHMOND, Calif., Sept. 27 /PRNewswire-FirstCall/ -- Sangamo BioSciences, Inc. (Nasdaq: SGMO - News) announced today data demonstrating that human immune system cells can be made permanently resistant to HIV infection by treatment with zinc finger DNA-binding protein nucleases (ZFN(TM)). Sangamo's ZFNs are designed to permanently modify the DNA sequence encoding CCR5, a co-receptor that enables HIV to enter and infect cells of the immune system. The presentation, entitled, "Towards Gene Knock Out Therapy for AIDS/HIV: Targeted Disruption of CCR5 Using Engineered Zinc Finger Protein Nucleases" is taking place today at the 46th Annual Interscience Conference on Antimicrobial Agents and Chemotherapy in San Francisco.

 
The presentation is co-authored by Sangamo's collaborators in the laboratory of Dr. Carl June, Director of Translational Research at the Abramson Family Cancer Research Institute at the University of Pennsylvania School of Medicine.

The reported results demonstrate that in T-cell lines and in primary human CD4+ T-cells, administration of Sangamo's CCR5-ZFNs enabled the generation of a population of CCR5-modified, HIV resistant cells. ZFN-modified T-cell lines survived continuous exposure to HIV and expanded to the point that they represented the vast majority of cells in the population at the end of the experiment (70 days). Significant enrichment was also reported for ZFN- modified primary human CD4+ T-cells exposed to HIV. In addition, plasmid DNA plus electroporation and adenoviral vectors were evaluated as modes of delivery of CCR5-specific ZFNs. While both methods support ZFN-mediated CCR5 disruption of T-cells, adenoviral delivery resulted in a ten-fold increase in CCR5-modified cells compared with non-viral methods. Researchers at Sangamo and the University of Pennsylvania are evaluating the long-term consequences and advantages of both delivery methods. Sangamo's clinical goal is to treat T-cells of HIV-infected individuals to generate a reservoir of T-cells that is permanently resistant to HIV infection.

Dale Ando, M.D., Sangamo's vice president of therapeutic development and chief medical officer, commented, "These are very important data, demonstrating that we are able to generate a population of HIV-resistant immune cells similar to the situation in individuals carrying the natural CCR5-delta32 mutation which confers resistance to HIV infection. We believe such a reservoir of healthy and uninfectable T-cells in a patient would be available to fight both opportunistic infections and HIV itself. In addition, we have made significant advances in the production process for this therapeutic approach and determined that delivery of our ZFNs by adenovirus may give us advantages in delivery efficiency and T-cell survival over other delivery methods that we are evaluating."

Dr. Carl June stated, "The positive results being presented at ICAAC continue to strengthen our belief that CCR5-ZFNs are a novel and potentially promising class of anti-HIV compounds. I am greatly encouraged by these findings and look forward to collaborating with Sangamo further to bring this program into the clinic as quickly as possible."

CCR5 is a highly validated therapeutic target for development of drugs to treat HIV. Individuals carrying a naturally occurring mutation of their CCR5 gene, a variant known as CCR5-delta32, have been shown to be resistant to HIV infection. Several major pharmaceutical companies have initiated programs developing small molecule or antibody approaches to block the binding of HIV to CCR5. However, a small molecule or antibody approach to this problem requires the constant presence of a sufficiently high concentration of drug to block therapeutically relevant numbers of the CCR5 protein, which is present in thousands of copies on the surface of each T-cell. The development of several programs to test small molecule antagonists of CCR5 has been halted due to concerns about toxicity of the compounds. In contrast, Sangamo believes that its ZFN technology represents a means of circumventing these limitations. Only brief exposure of immune cells to ZFNs is required for permanent modification of cells' CCR5 protein making them resistant to HIV infection.



Offline Matty the Damned

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Re: The Holy Grail to HIV cure?
« Reply #1 on: September 27, 2006, 10:02:39 PM »
Hey Marky,

Welcome to the forums. Would you like to tell us more about yourself?

Fond regards,

MtD

Offline DingoBoi

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Re: The Holy Grail to HIV cure?
« Reply #2 on: September 27, 2006, 10:10:58 PM »
point being that those whose first post here is a 'cure' is often quackery.

and utterly dismissed.   Do you really think this group of people wouldn't know of something profound in the treatment of hiv?

Voodoo Medicine at best.  Death at worst.

Offline Life

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Re: The Holy Grail to HIV cure?
« Reply #3 on: September 27, 2006, 10:37:22 PM »
or? ;)

Offline Sky

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Re: The Holy Grail to HIV cure?
« Reply #4 on: September 27, 2006, 10:39:36 PM »
I usually dismiss this type of bs as well, but this company is real and there is news on their site about it.  Someone at the hospital I work at mentioned it to me earlier today...so it's something to keep an eye on maybe.

http://phx.corporate-ir.net/phoenix.zhtml?c=120938&p=irol-newsArticle&t=Regular&id=909834&
Poz since 2003.

Offline DingoBoi

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Re: The Holy Grail to HIV cure?
« Reply #5 on: September 27, 2006, 10:46:09 PM »
anyone can form a company and anyone can publish results of supposed lab trials.   Till it gets the AM seal of approval... or at least a notice in their email publications, it's quackery.

Offline Life

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Re: The Holy Grail to HIV cure?
« Reply #6 on: September 27, 2006, 10:47:20 PM »
I dream of a day they truly stumble on "IT," and it could take the form of what we just read and maybe even by a one time poster...  I'll take it however it presents itself....  Hope.... That's all, just HOPE...  For you, me, for all of us..

Offline HIVworker

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Re: The Holy Grail to HIV cure?
« Reply #7 on: September 27, 2006, 11:14:43 PM »
It's a good idea. However, it is gene therapy. Introduction of many genes could help with current HIV infection. While this data is very interesting, I'd like to know how they propose to introduce the gene of interest specifically into CD4 cells. It's a common problem. I am not sure they would be a cure per-se as people who have delta-32 deletions who are infected merely do not progress quickly to AIDS. They don't get cured, or at least I haven't heard of one. Gene therapy will introduce a new wave for therapy for many diseases not limited to HIV. However, it is a matter of getting it into the cells.

I am also curious as to why this is the first post from this poster...

R
NB. Any advice about HIV is given in addition to your own medical advice and not intended to replace it. You should never make clinical decisions based on what anyone says on the internet but rather check with your ID doctor first. Discussions from the internet are just that - Discussions. They may give you food for thought, but they should not direct you to do anything but fuel discussion.

Offline Life

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Re: The Holy Grail to HIV cure?
« Reply #8 on: September 27, 2006, 11:20:35 PM »
well it could just be a nice person expressing him or herself??? ;)
or an "evil duer" >:(

Offline Eldon

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Re: The Holy Grail to HIV cure?
« Reply #9 on: September 27, 2006, 11:56:01 PM »
It is GOOD that there are researchers and scientists out there who are working through many different methods in order to find a cure for HIV/AIDS.


Welcome to the forums Marky. Never give up hope.



Make the BEST of each Day!

Offline otherplaces

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Re: The Holy Grail to HIV cure?
« Reply #10 on: September 28, 2006, 12:31:22 AM »


Whoever Marky is I appreciate the post.  I find all the work in gene therapy to be very interesting and could be the key to get us off of meds, if not permanently at least for a period of time.  I think we can all welcome that.

I guess the "holy grail" would be finding a way to activate the latent infection so it can be cleared.  THAT could lead to a cure.

brian


Offline HIVworker

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Re: The Holy Grail to HIV cure?
« Reply #11 on: September 28, 2006, 12:34:14 AM »
I agree, getting people off therapy has to be a goal.
NB. Any advice about HIV is given in addition to your own medical advice and not intended to replace it. You should never make clinical decisions based on what anyone says on the internet but rather check with your ID doctor first. Discussions from the internet are just that - Discussions. They may give you food for thought, but they should not direct you to do anything but fuel discussion.

Offline Matty the Damned

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Re: The Holy Grail to HIV cure?
« Reply #12 on: September 28, 2006, 12:37:35 AM »
Which is why Matty the Damned wasn't too quick to jump on the tits of this guy and call the stuff he's posted "voodoo medicine" and "quackery". It's full of lab-coat geek terms and some of them sound familiar to me.

Maybe some of our egghead science types can explain in plain english what this stuff means.

-Looks in the direction of HIVworker- ;)

MtD

Offline HIVworker

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Re: The Holy Grail to HIV cure?
« Reply #13 on: September 28, 2006, 12:53:06 AM »
From what I read Matty they have a gene that will process the CCR5 gene prior to protein production in everyone to make it defective for HIV to use it, sort of making your CD4 cells CCR5-D32-like and therefore a LTNP for HIV progression (I shudder to use the c-word). They don't mention how to get the gene in, but that was the gist of it in my 5 mins of reading.

R
NB. Any advice about HIV is given in addition to your own medical advice and not intended to replace it. You should never make clinical decisions based on what anyone says on the internet but rather check with your ID doctor first. Discussions from the internet are just that - Discussions. They may give you food for thought, but they should not direct you to do anything but fuel discussion.

Offline Sky

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Re: The Holy Grail to HIV cure?
« Reply #14 on: September 28, 2006, 12:56:55 AM »
From the sound of it to me it sorta sounds like a theraputic vaccine of sorts.  My question though, like HIVworker said, is how they plan on getting these CD4 altered.
Poz since 2003.

Offline DingoBoi

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Re: The Holy Grail to HIV cure?
« Reply #15 on: September 28, 2006, 01:18:30 AM »
it's okay matty that you don't understand big words like that, nobody expects you to be a hero.

edit:  tit for tat or shall we continue?
« Last Edit: September 28, 2006, 01:26:02 AM by DingoBoi »

Offline Matty the Damned

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Re: The Holy Grail to HIV cure?
« Reply #16 on: September 28, 2006, 01:36:54 AM »
From what I read Matty they have a gene that will process the CCR5 gene prior to protein production in everyone to make it defective for HIV to use it, sort of making your CD4 cells CCR5-D32-like and therefore a LTNP for HIV progression (I shudder to use the c-word). They don't mention how to get the gene in, but that was the gist of it in my 5 mins of reading.

R


Cheers Rich!

MtD

Offline newt

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Re: The Holy Grail to HIV cure?
« Reply #17 on: September 28, 2006, 02:01:18 AM »
Zinc finger (er, ZFN in the press release) has been a speculative target for an HIV therapy for a while, but the technology & biology is difficult.  In this case it's genetic engineering not pharmacology*

Sangamo Biosciences people have presented their work at several major conferences so far, including the essential annual basic & clinical science meeting, the 13th Retrovirus Conf., which was held in Denver at the beginning of this year. As usual, the co's press statement glosses over the difficulties and limitations of this perhaps even excellent lab science.

- matt

*(link from The Molecules of HIV - A Hypertextbook which is handy tour of the bits of HIV, including the ones attacked by current treatments, eg reverse transcriptase, protease, and a relatively simple overview of the different parts of the human immune system and what they do).
« Last Edit: September 28, 2006, 06:36:02 AM by newt »
"The object is to be a well patient, not a good patient"

Offline Matty the Damned

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Re: The Holy Grail to HIV cure?
« Reply #18 on: September 28, 2006, 02:21:31 AM »
Thanks Matt. MtD is enlightened. Thanks especially for the link.

MtD

Offline kcmetroman

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Re: The Holy Grail to HIV cure?
« Reply #19 on: September 28, 2006, 06:51:48 PM »
http://news.yahoo.com/s/nm/20060928/hl_nm/sangamo_dc_1

Okay Baily, here's how you do it.  Position that lil finger that dances all over your screen on the BIG line of letters above.  Push that lil button on the left hand side of that oval thing in your hand.

Walah!

Thanks Marky.  You don't need to put up with any shit.


Offline marky

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Re: The Holy Grail to HIV cure?
« Reply #20 on: September 28, 2006, 09:54:22 PM »
wow..... first off... I'm not a "newbie".  I've actually been a member for over 4 years.  I read from time to time, but post infrequently. In fact this was my first in over a year.  My profile says "newbie"....because I never took the time to update it after the website change. Secondly, if I "was" a newbie being rude is not a good way to welcome people to this site.  I probably chose the wrong subject title.. .but I found the science to be interesting and clearly researched.  I'm a very optimistic person, hopeful that someday we can find a cure for HIV disease.   

Love, Peace and Happiness. 


Offline Matty the Damned

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Re: The Holy Grail to HIV cure?
« Reply #21 on: September 28, 2006, 10:02:34 PM »
wow..... first off... I'm not a "newbie".  I've actually been a member for over 4 years.  I read from time to time, but post infrequently. In fact this was my first in over a year.  My profile says "newbie"....because I never took the time to update it after the website change. Secondly, if I "was" a newbie being rude is not a good way to welcome people to this site.  I probably chose the wrong subject title.. .but I found the science to be interesting and clearly researched.  I'm a very optimistic person, hopeful that someday we can find a cure for HIV disease.   

Love, Peace and Happiness.


Hey Marky, don't sweat it doll. I for one am very grateful to you for the information you posted. I learned something.

Regards,

MtD

Offline HIVworker

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Re: The Holy Grail to HIV cure?
« Reply #22 on: September 28, 2006, 11:08:34 PM »
Marky,

Belated welcome to you then!!! You should post more often - particularly on science!

Forgive this weary person, we have people coming on here to promote thngs for reasons other than education. My apologies if I appeared rash...

Best,

Rich
NB. Any advice about HIV is given in addition to your own medical advice and not intended to replace it. You should never make clinical decisions based on what anyone says on the internet but rather check with your ID doctor first. Discussions from the internet are just that - Discussions. They may give you food for thought, but they should not direct you to do anything but fuel discussion.

Offline DingoBoi

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Re: The Holy Grail to HIV cure?
« Reply #23 on: September 29, 2006, 10:57:09 AM »
http://news.yahoo.com/s/nm/20060928/hl_nm/sangamo_dc_1

Okay Baily, here's how you do it.  Position that lil finger that dances all over your screen on the BIG line of letters above.  Push that lil button on the left hand side of that oval thing in your hand.

Walah!

Thanks Marky.  You don't need to put up with any shit.



Thought you left.

And for you to continue to misspell my name is rude or you are dumb.

it's B A I L E Y


Offline newt

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Re: The Holy Grail to HIV cure?
« Reply #24 on: September 29, 2006, 11:04:34 AM »
This is a civil & so far useful, science thread. If people have personal disagreements, please take them somewhere else.

- matt
"The object is to be a well patient, not a good patient"

Offline Sky

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Re: The Holy Grail to HIV cure?
« Reply #25 on: September 29, 2006, 11:43:01 PM »
No matter what the outcome of this and other finding are, breakthrough's like this truely amaze me.  It's just so incredible to me how people figure this stuff out.
Poz since 2003.

Offline MitchMiller

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Re: The Holy Grail to HIV cure?
« Reply #26 on: September 30, 2006, 12:03:48 AM »
The only thing I wonder about is that the treatment is used to disable the CCR5 receptor so it can't be used by HIV.  But what about other receptors? 

Offline HIVworker

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Re: The Holy Grail to HIV cure?
« Reply #27 on: September 30, 2006, 12:11:45 AM »
Mitch,

That's an excellent question. It would actually be the same as giving a CCR5 inhibitor. HIV uses a main receptor (CD4) and a co-receptor - normally CCR5 but it can evolve to use both CCR5 and CXCR4 and some others. The virus appears to use these other receptors in people on CCR5 inhibitors but the viral load does drop and those drugs appear to work, so if there is a switch it it subtle - so I hear.

There is a concern and this is the tropic switch that occurs during AIDS - co-receptor usage from CCR5 to CCR5 and CXCR4. I have not seen much data on this, so I can't comment other than I heard that it isn't a problem. A cure using this treatment here though? Hmmm, for the reason you suggest mean that it would be doubtful. If it hit CD4, then it would be more interesting. However, although we can live with defective CCR5 receptors (as CCR5 inhibitor studies appear to show) we can't live without CD4. So this would represent a therapy that would get people off medication - if they can deliver it to the right cells - and that is very welcome.

As we all know, it takes much to claim a cure because HIV is a tough nut to crack.

Rich
« Last Edit: September 30, 2006, 12:14:38 AM by HIVworker »
NB. Any advice about HIV is given in addition to your own medical advice and not intended to replace it. You should never make clinical decisions based on what anyone says on the internet but rather check with your ID doctor first. Discussions from the internet are just that - Discussions. They may give you food for thought, but they should not direct you to do anything but fuel discussion.

Offline kcmetroman

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Re: The Holy Grail to HIV cure?
« Reply #28 on: September 30, 2006, 01:24:01 AM »
Indeed, I am led to believe that even if a cure were developed and the viral reproduction were stopped, it would take 60 years to completely flush the virus from our bodies.

Offline Sky

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Re: The Holy Grail to HIV cure?
« Reply #29 on: September 30, 2006, 01:28:11 AM »
I think 60 years is only if the latent reserve isn't activated.  From my understanding they've pinpointed two drugs that can make the latent reserve active.
Poz since 2003.

Offline whizzer

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Re: The Holy Grail to HIV cure?
« Reply #30 on: September 30, 2006, 09:14:17 AM »

The latent reservoir, that is, the latent reservoir manifested by resting CD4 cells, is always activated.  CD4s encounter foreign antigens, form blasts, then activate other cells to fight the invader.  A few encounter the foreign antigen, then go into a resting state before carrying out this process.  In the future, if they encounter the antigen again, they "wake up", form blasts and start the process all over again.  This is how we develop cell memory of foreign antigens, and thus, immunity.  Trouble is, some of theses CD4s can be infected by virus during this process; the virus undergoes reverse transcription and integration before the cell goes into a resting state.  Viral replication stops while in the resting state, but when the CD4 becomes activated again, viral production resumes.

Robert Siliciano estimates, based on decay rates and the half life of resting CD4 cells, that a person on HAART, with viremia controlled below 50 copies (blips not included), would take 73 years to clear the virus.

Here's an old (1998) but useful explanation of the resting CD4 reservoirs:

http://www.natap.org/1998/forums/forums_siliciano.htm

And here's a 2006 update on the subject (you have to register with clinical care options to read the module, but it's free to join):

http://www.clinicaloptions.com/hiv/annual%20updates/2006%20annual%20update/modules/siliciano.aspx

Offline Razorbill

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Re: The Holy Grail to HIV cure?
« Reply #31 on: September 30, 2006, 09:23:51 AM »
Let's see I'm 47.  If it took 73 years to clear the virus, I'd be 120.  The oldest authenticated person, a French woman, died at 122 years 164 days.  There's hope!

Offline HIVworker

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Re: The Holy Grail to HIV cure?
« Reply #32 on: September 30, 2006, 09:50:56 AM »
Honestly, if latent infection is not dealt with it can't be a cure. Besides, Robert Siliciano found another problem with HIV; that of persistant replication on Meds. Actually, he didn't find it, but he has characterized it. If you want to know the barriers to the cure I suggest you look up his work. He came to give a seminar called, "Barriers to the cure" that was a little depressing. However, if you want to cure it you need all the cards on the table...

R
NB. Any advice about HIV is given in addition to your own medical advice and not intended to replace it. You should never make clinical decisions based on what anyone says on the internet but rather check with your ID doctor first. Discussions from the internet are just that - Discussions. They may give you food for thought, but they should not direct you to do anything but fuel discussion.

Offline whizzer

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Re: The Holy Grail to HIV cure?
« Reply #33 on: September 30, 2006, 10:35:58 AM »
Yes, well, 73 years is a long time, too long for all of us.  Fortunately, there aren't that many resting CD4s - about one out of every million CD4 cells is resting at any given time.  Unfortunately, even on successful HAART, viral replication is ongoing, which means the latent reservoir of resting CD4s is constantly being replenished, albeit to a greatly reduced degree.  This is even more of a problem if drug resistant virus is present in great amount.

But there IS hope.  It is postulated that by using fusion inhibitors (there's only one now, but more are on the way) and entry inhibitors, such as CCR5 inhibitors, to prevent the infection of CD4s before they can enter the resting state, that this time period will be reduced significantly.  That, or the amount of virus in the body will be substantially reduced so that some sort of therapeutic vaccine can finish the job.  Clinical studies are ongoing to prove (or disprove) this concept of reduction of infection of the resting CD4 reservoir.  These studies will most certainly NOT result in a cure for HIV, but are, perhaps, a step in the right direction.  Alas, it all still hinges on controlling the viremia, which leaves out those with drug resistance.

I am hopefull.  That's why I joined a study examining this concept.  That's why I inject the hated Fuzeon twice a day, even though I have no resistance and could certainly take Atripla once a day and be done with it (a once a day regimen, I have to admit, appeals greatly to me at this point in time).  I'll let you know in a couple of years if it has any effect on my resting CD4s.

Wish I could hear Siliciano's latest lecture.  I was in San Francisco when he gave his "Barriers to the Cure" lecture at Berkely, but I didn't know about it at the time.  Damn.

-Whiz
(who's degree of hopefullness varies from day to day)

Offline HIVworker

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Re: The Holy Grail to HIV cure?
« Reply #34 on: September 30, 2006, 02:22:55 PM »
Whizzer,

Robert Siliciano's lecture was sobering at the very least. I got to talk to him for 30 minutes one on one and mainly talked to him about Blipping - you might remember he wrote a paper on it. I was interested to hear his perspective on the topic as the magnitude of BLIPS vary somewhat and we had a discussion here about it.

About the entry inhibitors and latency. Just something to think about regarding your idea that entry inhibitors would put pay to establishing or re-filling a latent pool. Currently there is an entry inhibitor - Fuzeon - that doesn't appear to diminish this pool. I also have to add that both NRTIs and NNRTIs would also prevent the establishment of a latent pool as would an integrase inhibitor. All three classes would protect a HIV naive cell from getting integrated viral DNA prior to it going back to the resting state. As far as I am aware none of the three classes do anything to prevent the filling or re-filling of this pool. Latency is also established early, although it is probably dynamic. Protease inhibitors would be the only ones that did nothing to prevent the latent pool being established or re-filled. I guess the answer to the latent problem might lie in the specific targetting of antiretrovirals to cells that are more prone to harboring latent infection - and currently neither Robert Siliciano or anyone else really knows the identity of these cells. If this was known, more could be done to target existing classes of drugs to them. If one could do that, then you would have to study the latent pool solely while on HAART to see if it was no longer being topped up. Then you would have to tackle the persistent pool that, like it's latent brother, remains poorly resolved...

Rich
« Last Edit: September 30, 2006, 02:25:19 PM by HIVworker »
NB. Any advice about HIV is given in addition to your own medical advice and not intended to replace it. You should never make clinical decisions based on what anyone says on the internet but rather check with your ID doctor first. Discussions from the internet are just that - Discussions. They may give you food for thought, but they should not direct you to do anything but fuel discussion.

Offline HIVworker

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Re: The Holy Grail to HIV cure?
« Reply #35 on: September 30, 2006, 02:24:31 PM »
Doublepost sorry...
NB. Any advice about HIV is given in addition to your own medical advice and not intended to replace it. You should never make clinical decisions based on what anyone says on the internet but rather check with your ID doctor first. Discussions from the internet are just that - Discussions. They may give you food for thought, but they should not direct you to do anything but fuel discussion.

Offline newt

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Re: The Holy Grail to HIV cure?
« Reply #36 on: September 30, 2006, 02:52:22 PM »
Yes well. The "red herring" here is (exclusive concentration on) CD4, it's not the only target of infection.  But it is the driver for current therapeutic interventions, and much of what else HIV does is not brilliantly understood (like what, exactly, does it do with fat cells, hmmm?). Obiously CD4 is not really a red herring, perhaps very light pink, but CD4 not the be all and end all of HIV & the immune system. HIV is like family, it's easy to forget about some of them but they always pop up sooner or later. - matt
"The object is to be a well patient, not a good patient"

Offline J220

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Re: The Holy Grail to HIV cure?
« Reply #37 on: September 30, 2006, 03:52:23 PM »
Correct me f I'm wrong, guys, but I think there is no incontrovertible evidence that hiv-infected CD4 cells live that long, is there? I think it's more along the lines of "it is believed. And along the same lines, I think there is no conclusive evidence either that latent cells are the reason haart therapy fails to clear the virus. For all we know it's just a matter of ongoing replication that is not reached by haart, such as in the gut, as recently reported by a research team.

My point is there is more that is not known than known when it comes to the dynamics of the persistent nature of the infection and why it has eluded clearing so far, and even Dr. Siciliano does not have all the answers about this and his is not the final word.

Personally, I have great confidence that it won’t be long before the key datum is discovered that leads to a way to clear the infection. In fact it may have happened already with the discovery of how hiv uses the PD-1 protein to suppress CD8 cells so they don’t kill off infected cells. Reserchers were able to restart CD8 cells by blocking PD-1, and they resumed their targeting of virus-infected cells. That's a very good sign. J.
« Last Edit: September 30, 2006, 04:55:52 PM by J220 »
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Offline HIVworker

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Re: The Holy Grail to HIV cure?
« Reply #38 on: September 30, 2006, 10:48:45 PM »
The problem is both persistence and latency not either or. On HAART there is ongoing replication of a small pool of virus that is quite restricted in its genotype, meaning the pool is small. Drugs can't get to that. There is actually no evidence that the virus you can pick up during HAART is active. Latent infection is believed to be one reason that HIV can't be cleared but it isn't the only one - this persistant pool is a contributing factor. However, as it is known that HIV can 'hide' in latent cells and this pool (or cells) have a long half-life, latency remains a significant barrier to eradication.

R
« Last Edit: September 30, 2006, 10:54:42 PM by HIVworker »
NB. Any advice about HIV is given in addition to your own medical advice and not intended to replace it. You should never make clinical decisions based on what anyone says on the internet but rather check with your ID doctor first. Discussions from the internet are just that - Discussions. They may give you food for thought, but they should not direct you to do anything but fuel discussion.

 


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