From: weemba@sagi.wistar.upenn.edu (Matthew P Wiener)
Newsgroups: sci.skeptic
Subject: Re: AIDS and the CIA (was Question)
Date: 16 Nov 92 14:30:57 GMT
Reply-To: weemba@sagi.wistar.upenn.edu (Matthew P Wiener)
Organization: The Wistar Institute of Anatomy and Biology
In-reply-to: SCW112@psuvm.psu.edu

In article <92320.194233SCW112@psuvm.psu.edu>, SCW112@psuvm writes:
>>>That's why HIV remains dormant -- It's sitting inside your DNA until
>>>something (some environmental factor) turns it on and you get AIDS.

>>This is unknown.  As a retrovirus, HIV forms DNA instructions for itself
>>in host cells, and they join in with the rest of the chromosomes.  The
>>cell at some point uses the viral DNA as if it were its own, repeatedly.
>>It will do this without any special environmental factor.  Retroviral
>>infection is, in fact, a common technique in the recombinant DNA world.

>True, the cell will replicate&all progeny cells will contain the viral genes,
>but just because you have lots of these cells doesn't mean you have AIDS,
>Something has to make the cell go from the lysogenic to the lytic phase to
>create more copies of virus. What? An environmental factor, maybe. We don't
>actually know. It could just be a matter of time.

You don't quite understand.  Retroviruses don't need a lytic phase to
spread.  A retrovirally infected cell's life cycle now includes budding
off new retroviruses now and then, slowly.  The cell can do this without
bursting.  Which is part of the reason retroviral infection is a common
technique, as mentioned above.

In particular, I do not believe the HIV-kills-T-cells-causing-AIDS theory. 
I favor the network theories, which state that the immune response to HIV
is the wrong response and actually causes the disease.  And this response
happens regardless of environment or ongoing cell lysis.

>>>As to the reason why we don't have an HIV vaccine, it's easy to make
>>>a vaccine.  All a vaccine is is like a part of a virus that provokes
>>>the immune system to create antibodies against that virus. We could
>>>make an AIDS vaccine right now, I'm sure.

>>No, we can't.  A vaccine has to induce the correct immune response.
>>We do have trial AIDS vaccines though.

>What's a vaccine? It's something that makes your body produce
>antibodies.

Good grief.  Everything induces antibodies.  At this rate, the word
"vaccine" won't mean anything.

>	     Hell, _I_ could make an AIDS vaccine. Just take a bunch
>of HIV viruses and kill 'em.  That, if injected into a human, would
>provoke an immune response.

Yes.  And you have no a priori knowledge of whether this will produce
antibodies against HIV.  Your method of killing could break the relevant
proteins that end up expressed on cell surfaces.

>As to whether that would make you immune to HIV, I'm not sure.

That is the point.  If you don't know, don't call it a vaccine.

>>It is unknown why our body's response to HIV is a failure.  This unknown
>>is a major stumbling block in theorizing, let alone designing, an AIDS
>>vaccine.  The models that make the most sense to me say HIV uses judo.
>>The immune system is thrown against the virus, and it misses, badly.
>>If so, tinkering with this will not be easy.

>That's why I don't think a vaccine is the way to go. Finding a cure would be
>better, I think.

But finding a cure is probably impossible.  Read what I wrote.  We don't
know what's going on, and we only know how portions of the immune system
work anyway, so fixing this after the fact is beyond current expectations.

At the moment, prevention is the only way to go.  That's it, and people
don't want to hear it.

>>That is only part of the problem, although a minor one according to
>>most researchers.  The other difficulty is HIV's high mutation rate.
>>It's hard to hit a moving target.

>True, but it's not mutation _that_ quickly, so it's a problem, but
>not a huge, huge problem as long as a new mutation doesn't screw up
>the part of the virus that you base your vaccine on.

Welcome to the world of AIDS research.  That *is* the problem.  It mutates
_that_ quickly.  There are numerous candidate vaccines out there.  They work
beautifully in vitro.  They fail in applications, because HIV mutates too
fast.
-- 
-Matthew P Wiener (weemba@sagi.wistar.upenn.edu)
Newsgroups: sci.skeptic