Posted on 12/24/2009 11:38:17 PM PST by neverdem
Scientists seeking to understand how to make an AIDS vaccine have found the cause of a major roadblock. It turns out that the immune system can indeed produce cells with the potential to manufacture powerful HIV-blocking antibodies – but at the same time, the immune system works equally hard to make sure these cells are eliminated before they have a chance to mature.
"These studies show that a potentially protective neutralizing antibody against a viral disease is under the control of immunological tolerance," said Barton Haynes, M.D., director of the Center for HIV/AIDS Vaccine Immunology (CHAVI) at Duke University Medical Center and senior author of the study appearing in the online early edition of the Proceedings of the National Academy of Sciences. "This represents a new insight into the way HIV effectively evades detection by the B cell arm of the immune system and may offer new directions for vaccine design."
Over the years, scientists have assumed that B cells – one of the first lines of defense against infection – are simply not able to "see" the HIV virus. HIV has the ability to hide its most vulnerable parts from immune system surveillance, and researchers generally assumed that helped explain why B cells often took weeks and even months to arise following infection.
But several years ago, Duke researchers hypothesized that the antibodies required to broadly neutralize HIV may not be produced in the first place because the immune system "sees" them as a potential threat – due to their similarity to antibodies that promote autoimmune disease – and destroys them.
To see if this is indeed what happens, Laurent Verkoczy, Ph.D., assistant professor of medicine at Duke and the lead author of the study, and Haynes genetically engineered a mouse that could only produce B cells containing a rare but potent broadly neutralizing human antibody that is able to block HIV infection.
Researchers found that the mouse's immune system produced plenty of early stage B cells bearing this human neutralizing antibody on their surface but eliminated most of them before they had a chance to fully evolve into more mature B cells capable of secreting the antibody.
"This work may mean that we need to think and act very differently in envisioning how a successful vaccine may work," said Verkoczy. "The good news is that while about 85 percent of the "right" kind of B cells are eliminated, about 15 percent survive and wind up in circulating blood, but are turned off. One goal in vaccine design may be to figure out how to wake them up so they can go to work."
"We have now unveiled a major reason why members of this class of neutralizing antibodies are not routinely made: Our own immune systems block their production because they are perceived as potentially harmful, when in reality, they are not," said Haynes. "This is a very unusual way the virus has developed to evade the immune system."
Haynes says researchers plan on using the new mouse model to test ways to teach the immune system to enable the production of powerful neutralizing antibodies capable of blocking HIV.
Source : Duke University Medical Center
I never read about "knock-in strains" before. Correct me if I'm wrong, but "knock-in strains" are due to the creation of chimeras, i.e. human/animal hybrids.
I am not sure thatchimeras are a factor. All life on earth shares DNA, so every animal is a chimera.
Why not develop genetically engineered antibodies like they develop genetically engineered weaponized viruses
One problem is that your body is apparently really honed at figuring out what belongs there and what doesn’t. The fact that we get bacterial and viral infections at all is sort of amazing. The ones that slip by the body’s defenses are really really good at what they do. Experiments have gone slowly in this genetically engineered antibodies because of the potential of severe allergic reactions to foreign or otherwise unknown agents being introduced to the body.
It’s almost as though God doesn’t want people to commit sodomy.
The big block is money. If they cure something; they aren’t making money.
Your bloodthirsty demon-god is rather careless about collateral damage. A good thing he's just a sick fantasy.
The world would be better off if people like you would become decent human beings.
Merry Christmas.
nice Arabic on your home page...
The Arabic on my home page is a repudiation of Islam. It could get me executed in Saudi Arabia.
There is no shaming you people.
The effect of pretending it's true == harmful to oneself and others.
Because you're not talking about the existence of God, but of a particular kind of horror that you call God.
Like the fellow who thinks God sent AIDS to punish sodomites without regard to innocent people getting it too.
That God cannot exist.
It’s almost as though God doesn’t want people to commit sodomy.
freekitty wrote:
The big block is money. If they cure something; they aren’t making money.
I'm almost sure there's a quip in there somewhere about "You cannot serve God *and* mammon" but I'm not sure what it is.
Cheers!
Why don't you go over to Tehran or Islamabad and personally spread the good news that there is no Allah?
Cheers!
...and Merry Christmas.
I think you got it.
But the desperate fascination with God by the "atheist" is a *very* good proof of his existence, and with atheism itself as a mental disorder.
Hint: I have yet to see a single atheist buying billboards on Brit buses warning people against the dangers of Odin or Poseidon.
Nor do I see atheist missionaries going to Islamic Countries, risking death, imprisonment, and torture, to spread the good news that there is no Allah.
This despite their impassioned circle jerks on college and university grounds, saying how horrible the US theocracy led by George Bush, and threatening to spring up again under Sarah Palin, is.
Nor yet do I see worldwide charities and hospitals based UPON the enlightened Promethean understanding that the laws of Thermodynamics proclaim all life to be unavailing and ultimately meaningless and futile.
Nice try, though.
Merry Christmas.
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