December 14, 2007

Why HIV Vaccines Don’t Work

A new study from researchers at the University of Missouri and Imperial College London have found evidence of why some cancer and HIV vaccines don’t work, according to a University of Missouri press release. The research is published in the December 14 edition of The Journal of Biological Chemistry (eurekaalert.org, 12/13).

Using more than a decade’s worth of research, investigators at the two schools discovered that HIV, aggressive cancer cells, H. pylori (a bacterial strain that causes stomach ulcers) and some parasitic worms all carry a sequence that may block the vaccine’s ability to fight them.

The article notes that in the initial stages of life, the human body identifies which cells and proteins belong to the body so that it can detect and flag any foreign cells and proteins that may be introduced. However, some foreign bodies, like sperm, label themselves with a sequence that tells the body not to mark them as foreign. This is key to the body’s ability to reproduce.

However, the journal reports, the researchers have discovered that HIV infected cells, aggressive tumor cells and other foreign bodies also carry the Lewis sequence, which may shut down the immune response that allows vaccines to work.

 “If aggressive cancers and pathogens are using the same system of universally recognizable markers to trick the immune system into ‘thinking’ they’re harmless, we need to determine exactly how this interaction works,” said Anne Dell, an investigator at Imperial College London. “This is where we’re planning to take this research next. Understanding how these markers work at a basic biological and chemical level could lead to new ways to treat or prevent cancers and these other diseases in the future.”

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Previous Comments:

MICHAEL B, SAN FRANCISCO, 2007-12-21 04:29:25
Why not coat the vaccine with a Lewis sequence like sperm have and/or strip the HIV infected cells and aggressive tumor cells that also carry the sequence?

michelle lopez, Brooklyn, 2007-12-20 14:58:10
This is very interesting. I always wonder how successful we would be with a vaccine for HIV, when in order for a Vaccine to be successful it must be atunated and due to the nature of the HIV virus this is impossible. HIV replicates so how could we prevent its replication and mutation should be one of our goals. I am not a science geek but common knowledge of the HIV Virus and its life should be a motivation of how to approach finding a cure from a vaccine.

Dan Lilley, , 2007-12-19 21:21:27
So...why not find a way to tag HIV with a binding agent that alters the markers which make it inaccessible to vaccines? In other words, find a mechanism that recognizes some unique chemical property of HIV, then attach a "beacon" chemical that identifies the virus as a susceptible target. To some degree, it seems that is already happening in HIV-infected people, otherwise the immune system would ignore it and not be victimized by the virus. Just a thought.

pl, Los Angeles, 2007-12-19 20:46:34
Maybe cancer and HIV researchers should work together to uncover a way to interrupt the sequence... they aim for the same goal

conrad callihoo, vancouver, 2007-12-19 01:54:02
i am not taken any hiv med and iwill not