Shooting ourselves in the foot

http://www.eurekalert.org/pub_releases/2007-12/uom-nss121307.php

Public release date: 13-Dec-2007
Contact: Christian Basi
BasiC@missouri.edu
573-882-4430
University of Missouri-Columbia

New study suggests why vaccines directed against cancer, HIV don't work
Mizzou, Imperial College London researchers found that chemical markers prevalent on cancer and HIV-infected cells can fool the body and make immune cells and antibodies leave them untouched
COLUMBIA, Mo. ¬— Researchers from the University of Missouri and Imperial College London have found evidence suggesting why vaccines directed against the virus that causes AIDS and many cancers do not work. This research is being published in the Dec. 14 edition of The Journal of Biological Chemistry.

In research spanning more than a decade, Gary Clark, associate professor of Obstetrics, Gynecology and Women’s Health in the MU School of Medicine, and Anne Dell, an investigator at Imperial College London, found that HIV, aggressive cancer cells, H. pylori, and parasitic worms known as schistosomes carry the same carbohydrate sequences as many proteins produced in human sperm.

“It’s our major Achilles heel,” Clark said. “Reproduction is required for the survival of our species. Therefore we are ‘hard-wired’ to protect our sperm and eggs as well as our unborn babies from any type of immune response. Unfortunately, our results suggest that many pathogens and tumor cells also have integrated themselves into this protective system, thus enabling them to resist the human immune response.”