Ingredient in human semen may enhance HIV infection

Ingredient in human semen may enhance HIV infection
A man points at an artwork at a conceptual art exhibition about HIV/AIDS in Tehran December 2, 2007. An ingredient in human semen may actually help the HIV virus infect cells, German researchers said on Thursday. (Morteza Nikoubazl/Reuters)CHICAGO (Reuters) - An ingredient in human semen mayactually help the HIV virus infect cells, German researcherssaid on Thursday.
They said naturally occurring prostatic acidic phosphataseor PAP, an enzyme produced by the prostate, can form tinyfibers called amyloid fibrils that can capture bits of thehuman immunodeficiency virus and usher it into cells.
Researchers at the University Clinic of Ulm were lookingfor factors in semen that might block infection with HIV-1, themost common strain of the virus that causes AIDS.
Instead, they found one that enhanced transmission, in someexperiments as much as 50-fold.
"In this study we show that fragments of PAP, a highlyabundant semen marker, form amyloid fibrils that drasticallyenhance the infectiousness of HIV-1," they wrote in the journalCell.
They said they are now looking for compounds that mightblock this process to slow transmission of the disease.
Amyloid fibrils formed from different proteins areassociated with many diseases, including Alzheimer's and priondisease.
"Further studies on the role of amyloids in thetransmission and pathogenesis of enveloped viruses are highlywarranted," they wrote.
HIV has infected some 60 million people, killing more than20 million, the researchers said. More than 90 percent of thoseinfections are acquired through sexual intercourse.
(Reporting by Julie Steenhuysen; editing by Todd Eastham)