HIV-1 movement across genital tract cells surprisingly enhanced by usurping antibody response

Infectious disease researchers have identified a novel mechanism wherein HIV-1 may facilitate its own transmission by usurping the antibody response directed against itself. These results have important implications for HIV vaccine development and for understanding the earliest events in HIV transmission.

In a study appearing in the November issue of PLoS Pathogens, Dr. Donald Forthal of UC Irvine and colleagues studied the mechanisms employed by the virus to cross genital tract tissue and establish infection. Since cervicovaginal fluid is acidic and HIV-1 in cervicovaginal fluid is likely coated with antibodies, they explored the effect of low pH and HIV-1-specific antibodies on transcytosis, the movement of HIV-1 across tight-junctioned epithelial cells.

The researchers found that the combination of HIV-1-specific antibodies and low pH enhanced transcytosis as much as 20-fold.

Virus that underwent transcytosis under these conditions was infectious, and infectivity was highly influenced by whether or not the antibody neutralized the virus. They observed enhanced transcytosis using antibody from cervicovaginal and seminal fluids and using transmitted/founder strains of HIV-1. Enhanced transcytosis was due to the Fc neonatal receptor (FcRn), which binds immune complexes at acidic pH and releases them at neutral pH. Finally, staining of human tissue revealed abundant FcRn expression on columnar of penile urethra and endocervix.

More information: www.plospathogens.org/article/… journal.ppat.1003776

add to favorites email to friend print save as pdf

Related Stories

New research shows promise for possible HIV cure

Dec 03, 2013

Researchers have used radioimmunotherapy (RIT) to destroy remaining human immunodeficiency virus (HIV)-infected cells in the blood samples of patients treated with antiretroviral therapy, offering the promise ...

Study explores barriers to HIV vaccine response

Sep 20, 2013

Researchers at The Scripps Research Institute (TSRI) discovered that an antibody that binds and neutralizes HIV likely also targets the body's own "self" proteins. This finding could complicate the development of HIV vaccines ...

HIV vaccines elicit immune response in infants

Oct 08, 2013

A new analysis of two HIV vaccine trials that involved pediatric patients shows that the investigational vaccines stimulated a critical immune response in infants born to HIV-infected mothers, researchers at Duke Medicine ...

Recommended for you

Condoms 'too small' for Uganda men

Sep 19, 2014

Ugandan MPs have been inundated with complaints that many condoms on sale in the east African nation are too small, warning the problem is a blow to the fight against AIDS.

Withdrawal from the evolutionary race

Sep 18, 2014

In some HIV sufferers, the immune system does not fight off the immune deficiency virus. Instead, the body tolerates the pathogen. A research team headed by ETH Zurich has now determined how strongly patients ...

The genetics of coping with HIV

Sep 16, 2014

We respond to infections in two fundamental ways. One, which has been the subject of intensive research over the years, is "resistance," where the body attacks the invading pathogen and reduces its numbers. Another, which ...

User comments