Duke Health

Scientists from Duke Medical Center have apparently identified a set of naturally occurring antibodies which they claim may be able to thwart the key ways in which the AIDS virus enters human blood cells. This breakthrough has led to the expansion of ideologies behind how the immune system fights HIV. These findings also seem to offer scientists with potential new ways of designing HIV vaccines.

Researchers have been confused and aggravated with the responses generated by antibodies towards HIV. Typically in most infections, antibodies that ward off invading pathogens, appear to reveal themselves quickly and get right to work. However in the case of HIV, the antibodies somehow do not materialize until weeks or even months after the initial infection.

Senior Scientist Anthony Moody, MD, member of the Center for HIV/AIDS Vaccine Immunology (CHAVI) comments, “The beauty of this newly identified set of antibodies, called polyreactive anti-phospholipid antibodies is that they are so potent against the type of virus that establishes infection during mucosal transmission. Our research suggests we may be able to harness them and enhance their anti-viral activity with a vaccine to fight HIV directly.”

Moody explains that the antibodies PGN632, P1, IS4 and CL1 do not seem to have pathogenic features, although the other members of the same class do. Research conducted earlier indicates that anti-phospholipids antibodies have anti-viral elements, but through this research, Moody and his team are trying to establish the working of these antibodies.

The team via a series of lab-tests on blood samples procured from HIV-infected patients as well as healthy participants discovered that when these antibodies combine with the white blood cells (monocytes), it leads to the secretion of a substance known as chemokines. These chemokines block the HIV from docking with its preferred position in the blood cell, the CCR5 receptor.

In other words, these chemokines do not go after particular viral particles directly, but rather move indirectly by creating a chemical roadblock at one of the portals most commonly used by the virus to enter the cells. Nevertheless, this act does not take place always. The results garnered from the research show antiviral activity in only 85 percent of the blood and that also only in the presence of monocytes.

Scientists believe that the findings from this research have substantial importance since most of the HIV strains use the CCR5 receptor for entrance into the cell. As this is the earliest occurrence in the entire process of infection, potential intervention at that juncture could prove worthy enough.

Senior scientist Barton Haynes, MD and Director of CHAVI and the Duke Human Vaccine Institute said that, “There are two parts of the immune system, the innate and adaptive components, and this study shows a vaccine that could elicit these polyreactive antibodies could recruit both components to fight HIV.”

Haynes further adds that they have long assumed that a successful vaccine would probably need to attack HIV on multiple fronts. These findings seem to have given them another potential way to use the immune system to fight HIV.

The findings were published online in the Journal of Experimental Medicine.