Using Bacteria to Protect Against HIV

Using Bacteria to Protect Against HIV

In Wired News, an article "Anti-HIV Bacterium Isolated?" by Rowan Hooper was posted 02:00 AM Apr. 20, 2005 PT, suggesting that hope for an answer to HIV infection may be nearer. Researcher Lin Tao from the University of Illinois at Chicago's dentistry college and colleagues

A close look at HIV. Image Source: Wikimedia

from Rush University have discovered a strain of lactobacillus, that "binds to the sugar envelope on the surface of HIV," thus targeting HIV "because it uses the sugar as a food source." Why is this important? Two strains of this harmless bacterium, found in the oral and vaginal cavities of healthy human volunteers, trap the HIV virus by eating mannose (a sugar) and blocking infection -- at least, in the lab, so far. Tao explains, "If we can find its natural enemy, we can control the spread of HIV naturally and cost-effectively, just as we use cats to control mice." Since Tao's work has not been tested outside of the laboratory, the HIV research community has refrained from premature celebration. Tao is using the concept of probiotic foods, e.g., foods such as yogurt which contain beneficial bacteria, to deal with the even more serious infection of HIV. From oral hygiene, we know that cavities or dental caries are caused by bacteria normally present in our mouth converting the sugar and starch left upon our teeth into enamel dissolving acid beginning within 20 minutes after the last meal or snack, so we brush our teeth, use an antiseptic mouth rinse, and floss to deprive the bacteria of their meal, and thus aid in the prevention of cavities. Using this principle of bacteria's attraction to sugar, Tao said, "Different bacteria have different sugar preferences. To block HIV, however, we needed to find bacteria that prefer the unusual sugar mannose and thus can capture it." Clinical trials are planned. Journalist Rowan Hooper points out in this article that: (1) This HIV-capturing lactobacillus is welcome, though an HIV vaccine would be better, (2) "It would be safe and easy to use," (3) An anti-HIV bacterium would provide "broad spectrum" protection against all subtypes of HIV (unlike a vaccine), (4) It could protect infants from contracting HIV from breast milk, (5) It could protect women against sexual transmission of HIV, despite a failure to use a condom, and (6) Possibly, most important of all, an HIV-capturing bacterium would be relatively inexpensive to develop, i.e., "The developmental cost for a vaccine is about $100 million to $1 billion," said Tao, "but a probiotic may only cost a few million."