A step in the right direction…HIV vaccine research

Rachel Corrado- Boston University student and BLC Volunteer

As a health science student at Boston University, I am always excited when the lectures in my classes relate to the topics I hear about in the BLC. Lately, I was assigned to read an article dealing with new progress made in developing a possible vaccine for HIV. Researchers at Oxford University have recently discovered aspects of the virus’ protective structure that may actually make it vulnerable.

At its most basic level, HIV is a bundle of proteins and carbohydrates. While most attempts at vaccine development have been focusing on the proteins, this method has so far been unsuccessful. HIV always seems to be one step ahead of the body’s immune system, mutating and shifting its proteins so that developing an effective antibody is extremely difficult. However, Dunlop et. al. have made some interesting discoveries by taking a closer look at the carbohydrate portion of the structure.

“Most of the antigenic surface of HIV is covered by carbohydrates,” says Dr. Christopher Scanlan, one of the researchers involved in the project. “It’s often called the glycan shield. The virus needs to be continually evading the immune system, and this shield is perhaps the most effective strategy.”

This “glycan shield” acts as a sort of cloaking device as the virus makes its way through the body, hiding it from the immune system. Normally, it is one of HIV’s primary means of protecting itself, but the scientists think they may have discovered a flaw in this armor that they might be able to turn against the virus. The structure is unique in that the surface carbohydrates are packed so closely together, and while this makes the defense mechanism effective, it also prevents the typical modification that would normally occur in other viruses. In other words, the researchers have found a stable portion of HIV for the body’s immune system to recognize and latch onto. Furthermore, they discovered that certain carbohydrates that coat the outside of yeast cells are remarkably similar to the stable carbohydrates on the outside of HIV. If the researchers can modify the yeast carbohydrates to look more like the ones on HIV, they may be able to create a safe and effective vaccine.

Though it may just be because I am a biology nerd, I love it when I can learn about all the mechanics of the human body and how it interacts with the diseases to which it is exposed. It’s even better when I can learn about something like this, which may be a step in the right direction for finally developing a tool to fight this dangerous and adaptive virus.

Article:

“Polysaccharide mimicry of the epitope of the broadly neutralizing anti-HIV antibody, 2G12, induces enhanced antibody responses to self oligomannose glycans.” Dunlop, D.C. et. al. Glycobiology 2010.

The BLC would like to thank Rachel Corrado for her contribution to our blog and her continued service to the HIV community.

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National Women and Girls HIV/AIDS Awareness Day

This article is authored by Rachel Corrado- Boston University Student and BLC Volunteer

 

Being that March 10th is National Women and Girls HIV/AIDS Awareness Day, the spotlight is currently being focused on woman-specific methods of treatment and prevention across the country. While this is an American event, it offers a good opportunity to think also of women across the world who are fighting against this virus, especially those living on the continent in which the front lines of this epidemiological war are located.

 Out of more than 33 million people living with HIV and AIDS worldwide, women account for about 52%. In sub-Saharan Africa, however, the scales are tipping. There, 60% of those fighting against this disease are women and girls. Because of their biology, women are at a higher risk of contracting HIV in the first place. Circumstances in many parts of Africa are exacerbating this imbalance and making things especially difficult for those hoping to control the spread of the virus, as illustrated by the story of Mma Oganne.

Mma was a married mother of four when she tested for HIV. She did not even believe that the disease existed before she was diagnosed, let alone consider that she was at risk. Because she lived in rural Botswana, this may have been a result of a lack of education in the area. Another troubling possibility, however, is that she believed the theories of AIDS denialists such as former South African president Thabo Mbeki, who insist that HIV does not lead to AIDS and can be cured by home remedies such as lemon, garlic, and olive oil. Some others say that AIDS does not exist at all, or denounce life-saving antiretroviral drugs as poison and claim that they cause, rather than treat, AIDS. 

When two of her children were consistently sickly and frail, Mma took them to a health clinic where all three of them tested positive. Her husband’s reaction to the news then added insult to injury; he told her that he was going to get tested and never came back home. Even more unfair is the fact that he was almost certainly the one to infect her. Mma’s husband is a mineworker, currently one of Africa’s populations at the highest risk of contracting HIV. Mineworkers often are away from home for long periods of time, sometimes in different countries altogether. Many of them have relationships with women living near the mines where they work and end up bringing STIs back home with them. This is likely the situation with Mma, who then passed the disease on to her children when they were born.

The bright spot in this story is that Mma was able to obtain antiretroviral drugs for her children. For many people, there is no clinic close enough to visit on a regular basis in order to obtain the medicine. For others, the medicine is available nearby, but they do not have the money to pay for it. At first, she refused to take the drugs for fear of alienating herself from the community. The stigma of having AIDS in much of Africa is so powerful that most refuse even to get tested to avoid suspicion. Once she saw the dramatic change in her children’s health, however, she rethought her decision.

 Being HIV positive is enough to handle without such large societal problems making things worse. Issues like social stigma, lack of access to care, the spread of inaccurate information, and so many others are tying the hands of people trying to make things better in Africa. Big changes need to made in places like Botswana, especially for women like Mma, if the spread of HIV is ever going to be controlled. This is something to think about on Women and Girls HIV/AIDS Awareness Day while people the world over are fighting to gain ground in the struggle against this disease.

http://www.unaids.org/en/strategygoalsby2015/womenandgirls/

 http://www.pbs.org/wgbh/rxforsurvival/series/video/botswana1_qt_h.html

http://www.nytimes.com/2006/06/04/opinion/04moore.html

http://baywood.metapress.com/app/home/contribution.asp?referrer=parent&backto=issue,10,12;journal,81,161;linkingpublicationresults,1:300313,1

The BLC would like to thank Rachel Corrado for her contribution to our blog, and her ongoing volunteer efforts to serve people living with HIV.