One of the most persistent myths about the HIV epidemic is that the government (or the other perceived villain-pharmaceutical companies) have discovered a cure but that, for whatever reasons, have not made it available. This reasoning fails to take into account the complexity of vaccine development in general, not to mention the unique challenge of curing HIV. One of the crucial steps to finding a cure involves eradicating all of the virus from the body. Complicating this are stubborn reservoirs of HIV that remain in the body and seem out of reach of antiretroviral medication. These reservoirs consist of old CD4 cells that preserve latent HIV throughout the body, essentially storing, or 'archiving' it for decades. Therefore, even though antiretroviral medication may significantly reduce viral reproduction and clear the host of most HIV virus, they never completely purge HIV from the body. When the medication is interrupted or ceases its effectiveness, because of viral resistance, this reservoir can become reactivated, ensuring more viral replication and eventually, more illness. Therefore, the inability to eradicate HIV from the body has been the main stumbling block towards finding a cure.
However, recent developments by Dr. Robert Siliciano of Johns Hopkins University has brought new hope that HIV eradication may be achievable. Dr. Siliciano believe that there are two reservoirs of old (or latent) HIV, one that consists of what are called CD4 memory cells. These cells are created to combat various infections that we have developed, such as measles. HIV meds are only effective against cells infected with HIV that are active. However, activating all memory cells simultaneously can be dangerous. Therefore, the goal is to activate only those cells that are infected with HIV, so that the HIV meds can, in effect, take them out. Dr. Siliciano and group have found a handful of compounds that they believe may selectively activate HIV infected cells. The trick will be finding compounds that will be safe in humans.
Sound complicated? Well this is just a small glimpse of the work being done all over the world to either create a vaccine for HIV, or to find a cure. However, as this brief snapshot demonstrates, it is a very difficult, frustrating and costly endeavor. Therefore, we should be more appreciative of the efforts of researchers such as Dr. Siliciano and his colleagues or Michael Swanson, a doctoral student at the University of Michigan and his group who have discovered a lectin (naturally occurring chemicals in plants that bind to sugars on the surface of disease-causing microorganisms such as viruses) found in bananas, that might lead to the development of inexpensive microbicides to prevent HIV transmission or even new treatments.
In the meantime, while these dedicated researchers wage their own battle in laboratories around the world, we to must do out part to reduce HIV infection: Prevention.
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