The Effects of HIV on the Body
HIV is a fascinating disease because of the fact that you do not actually die from the disease itself; you die from another, potentially harmless, disease, which your body cannot protect against due to its weakened immune system. In order to understand this better, it is important to understand how HIV affects the body. HIV weakens the body’s immune system by attacking T4 lymphocytes, a type of white blood cell. These T4 helper cells are called this because they have a receptor molecule on their surface called, CD4.
The T4 cells don’t create antibody but they are responsible for chemically communicating, using chemokine, with other white blood cells in order to “launch an attack” on a virus. The HIV cells contain two viral proteins that are directly involved in the process of infecting someone, these proteins are called gp41 and gp120. The “CD4 on the surface of the T cell allows for the docking of gp120; once docked, the gp120 changes its shape so that it can bind to the chemokine receptor (called CCR5), and fusion and entry of HIV take place after binding. Sherman p. 178)” It is not known exactly how the viral proteins deplete T4 cells but it is believed to “involve a depression in the ability to expand their numbers. (Sherman p. 178)” Once the T4 cells reach 400 to 800 cells/mm^3, as opposed to the healthy 1,000 or more T4 cells/mm^3, the first opportunistic infections can arise. This refers to infections that would normally not cause a disease, or at least nothing life threatening, but given the bodies weakened immune system begins to cause serious health problems for the individual.
After this point things become dangerous, but can still be turned around, however if a persons T4 count reaches 200, they officially have AIDS. Once someone has gotten AIDS, there is little to nothing a doctor can do because their immune system is so damaged that they can barely fight off a cold. At this point the person’s immune system is so damaged that they could very easily die from something like pneumonia or meningitis. As the infected decline further they become more and more susceptible to disease and even something like herpes, which is almost always not fatal, can cause death.
Once a person reaches the 100 T4 cells/mm^3 mark there is no telling what could kill them, it could even be something as simple as a cold or influenza. The good news is that, although there are no cures for AIDS, there are some options for controlling HIV before it reaches the AIDS state. The first AIDS treatment, which is still used today, is an antitumor compound called azidothymidine (AZT). AZT was developed in 1964 by a pair of chemists-pharmacologists named George Hitchings and Gertrude Elion who had created several other antitumor drugs.
AZT works by delaying “the onset of AIDS by inhibiting viral multiplication…AZT jam’s the cell’s copier and, in do doing, blocks the synthesis of new virus particles. (Sherman p. 184)” There are several other drugs called nucleoside analogs that also block the synthesis of viral nucleic acids, and are generally used along with AZT to make the famous “drug cocktail. ” Another treatment option is a combination of protease inhibitors and reverse transcriptase inhibitors.
The protease inhibitors work by preventing the viral enzyme, protease, from cutting viral proteins into shorter pieces. If short viral proteins cannot be produced then a complete virus cannot be assembled. The reverse transcriptase inhibitors work by blocking viral replication. This combination of drugs is able to significantly reduce virus production, up to 90-99%. The only problem with these treatments is that they are expensive and need to be taken daily.
Although there is no cure for HIV/AIDS there is constant research being done on the possibility of creating some sort of vaccine that would be able to prevent HIV and, at least, slow the development of new HIV cell in those who are already infected. So far there have been some advancements but nothing has been created that would be effective or stable enough. That being said, the continuing efforts of the medical field and breakthroughs in treatment, we are moving closer and closer to the possibility of having some kind of vaccine and maybe someday a cure.