. At first, you may think that this is a subject that only doctors and medical students need to understand.
But if you or someone you are caring for is HIV+, it is important for you to know the facts as well. Knowing how HIV works in the body can help you to have a more informed talk with the doctor about HIV and can help you understand why treatment is so important. The following presentation will give you the knowledge you need to understand how HIV works in the body.
- HIV invades healthy cells in your body—like all viruses, HIV cannot live on its own. So, HIV has to invade a healthy cell in the body in order to survive. Just as you have a favorite flavor of ice cream or a favorite color, HIV has a favorite type of cell it likes to invade. These cells are called CD4 cells. These special CD4 cells work like a factory in the body that makes special chemicals to fight off infection and keep you from getting sick.
- HIV has the key to unlock a CD4 cell—it is important to think of CD4 cell as having a "lock" to protect them from invaders. Unfortunately, HIV has the "key." This key lets HIV get into the CD4 cells. This key is found on the surface of the HIV and opens the CD4 cell for invasion and infection by HIV.
- HIV gets into the command center—just as you might have a locked cabinet in your house to store important papers or valuable items, a CD4 cell has another lock that protects the command center or "brain" of the cell. However, HIV has another set of "keys" in the form of proteins called "reverse transcriptase." Despite the fancy name, these proteins have a function that is easy to understand. They disguise HIV as a normal CD4 cell "worker" and allow HIV to enter the command center of the cell.
- The command center of the CD4 cell protects the body by producing different substances or chemicals that fight off infection and destroy germs, bacteria, and other viruses. But HIV is sneaky! It uses another protein called an "integrase" so that it "fits in" in the command center. By using this protein, HIV tricks the CD4 cell into thinking that it is a normal part of the CD4 command center. So, HIV becomes part of the CD4 command center without the cell even realizing it!
- HIV becomes the boss—after HIV has tricked the CD4 cell into letting it into the command center, HIV now works to take control of the CD4 cell. HIV hijacks the CD4 cell by inserting its own instructions into the command center. These new instructions command the CD4 cell to make more copies of HIV.
- The CD4 cell becomes an HIV factory—at this point, the CD4 cell has been changed into an HIV factory. HIV is in the command center and has become the boss. The CD4 cell now works to make new copies of different parts of HIV. Another HIV protein then works to cut out these new parts and puts them together into new copies of HIV. These new copies of HIV leave the CD4 command center and seek out other CD4 cells to invade and take over.
Now that you understand how HIV works, let's explore how the 3 different types of HIV medications work to help stop HIV in its tracks. In general, all 3 types of HIV medication work by blocking HIV proteins at different points during invasion of the CD4 cell:
- NRTIs (nucleoside reverse transcriptase inhibitors) and NNRTIs (nonnucleoside reverse transcriptase inhibitors)—these drugs stop HIV from using the protein "keys" to get into the CD4 command center. Since HIV is unable to get into the command center, it cannot make new copies of itself
- PIs (protease inhibitors)—this type of drug stops the protein responsible for cutting out newly made HIV parts and assembling the newly made copies of HIV. This drug prevents the protein from putting the newly formed parts together correctly. As a result, the newly formed copies of HIV do not work
- FIs (fusion inhibitors)—this type of drug prevents HIV from entering the cell
One final note—while these drugs have made a significant difference by allowing millions of people to live longer and more productive lives with HIV, it is important to realize that none of these drugs is a cure. None of these drugs gets rid of all the HIV in your body. That is why it is important to not only know how HIV and anti-HIV medications work, but it is also important to know how to prevent HIV infection.
