Question

What does HIV do to the human immune system?

Short answer

HIV attacks and destroys the body's CD4+ T-cells, key players in the immune system, leading to a weakened immune system which is more susceptible to infections and diseases.

Step-by-step solution

Understand the introduction of HIV in the body

When HIV enters the human body, it first targets and latches onto the CD4+ T-cells, which are a type of white blood cells that play a key role in the body's immune response. More particularly, HIV binds with the CD4 receptors on the membrane of these cells.

Describe the replication of HIV

Once the virus is attached to the CD4+ T-cell, HIV fuses with the cell. The virus then releases its viral RNA material into the cell and uses an enzyme called reverse transcriptase to convert this viral RNA into DNA. This new DNA is integrated into the cell's DNA with the help of another enzyme called integrase. Now, the cell not only produces its own proteins but also the proteins required to make new HIV.

Explain the consequences of HIV replication

Each infected cell can produce thousands of new HIV particles, which are released into the bloodstream and then infect other CD4+ T-cells. Over time, HIV depletes the number of CD4+ cells, weakening the immune system.

Highlight the outcome

As the immune system weakens, the body becomes more susceptible to infections and diseases. This leads to the onset of acquired immune deficiency syndrome (AIDS), the most severe phase of HIV infection.