Which type of cell does HIV primarily infect?

Which type of cell does HIV primarily infect?

• A. Red blood cells
• B. CD4+ T lymphocytes
• C. Neutrophils
• D. B lymphocytes

Answer: (B)

HIV primarily targets CD4+ T lymphocytes, which are a crucial component of the immune system. These cells play a significant role in the body's adaptive immune response by helping to activate other immune cells, including B cells and cytotoxic T cells. The infection process begins when the virus binds to the CD4 receptor on the surface of these T lymphocytes, facilitating viral entry into the cell. Once inside, HIV hijacks the cellular machinery to replicate and produce more copies of the virus, ultimately leading to a decline in CD4+ T cell counts, which severely weakens the immune system and can progress to AIDS if left untreated. In contrast, red blood cells are primarily responsible for oxygen transport and do not have the necessary receptors for HIV entry. Neutrophils are part of the innate immune system and generally respond to bacterial infections, while B lymphocytes are responsible for antibody production but are not the primary targets of HIV. This specificity of HIV for CD4+ T lymphocytes is key to understanding its mode of action and the resulting immunocompromised state in infected individuals.

HIV primarily targets CD4+ T lymphocytes, which are a crucial component of the immune system. These cells play a significant role in the body's adaptive immune response by helping to activate other immune cells, including B cells and cytotoxic T cells. The infection process begins when the virus binds to the CD4 receptor on the surface of these T lymphocytes, facilitating viral entry into the cell. Once inside, HIV hijacks the cellular machinery to replicate and produce more copies of the virus, ultimately leading to a decline in CD4+ T cell counts, which severely weakens the immune system and can progress to AIDS if left untreated.

In contrast, red blood cells are primarily responsible for oxygen transport and do not have the necessary receptors for HIV entry. Neutrophils are part of the innate immune system and generally respond to bacterial infections, while B lymphocytes are responsible for antibody production but are not the primary targets of HIV. This specificity of HIV for CD4+ T lymphocytes is key to understanding its mode of action and the resulting immunocompromised state in infected individuals.