Question

HIV causes reduction of:

• A. T-helper cells only
• B. All T-cells
• C. B-cells only
• D. Both B and T-cells

Hint:

Remember: \[ \text{HIV} \rightarrow \text{CD4}^{+}\text{ T-helper cells} \] \[ \text{AIDS} = \text{Acquired Immunodeficiency Syndrome} \] A decrease in CD4\(^+\) T-helper cells is the hallmark of HIV infection.

Answer 1

The Correct Option is A

Step 1: Recall the target cells of HIV. HIV (Human Immunodeficiency Virus) primarily infects: \[ \boxed{\text{T-helper lymphocytes (CD4}^{+}\text{ cells)}} \] These cells play a crucial role in coordinating the immune response.

Step 2: Understand the effect of HIV infection. As HIV multiplies inside T-helper cells, it gradually destroys them. This leads to: \[ \text{Progressive decline in CD4}^{+}\text{ T-helper cells} \] and weakens the immune system.

Step 3: Evaluate the options.
• T-helper cells only \(\rightarrow\) Correct \(\checkmark\)
• All T-cells \(\rightarrow\) HIV specifically targets CD4\(^+\) T-helper cells \(\times\)
• B-cells only \(\rightarrow\) Not the primary target \(\times\)
• Both B and T-cells \(\rightarrow\) Incorrect \(\times\) Therefore, \[ \boxed{\text{T-helper cells only}} \] Hence, the correct answer is: \[ \boxed{\text{(A)}} \]