Question

Which of the following blood group antigens serves as receptor for Plasmodium vivax?

• A. Duffy
• B. ABO
• C. Kell
• D. Rh

Hint:

Duffy negative red cells resist P. vivax invasion.

Answer 1

The Correct Option is A

Step 1: Understanding the Question.
The question asks which red cell surface antigen lets Plasmodium vivax merozoites get into the red blood cell.

Step 2: Key Concept.
Plasmodium vivax needs a specific docking point on the red cell membrane before it can invade. This docking point is the Duffy blood group antigen, also called the Duffy antigen receptor for chemokines (DARC).

Step 3: Detailed Explanation.
People who lack the Duffy antigen on their red cells, a trait common in West African populations, are naturally resistant to P. vivax infection because the parasite cannot attach and enter the cell. The ABO system decides blood transfusion compatibility and has no role in vivax entry. Kell and Rh antigens are also used for transfusion matching and for hemolytic disease of the newborn, but neither one is the entry point for this parasite.

Step 4: Final Answer.
The receptor P. vivax uses to enter red cells is the Duffy antigen.