SBA — Single Best Answer · Review
Question 621
Immunology → General
Classification
Question
SSBAQuestion Header
A circulating phagocytic cell migrates into tissues and differentiates into a macrophage. Which circulating cell is its precursor?
Question Stem
Select the single best answer.
Options
A
Monocyte
B
Eosinophil
C
Basophil
D
Natural killer cell
E
B lymphocyte
Explanation
Circulating monocytes migrate into tissues where they differentiate into macrophages. Macrophages are important phagocytic cells and can be activated by interferon-gamma.
Option Validity
B) Eosinophils are granulocytes associated particularly with large parasites, allergy and antigen-antibody complexes.
C) Basophils are granulocytes and are not the circulating precursors of macrophages.
D) Natural killer cells are lymphocytes with spontaneous cytotoxic activity.
E) B lymphocytes are components of acquired humoral immunity.
Further Reading
Saxena MRCOG-1 Basic Sciences — Immunology: Phagocytic cells, printed page 211.