In chronic inflammation at a site of tissue injury, circulating monocytes are recruited out of blood and into tissue. Which chemokine receptor ligand pair primarily directs this recruitment?

• A CCR2 with CCL2 ✓
• B CCR7 with CCL19
• C CXCR4 with CXCL12
• D CXCR2 with CXCL8

Explanation

Monocytes express CCR2, and tissue macrophages, endothelium and fibroblasts secrete its ligand CCL2 (MCP-1), making this axis the dominant pathway for monocyte recruitment in chronic inflammation. CXCR4 with CXCL12 retains hematopoietic cells in bone marrow, CCR7 guides naive T cells and dendritic cells to lymph nodes, and CXCR2 with CXCL8 (IL-8) attracts neutrophils, which explains why those pairs are incorrect for monocyte homing.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.