CCR2 and triple-A syndrome: Single cell RNAseq analysis of elastase-driven AAA and healthy vessels revealed that CX3CR1+ (yolk-sac derived) macrophages are the most abundant subset in healthy aorta representing 62.5% of total macrophage population, while bone marrow derived macrophages (CCR2+Ly6C2lowF4/80lowCD11blowH2-Aalow) start to dominate in AAA lesions (107).