For instance, IL-6, IL-8, pentraxin-3, neutrophil gelatinase-associated lipocalin (NGAL), calprotectin or tumor necrosis factor (TNF)-α were significantly higher in PAD patients compared with healthy controls [14,21,22,23,24,33,34], and some of these candidates; IL-6, TNF-α, and pentraxin-3 were associated to PAD severity, assessed either by ABI or clinical scales [21,23,52]. The gene discussed is LCN2; the disease is peripheral arterial disease.