The two urinary biomarkers TIMP-2 (tissue inhibitor of metalloproteinase 2; 21 kDa) and IGFBP7 (insulin-like growth factor-binding protein 7; 25 kDa) are secreted in the early phase of tubular damage (e.g., in the context of sepsis [50] or after ischemia [41]) by the proximal and distal tubular epithelial cells. Here, IGFBP7 is linked to ischemia.