In addition, renal endothelial cells upregulate the expression of CX3CL1 (fractalkine), a ligand for the CX3CR1 receptor expressed on macrophages that mediates macrophage recruitment in the inflamed kidney, and pretreatment with a neutralizing CX3CR1 monoclonal antibody reduces the severity of acute kidney injury [47]. This evidence concerns the gene CX3CL1 and acute kidney injury.