The concurrence of NETs formation with Fn14 upregulation in septic AKI was further corroborated by co-immunofluorescence microscopy and western-blotting (WB) analyses showing that the steady-state levels of peptidylarginine deiminase 4 (PAD4), an arginine-citrullines conversion enzyme responsible for NETs release 25, were elevated in renal tissues of CLP mice together with the increased Fn14 expression per se (Figure 1D and S1F). This evidence concerns the gene PADI4 and acute kidney injury.