CASP4 and chronic kidney disease: We first found that extracellular LPS binding protein HMGB1 was significantly increased in the kidneys of patients with CKD compared with healthy controls (Figure 6A), and higher expression levels of HMGB1 were inversely correlated with GFR (Figure 6B), suggesting that HMGB1-mediated LPS endocytosis is associated with CKD progression, presumably via increasing CASP4/11 activation.