RIPK3 deficiency or catalytically inactive RIPK1 provides greater benefit than MLKL deficiency in mouse models of inflammation and tissue injury

Cell Death Differ. 2016 Sep 1;23(9):1565-76. doi: 10.1038/cdd.2016.46. Epub 2016 May 13.


Necroptosis is a caspase-independent form of cell death that is triggered by activation of the receptor interacting serine/threonine kinase 3 (RIPK3) and phosphorylation of its pseudokinase substrate mixed lineage kinase-like (MLKL), which then translocates to membranes and promotes cell lysis. Activation of RIPK3 is regulated by the kinase RIPK1. Here we analyze the contribution of RIPK1, RIPK3, or MLKL to several mouse disease models. Loss of RIPK3 had no effect on lipopolysaccharide-induced sepsis, dextran sodium sulfate-induced colitis, cerulein-induced pancreatitis, hypoxia-induced cerebral edema, or the major cerebral artery occlusion stroke model. However, kidney ischemia-reperfusion injury, myocardial infarction, and systemic inflammation associated with A20 deficiency or high-dose tumor necrosis factor (TNF) were ameliorated by RIPK3 deficiency. Catalytically inactive RIPK1 was also beneficial in the kidney ischemia-reperfusion injury model, the high-dose TNF model, and in A20(-/-) mice. Interestingly, MLKL deficiency offered less protection in the kidney ischemia-reperfusion injury model and no benefit in A20(-/-) mice, consistent with necroptosis-independent functions for RIPK1 and RIPK3. Combined loss of RIPK3 (or MLKL) and caspase-8 largely prevented the cytokine storm, hypothermia, and morbidity induced by TNF, suggesting that the triggering event in this model is a combination of apoptosis and necroptosis. Tissue-specific RIPK3 deletion identified intestinal epithelial cells as the major target organ. Together these data emphasize that MLKL deficiency rather than RIPK1 inactivation or RIPK3 deficiency must be examined to implicate a role for necroptosis in disease.

MeSH terms

  • Animals
  • Apoptosis / drug effects
  • Ceruletide / toxicity
  • Colitis / chemically induced
  • Colitis / metabolism
  • Colitis / pathology
  • Dextran Sulfate / toxicity
  • Disease Models, Animal
  • Female
  • Inflammation / metabolism
  • Inflammation / pathology*
  • Lipopolysaccharides / toxicity
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Pancreatitis / chemically induced
  • Pancreatitis / metabolism
  • Pancreatitis / pathology
  • Protein Kinases / deficiency
  • Protein Kinases / genetics*
  • Protein Kinases / metabolism
  • Receptor-Interacting Protein Serine-Threonine Kinases / antagonists & inhibitors
  • Receptor-Interacting Protein Serine-Threonine Kinases / deficiency
  • Receptor-Interacting Protein Serine-Threonine Kinases / genetics*
  • Receptor-Interacting Protein Serine-Threonine Kinases / metabolism*
  • Reperfusion Injury / metabolism
  • Reperfusion Injury / mortality
  • Reperfusion Injury / pathology
  • Sepsis / etiology
  • Sepsis / metabolism
  • Sepsis / pathology
  • Systemic Inflammatory Response Syndrome / etiology
  • Systemic Inflammatory Response Syndrome / metabolism
  • Systemic Inflammatory Response Syndrome / pathology
  • Tumor Necrosis Factor alpha-Induced Protein 3 / deficiency
  • Tumor Necrosis Factor alpha-Induced Protein 3 / genetics


  • Lipopolysaccharides
  • Ceruletide
  • Dextran Sulfate
  • MLKL protein, mouse
  • Protein Kinases
  • Receptor-Interacting Protein Serine-Threonine Kinases
  • Ripk1 protein, mouse
  • Ripk3 protein, mouse
  • Tumor Necrosis Factor alpha-Induced Protein 3
  • Tnfaip3 protein, mouse