Spalinger Marianne R, Kasper Stephanie, Gottier Claudia, Lang Silvia, Atrott Kirstin, Vavricka Stephan R, Scharl Sylvie, Raselli Tina, Frey-Wagner Isabelle, Gutte Petrus M, Grütter Markus G, Beer Hans-Dietmar, Contassot Emmanuel, Chan Andrew C, Dai Xuezhi, Rawlings David J, Mair Florian, Becher Burkhard, Falk Werner, Fried Michael, Rogler Gerhard, Scharl Michael
J Clin Invest. 2016 May 2;126(5):1783-800. doi: 10.1172/JCI83669. Epub 2016 Apr 4.
Inflammasomes form as the result of the intracellular presence of danger-associated molecular patterns and mediate the release of active IL-1β, which influences a variety of inflammatory responses. Excessive inflammasome activation results in severe inflammatory conditions, but physiological IL-1β secretion is necessary for intestinal homeostasis. Here, we have described a mechanism of NLRP3 inflammasome regulation by tyrosine phosphorylation of NLRP3 at Tyr861. We demonstrated that protein tyrosine phosphatase non-receptor 22 (PTPN22), variants in which are associated with chronic inflammatory disorders, dephosphorylates NLRP3 upon inflammasome induction, allowing efficient NLRP3 activation and subsequent IL-1β release. In murine models, PTPN22 deficiency resulted in pronounced colitis, increased NLRP3 phosphorylation, but reduced levels of mature IL-1β. Conversely, patients with inflammatory bowel disease (IBD) that carried an autoimmunity-associated PTPN22 variant had increased IL-1β levels. Together, our results identify tyrosine phosphorylation as an important regulatory mechanism for NLRP3 that prevents aberrant inflammasome activation.
炎性小体是由细胞内存在的危险相关分子模式形成的,并介导活性白细胞介素-1β(IL-1β)的释放,IL-1β会影响多种炎症反应。炎性小体过度激活会导致严重的炎症状态,但生理性IL-1β分泌对于肠道稳态是必要的。在此,我们描述了一种通过NLRP3第861位酪氨酸磷酸化来调节NLRP3炎性小体的机制。我们证明,蛋白酪氨酸磷酸酶非受体22(PTPN22)(其变体与慢性炎症性疾病相关)在炎性小体诱导时使NLRP3去磷酸化,从而使NLRP3有效激活并随后释放IL-1β。在小鼠模型中,PTPN22缺陷导致明显的结肠炎、NLRP3磷酸化增加,但成熟IL-1β水平降低。相反,携带与自身免疫相关的PTPN22变体的炎症性肠病(IBD)患者的IL-1β水平升高。总之,我们的结果确定酪氨酸磷酸化是NLRP3的一种重要调节机制,可防止炎性小体异常激活。