ADAM protease activationin the context of IL-6R biology

白介素6(IL-6)转导信号是通过IL-6和可溶性IL-6受体(sIL-6R)介导的。在病理生理条件下，IL-6转导信号上调。在人类中，ADAM17是IL-6R的主要脱落酶。我们最近的数据表明，在小鼠中，IL-6R的脱落主要是由ADAM10介导的，而ADAM17只有少量的作用。这种独特的物种特异性差异将被研究以确定蛋白酶-底物识别和IL-6R脱落的调节模式。ADAM17的底物有70多种，包括TNFa和EGFR配体。只有在例外情况下，减少或增加单一底物的脱落才能在ADAM缺陷或转基因小鼠中进行研究。我们开发了不依赖于ADAM-Protease活性的新的小鼠遗传策略，以分析体内1L-6R胞外区的去除和增强。在sgp130Fc转基因小鼠中。IL-6-转导信号而不是IL-6经典信号被阻断，这模拟了1L-6R的ADAM缺陷。新的仅有sIL-6R的GFP报告条件敲击的特异性Cre重组将导致小鼠sIL-6R表达增加而细胞IL-6R水平降低，从而模拟1L-6R的ADAM过度激活。此外，IL-6R与GFP基因连锁，跟随IL-6R在体内的生物学表达背景下的ADAM蛋白酶激活。这些小鼠品系将全面表征IL-6反式信号在炎症状态中的作用。

Interleukin 6 (IL-6) trans-signaling is mediated via IL-6 and the soluble IL-6 Receptor (slL-6R). lL-6 transsignaling was found to be upregulated under pathophysiological situations. In humans, ADAM17 is the main sheddase of IL-6R. Our recent data show that in mice shedding of the IL-6R is largely me-diated by ADAM10 and only to a minor extend by ADAM17. This unique species-specific difference will be studied to define protease-substrate recognition and regulation patterns of IL-6R shedding. More than 70 substrates of ADAM17 were described including TNFa and EGFR-ligands. Only In ex-ceptional cases, reduced or increased shedding of a single substrate can be studied in ADAM defi-cient or transgenic mice. We developed novel mouse genetic strategies independent on ADAM pro-tease activity to analyze abrogated and enhanced 1L-6R ectodomain shedding in vivo. In sgp130Fc transgenic mice. IL-6-transsignaling but not IL-6 classic signaling is blocked, which mimics ADAM deficiency for 1L-6R. Tissuespecific Cre-recombination of the novel slL-6R-only GFP-reporter condi-tional Knock In mice will lead to mice expressing increased slL-6R but reduced cellular IL-6R level, thereby mimicking ADAM hyperactivation for 1L-6R. Furthermore, the IL-6R was genetically linked to GFP to follow IL-6R ADAM protease activation in the context of tL-6R biology expression in vivo. These mouse lines will comprehensively characterize the role of lL-6 trans-signaling in inflammatory states.