引用

先前的研究表明G(i)蛋白作为toll样受体(TLR)激活的协同调节因子。这些研究主要来源于对G(i)蛋白抑制剂或G(i)蛋白基因缺失的影响的检测。然而，G(i)蛋白功能或G(i)蛋白表达增加对TLR激活的影响尚未被研究。我们假设G(i)蛋白的功能增强或表达增加会抑制TLR2-和tlr4诱导的炎症细胞因子。基因敲入G蛋白信号调节因子(RGS)不敏感基因Gnai2等位基因(G(i2)(G184S/G184S)的新型转基因小鼠;GS/GS)被雇用。这些小鼠表达基本正常水平的G(i2)蛋白;然而，G(i2)对其负调控因子RGS不敏感，因此在配体/受体结合后，G(i2)蛋白激活更持久。在后续的研究中，我们生成了稳定过表达G(i2)蛋白的Raw 264.7细胞(Raw G(i2))。从WT和GS/GS小鼠中分离出腹腔巨噬细胞、脾细胞和小鼠胚胎成纤维细胞(MEF)，并用LPS、Pam3CSK4或Poly (I:C)刺激。 We also subjected WT and GS/GS mice to endotoxic shock (LPS, 25 mg/kg i.p.) and plasma tumor necrosis factor alpha (TNF-) and interleukin (IL)-6 production were determined. We found that in vitro LPS and Pam3CSK4-induced TNF-, and IL-6 production are decreased in macrophages from GS/GS mice compared with WT mice (p<0.05). In vitro, LPS and Pam3CSK4 induced IL-6 production in splenocytes, and in vivo, LPS-induced IL-6 were suppressed in GS/GS mice. Poly (I:C)-induced TNF-, and IL-6 in vitro demonstrated no difference between GS/GS mice and WT mice. LPS-induced IL-6 production was inhibited in MEFs from GS/GS mice similarly to macrophage and splenocytes. In parallel studies, Raw G(i2) cells also exhibit decreased TNF- and IL-6 production in response to LPS and Pam3CSK4. These studies support our hypothesis that G(i2) proteins are novel negative regulators of TLR activation.