State Key Laboratory of Trauma, Burns and Combined Injury, Department of Wound Infection and Drug, Daping Hospital, Army Medical University, Chongqing, China; Department of Intensive Care Unit, The Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou, China.
State Key Laboratory of Trauma, Burns and Combined Injury, Department of Wound Infection and Drug, Daping Hospital, Army Medical University, Chongqing, China.
Cytokine. 2020 Apr;128:155001. doi: 10.1016/j.cyto.2020.155001. Epub 2020 Feb 5.
Neutrophilic granule protein (NGP) belongs to the cystatin superfamily. Even though this superfamily is critically involved in cancer biology and adaptive immunity, the relationship of macrophage NGP to inflammation and phagocytosis remains poorly understood. In this study, we observed a significant increase of NGP in peritoneal macrophages (PMs) isolated from mice challenged with E. coli or lipopolysaccharide (LPS), as judged by NGP mRNA microarray. We also found changes in NGP to be mainly Toll-like receptor 4 (TLR4)-dependent. By western blot and electrophoretic mobility shift assay, we demonstrated NGP overexpression to reduce TNF-α and IL-1β production by LPS-induced RAW264.7 cells (RAW) via suppression of the NF-κB (p65 and p50) signalling pathway, rather than the JNK1/AP-1 (fos and jun) signalling pathway. NGP overexpression by LPS-induced RAW also induced IL-10, an anti-inflammatory cytokine, which was partially involved in the anti-inflammatory effect produced by NGP overexpression. Moreover, upregulated NGP enhanced the phagocytosis of E. coli by RAW. Taken together, these results demonstrated NGP to be an important host defense component that regulates inflammatory responses and phagocytosis by activated macrophages. As such, NGP may be useful for the treatment of inflammatory based disease.
中性粒细胞颗粒蛋白 (NGP) 属于半胱氨酸蛋白酶抑制剂超家族。尽管该超家族在癌症生物学和适应性免疫中起着至关重要的作用，但巨噬细胞 NGP 与炎症和吞噬作用的关系仍知之甚少。在这项研究中，我们通过 NGP mRNA 微阵列观察到，用大肠杆菌或脂多糖 (LPS) 刺激的小鼠分离的腹腔巨噬细胞 (PM) 中 NGP 的显著增加。我们还发现 NGP 的变化主要依赖于 Toll 样受体 4 (TLR4)。通过 Western blot 和电泳迁移率变动分析，我们证明 NGP 的过表达通过抑制 NF-κB（p65 和 p50）信号通路，而不是 JNK1/AP-1（fos 和 jun）信号通路，来减少 LPS 诱导的 RAW264.7 细胞 (RAW) 中 TNF-α和 IL-1β的产生。LPS 诱导的 RAW 中的 NGP 过表达也诱导了抗炎细胞因子 IL-10 的产生，这部分参与了 NGP 过表达产生的抗炎作用。此外，上调的 NGP 增强了 RAW 对大肠杆菌的吞噬作用。总之，这些结果表明 NGP 是一种重要的宿主防御成分，可调节激活的巨噬细胞中的炎症反应和吞噬作用。因此，NGP 可能可用于治疗基于炎症的疾病。
