Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil; Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil; Rheumatology Group, Centre for Inflammatory Diseases, School of Clinical Sciences at Monash Health, Monash University, Victoria, Australia.
Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil; Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.
Pharmacol Res. 2020 Aug;158:104842. doi: 10.1016/j.phrs.2020.104842. Epub 2020 May 13.
Macrophages are professional phagocytes that display remarkable plasticity, with a range of phenotypes that can be broadly characterized by the M1/M2 dichotomy. Glucocorticoid (GC)-induced leucine zipper (GILZ) is a protein known to mediate anti-inflammatory and some pro-resolving actions, including as neutrophil apoptosis. However, the role of GILZ in key macrophage function is not well understood. Here, we investigated the role of GILZ on macrophage reprogramming and efferocytosis. Using murine bone-marrow-derived macrophages (BMDMs), we found that GILZ was expressed in naive BMDMs and exhibited increased expression in M2-like macrophages (IL4-differentiated). M1-like macrophages (IFN/LPS-differentiated) from GILZ mice showed higher expression of the M1 markers CD86, MHC class II, iNOS, IL-6 and TNF-α, associated with increased levels of phosphorylated STAT1 and lower IL-10 levels, compared to M1-differentiated cells from WT mice. There were no changes in the M2 markers CD206 and arginase-1 in macrophages from GILZ mice differentiated with IL-4, compared to cells from WT animals. Treatment of M1-like macrophages with TAT-GILZ, a cell-permeable GILZ fusion protein, decreased the levels of CD86 and MHC class II in M1-like macrophages without modifying CD206 levels in M2-like macrophages. In line with the in vitro data, increased numbers of M1-like macrophages were found into the pleural cavity of GILZ mice after LPS-injection, compared to WT mice. Moreover, efferocytosis was defective in the context of GILZ deficiency, both in vitro and in vivo. Conversely, treatment of LPS-injected mice with TAT-GILZ promoted inflammation resolution, associated with lower numbers of M1-like macrophages and increased efferocytosis. Collectively, these data indicate that GILZ is a regulator of important macrophage functions, contributing to macrophage reprogramming and efferocytosis, both key steps for the resolution of inflammation.
巨噬细胞是专业的吞噬细胞，具有显著的可塑性，其表型范围可以广泛地分为 M1/M2 二分法。糖皮质激素（GC）诱导的亮氨酸拉链（GILZ）是一种已知介导抗炎和一些促解决作用的蛋白质，包括中性粒细胞凋亡。然而，GILZ 在关键巨噬细胞功能中的作用尚不清楚。在这里，我们研究了 GILZ 对巨噬细胞重编程和吞噬作用的作用。使用鼠骨髓来源的巨噬细胞（BMDM），我们发现 GILZ 在幼稚 BMDM 中表达，并在 M2 样巨噬细胞（IL4 分化）中表达增加。与 WT 小鼠分化的 M1 样巨噬细胞相比，GILZ 小鼠的 M1 样巨噬细胞（IFN/LPS 分化）表现出更高的 M1 标志物 CD86、MHC 类 II、iNOS、IL-6 和 TNF-α的表达，与磷酸化 STAT1 水平升高和 IL-10 水平降低相关。与 WT 动物的细胞相比，GILZ 小鼠来源的 IL-4 分化的巨噬细胞中 M2 标志物 CD206 和精氨酸酶-1 没有变化。用 TAT-GILZ（一种细胞通透性 GILZ 融合蛋白）处理 M1 样巨噬细胞可降低 M1 样巨噬细胞中 CD86 和 MHC 类 II 的水平，而不改变 M2 样巨噬细胞中的 CD206 水平。与体外数据一致，在 LPS 注射后，GILZ 小鼠的胸腔中发现更多的 M1 样巨噬细胞，而 WT 小鼠则较少。此外，在 GILZ 缺陷的情况下，吞噬作用受损，无论是在体外还是体内。相反，用 TAT-GILZ 处理 LPS 注射的小鼠可促进炎症消退，与较少的 M1 样巨噬细胞和增加的吞噬作用相关。总之，这些数据表明 GILZ 是重要巨噬细胞功能的调节剂，有助于巨噬细胞重编程和吞噬作用，这两者都是炎症消退的关键步骤。
