Ahmad Hala, Alatshan Ahmad, Bíró Eduárd, Benkő Szilvia
Laboratory of Inflammation-Physiology, Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary.
Doctoral School of Molecular Cell and Immune Biology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary.
Front Immunol. 2025 Jul 1;16:1609763. doi: 10.3389/fimmu.2025.1609763. eCollection 2025.
Macrophages are indispensable in homeostasis and innate immune responses in multiple tissues, while their polarization and functional characteristics are determined by the activating stimuli and their tissue microenvironment. The vitamin A derivative retinoic acid shows inhomogeneous distribution among the tissues and has an important modulatory role in inflammatory responses. However, its effects on the cytokine secretion induced by the cytosolic pattern-recognition receptors NOD1 and NOD2 are unclear. In our study, we used human monocyte-derived macrophages differentiated in the presence of GM-CSF or M-CSF to generate inflammation inducing (GM-MФ) or inflammation resolving (M-MФ) cells, respectively. We activated the cells with either a NOD1- or NOD2 specific agonist and, using ELISA, we determined the pattern and dynamics of cytokines secreted by the macrophage subpopulations. Furthermore, we studied the effect of all-trans retinoic acid (ATRA) pre-treatment on the NOD1- and NOD2-induced cytokine release. Our comparative analysis shows subpopulation-characteristic pattern of cytokine secretion, as GM-MФ produce significantly higher pro-inflammatory IL-6, IL-8, TNF-α and IL-1β, while M-MФ secret higher anti-inflammatory IL-10. However, IL-18 and IFNβ secretion was comparable between the MФ subpopulations. We also show for the first time that ATRA has marked impact on cytokine secretion triggered by NOD1 and NOD2. Importantly however, the ATRA-induced changes of cytokine secretion follow opposite tendency in two MФ subpopulations. In conclusion, these results show that NOD1/NOD2-induced cytokine secretion by macrophage subsets is highly context-dependent and our results highlight the importance of the retinoic acid content of the local tissue environment in shaping macrophage function in health and disease.
巨噬细胞在多种组织的内环境稳态和固有免疫反应中不可或缺,而其极化和功能特性由激活刺激及其组织微环境决定。维生素A衍生物视黄酸在各组织中分布不均,在炎症反应中具有重要调节作用。然而,其对胞质模式识别受体NOD1和NOD2诱导的细胞因子分泌的影响尚不清楚。在我们的研究中,我们使用在GM-CSF或M-CSF存在下分化的人单核细胞衍生巨噬细胞,分别生成炎症诱导(GM-MФ)或炎症消退(M-MФ)细胞。我们用NOD1或NOD2特异性激动剂激活细胞,并使用酶联免疫吸附测定法(ELISA)确定巨噬细胞亚群分泌细胞因子的模式和动态。此外,我们研究了全反式视黄酸(ATRA)预处理对NOD1和NOD2诱导的细胞因子释放的影响。我们的比较分析显示了细胞因子分泌的亚群特征模式,因为GM-MФ产生显著更高的促炎细胞因子IL-6、IL-8、TNF-α和IL-1β,而M-MФ分泌更高的抗炎细胞因子IL-10。然而,IL-18和IFNβ在MФ亚群中的分泌相当。我们还首次表明,ATRA对由NOD1和NOD2触发的细胞因子分泌有显著影响。然而,重要的是,ATRA诱导的细胞因子分泌变化在两个MФ亚群中呈相反趋势。总之,这些结果表明,巨噬细胞亚群由NOD1/NOD2诱导的细胞因子分泌高度依赖于环境,我们的结果突出了局部组织环境中视黄酸含量在塑造健康和疾病状态下巨噬细胞功能方面的重要性。