Department of Nutrition and Food Science, University of Maryland, College Park, MD, 20742, USA.
U.S. Department of Agriculture, Agricultural Research Service, Beltsville Human Nutrition Research Center, Diet, Genomics and Immunology Laboratory, Beltsville, MD, 20705, USA.
Sci Rep. 2023 Jul 7;13(1):11007. doi: 10.1038/s41598-023-37040-0.
To further elucidate the expression, regulation and function of Signaling Lymphocytic Activation Molecule Family (SLAMF) protein members in human monocytes and macrophages. Un-differentiated monocytic THP-1 cell (u-THP-1) and differentiated THP-1 macrophage (d-THP-1) were used as culture models in the study. Responses of cells to the differentiation agents phorbol ester (25 ng/ml) and TLR (Toll-like receptor) ligands were assessed. RT-PCR and Western blot analysis were used to determine mRNA and protein level. Pro-inflammatory cytokine mRNA expression levels and phagocytosis were used as functional markers. Data analyzed using t-test, one-way or two-way ANOVA followed by post hoc test. SLAMFs were differentially expressed in THP-1 cells. Differentiation of u-THP-1 to d-THP-1 led to significantly higher SLAMF7 mRNA and protein levels than other SLAMF. In addition, TLR stimuli increased SLAMF7 mRNA expression but not protein expression. Importantly, SLAMF7 agonist antibody and TLR ligands synergistically increased the mRNA expression levels of IL-1β, IL-6 and TNF-α, but had no effect on phagocytosis. SLAMF7 knocked-down in d-THP-1 significantly lowered TLR-induced mRNA expressions of pro-inflammatory markers. SLAM family proteins are differentially regulated by differentiation and TLRs. SLAMF7 enhanced TLR-mediated induction of pro-inflammatory cytokines in monocytes and macrophages but not phagocytosis.
为了进一步阐明信号淋巴细胞激活分子家族（SLAMF）蛋白成员在人单核细胞和巨噬细胞中的表达、调节和功能。未分化的单核细胞 THP-1 细胞（u-THP-1）和分化的 THP-1 巨噬细胞（d-THP-1）被用作该研究的培养模型。评估了细胞对分化剂佛波醇酯（25ng/ml）和 TLR（Toll 样受体）配体的反应。使用 RT-PCR 和 Western blot 分析来确定 mRNA 和蛋白水平。促炎细胞因子 mRNA 表达水平和吞噬作用被用作功能标记。使用 t 检验、单因素或双因素方差分析，然后进行事后检验进行数据分析。SLAMF 在 THP-1 细胞中表达不同。u-THP-1 分化为 d-THP-1 导致 SLAMF7 mRNA 和蛋白水平明显高于其他 SLAMF。此外，TLR 刺激增加了 SLAMF7 mRNA 表达，但不增加蛋白表达。重要的是，SLAMF7 激动剂抗体和 TLR 配体协同增加了 IL-1β、IL-6 和 TNF-α 的 mRNA 表达水平，但对吞噬作用没有影响。d-THP-1 中的 SLAMF7 敲低显著降低了 TLR 诱导的促炎标志物的 mRNA 表达。SLAM 家族蛋白受分化和 TLR 调节。SLAMF7 增强了 TLR 介导的单核细胞和巨噬细胞中促炎细胞因子的诱导，但不增强吞噬作用。
