Department of Clinical Neuroscience, Karolinska Institutet, Center for Molecular Medicine, Karolinska Hospital at Solna, Stockholm, Sweden
Department of Clinical Neuroscience, Karolinska Institutet, Center for Molecular Medicine, Karolinska Hospital at Solna, Stockholm, Sweden.
J Leukoc Biol. 2016 Mar;99(3):437-46. doi: 10.1189/jlb.1AB0914-433RR. Epub 2015 Oct 29.
Dendritic cells are professional APCs that play a central role in the initiation of immune responses. The limited ex vivo availability of dendritic cells inspires the widespread use of bone marrow-derived dendritic cells as an alternative in research. However, the functional characteristics of bone marrow-derived dendritic cells are incompletely understood. Therefore, we compared functional and phenotypic characteristics of rat bone marrow-derived dendritic cells generated with GM-CSF/IL-4 or FLT3 ligand bone marrow-derived dendritic cells. A comparison of surface markers revealed that FLT3 ligand-bone marrow-derived dendritic cells expressed signal regulatory protein α, CD103, and CD4 and baseline levels of MHC class II, CD40, and CD86, which were highly up-regulated upon stimulation. Conversely, GM-CSF/IL-4-bone marrow-derived dendritic cells constitutively expressed signal regulatory protein α, CD11c, and CD11b but only mildly up-regulated MHC class II, CD40, or CD86 following stimulation. Expression of dendritic cell-associated core transcripts was restricted to FLT3 ligand-bone marrow-derived dendritic cells . GM-CSF/IL-4-bone marrow-derived dendritic cells were superior at phagocytosis but were outperformed by FLT3 ligand-bone marrow-derived dendritic cells at antigen presentation and T cell stimulation in vitro. Stimulated GM-CSF/IL-4-bone marrow-derived dendritic cells secreted more TNF, CCL5, CCL20, and NO, whereas FLT3 ligand-bone marrow-derived dendritic cells secreted more IL-6 and IL-12. Finally, whereas GM-CSF/IL-4-bone marrow-derived dendritic cell culture supernatants added to resting T cell cultures promoted forkhead box p3(+) regulatory T cell populations, FLT3 ligand-bone marrow-derived dendritic cell culture supernatants drove Th17 differentiation. We conclude that rat GM-CSF/IL-4-bone marrow-derived dendritic cells and FLT3 ligand-bone marrow-derived dendritic cells are functionally distinct. Our data support the current rationale that FLT3 ligand-bone marrow-derived dendritic cells mostly resemble classic dendritic cells but comprise additional minor subpopulations, whereas GM-CSF/IL-4-bone marrow-derived dendritic cells resemble monocyte-derived inflammatory dendritic cells (iNOS-positive monocyte-derived cells).
树突状细胞是专业的 APCs，在免疫反应的启动中发挥核心作用。骨髓来源的树突状细胞在体外的可用性有限，这激发了人们广泛使用它作为研究中的替代物。然而，骨髓来源的树突状细胞的功能特征还不完全清楚。因此，我们比较了用 GM-CSF/IL-4 或 FLT3 配体生成的大鼠骨髓来源的树突状细胞的功能和表型特征。表面标志物的比较表明，FLT3 配体-骨髓来源的树突状细胞表达信号调节蛋白 α、CD103 和 CD4，以及 MHC Ⅱ类、CD40 和 CD86 的基线水平，这些在刺激后高度上调。相反，GM-CSF/IL-4-骨髓来源的树突状细胞组成性表达信号调节蛋白 α、CD11c 和 CD11b，但在刺激后仅轻度上调 MHC Ⅱ类、CD40 或 CD86。树突状细胞相关核心转录物的表达仅限于 FLT3 配体-骨髓来源的树突状细胞。GM-CSF/IL-4-骨髓来源的树突状细胞在吞噬作用方面表现优异，但在体外抗原呈递和 T 细胞刺激方面逊于 FLT3 配体-骨髓来源的树突状细胞。刺激后的 GM-CSF/IL-4-骨髓来源的树突状细胞分泌更多的 TNF、CCL5、CCL20 和 NO，而 FLT3 配体-骨髓来源的树突状细胞分泌更多的 IL-6 和 IL-12。最后，GM-CSF/IL-4-骨髓来源的树突状细胞培养上清液加入静止 T 细胞培养物中可促进叉头框 P3(+)调节性 T 细胞群体，而 FLT3 配体-骨髓来源的树突状细胞培养上清液则驱动 Th17 分化。我们得出结论，大鼠 GM-CSF/IL-4-骨髓来源的树突状细胞和 FLT3 配体-骨髓来源的树突状细胞在功能上是不同的。我们的数据支持当前的观点，即 FLT3 配体-骨髓来源的树突状细胞更类似于经典的树突状细胞，但包含额外的亚群，而 GM-CSF/IL-4-骨髓来源的树突状细胞类似于单核细胞衍生的炎症性树突状细胞（iNOS 阳性单核细胞衍生细胞）。
