Institute of Pharmacology of Natural Products and Clinical Pharmacology, Ulm University, Ulm, Germany.
Department of Pharmacology, Faculty of Medicine, University of Tripoli, Tripoli, Libya.
J Leukoc Biol. 2022 Oct;112(4):659-668. doi: 10.1002/JLB.1A1221-680R. Epub 2022 Mar 31.
In vitro analysis of human macrophages is generally hampered by the necessity to differentiate them from peripheral blood monocytes. We have analyzed to which extent noncancerous SC monocytes could be used as an in vitro macrophage model. Macrophages differentiated from peripheral monocytes using standard CSF1 and CSF2 protocols for M2 and M1 precursors, respectively, were compared with THP-1-derived macrophages treated with PMA and with SC-derived macrophages differentiated either by CSF1, CSF2, or PMA according to different protocols. The optimal condition for generation of SC macrophages was treatment with PMA for 3 days, followed by 5-days culture without PMA and 24-h polarization with LPS/IFN-γ or IL-4/IL-13. Similar to THP-1, SC cells do not express the monocyte marker CD14 and differentiation to macrophages results neither in CD68 nor in CD14 expression, both of which were expressed by monocyte-derived macrophages. Similar to THP-1-macrophages, a proportion of SC macrophages can be polarized to the M1-like subtype that is characterized by higher expression of CD38, CD86, CD80, TNF-α, and IL-1ra, whereas treatment with IL4/IL13 did not lead to expression of the M2-associated receptors CD163, CD206, and only slightly increased the CD200R expression. Still, SC-M1 express much lower levels of the M1-associated markers compared with monocyte-derived M1 and no IL-1β. The data demonstrate that SC-derived macrophages differ from monocyte-derived macrophages in respect of their morphology, expression of important macrophage markers, phagocytosis. Yet, polarized SC-M1-like cells may with restrictions serve as a model for M1 macrophages, though this model does not provide significant advantages over already well-described THP-1-M1-like cells.
体外分析人巨噬细胞通常受到必须将其从外周血单核细胞中分化出来的限制。我们分析了非癌性 SC 单核细胞在多大程度上可以用作体外巨噬细胞模型。使用 CSF1 和 CSF2 分别针对 M2 和 M1 前体的标准方案从外周血单核细胞中分化而来的巨噬细胞，与用 PMA 处理的 THP-1 衍生的巨噬细胞以及根据不同方案用 CSF1、CSF2 或 PMA 分化的 SC 衍生的巨噬细胞进行了比较。生成 SC 巨噬细胞的最佳条件是用 PMA 处理 3 天，然后在没有 PMA 的情况下培养 5 天，并用 LPS/IFN-γ 或 IL-4/IL-13 极化 24 小时。与 THP-1 相似，SC 细胞不表达单核细胞标志物 CD14，分化为巨噬细胞既不会表达 CD68，也不会表达 CD14，单核细胞衍生的巨噬细胞表达这两种标志物。与 THP-1 巨噬细胞相似，一部分 SC 巨噬细胞可以极化到 M1 样亚型，其特征是 CD38、CD86、CD80、TNF-α 和 IL-1ra 的表达更高，而用 IL4/IL13 处理不会导致 M2 相关受体 CD163、CD206 的表达，仅略微增加 CD200R 的表达。尽管如此，与单核细胞衍生的 M1 相比，SC-M1 表达的 M1 相关标志物水平要低得多，且没有 IL-1β。这些数据表明，SC 衍生的巨噬细胞在形态、重要巨噬细胞标志物的表达、吞噬作用等方面与单核细胞衍生的巨噬细胞不同。然而，极化的 SC-M1 样细胞可能会受到限制，可以作为 M1 巨噬细胞的模型，但与已经描述清楚的 THP-1-M1 样细胞相比，这种模型并没有提供明显的优势。
