Division of Periodontics, Department of Stomatology, School of Dentistry, University of São Paulo, São Paulo, São Paulo, Brazil.
Division of Periodontics, Department of Prosthodontics and Periodontics, Piracicaba Dental School, University of Campinas, Piracicaba, São Paulo, Brazil.
J Periodontol. 2019 Jul;90(7):747-755. doi: 10.1002/JPER.18-0220. Epub 2019 Feb 12.
Mesenchymal stem cells differentiate into distinct mesenchymal cell lineages and regulate the immune response. The aim of this study was to determine whether periodontal ligament-derived mesenchymal stem cells (PDLSCs) have the ability to modulate neutrophil responses via paracrine mechanisms.
CD105-enriched PDLSCs were seeded for 24 h and challenged with Porphyromonas gingivalis total protein extract (PgPE) (0 or 2 ug/mL) for 3 h. Cells were then washed and further cultured for 18 h and the supernatants were collected and stored. Next, neutrophil-differentiated human promyelocytic leukemia HL-60 cells (HL60D) were treated with PDLSCs supernatants and HL-60D activation and functional responses were determined.
PgPE treatment induced higher secretion of inflammatory markers and chemokines by PDLSCs, including RANTES, eotaxin, interferon (IFN)-γ- inducible protein 10 (IP-10), monocyte chemoattractant protein-1 (MCP-1), IFN-γ, interleukin (IL)-6, IL-8 and IL-1ra (P < 0.05). HL-60D recruitment rate was increased by 4.7 ± 1.09-fold when exposed to PgPE-treated PDLSCs supernatants. PgPE-treated PDLSCs supernatants promoted a 1.78 ± 1.04-fold increase in the production of intracellular reactive oxygen species (ROS) by PMA-stimulated HL-60D, whereas PgPE-untreated PDLSCs supernatants led to a 16% reduction in intracellular ROS. In sharp contrast, neither PgPE-untreated nor PgPE-treated PDLSCs supernatants altered tumor necrosis factor (TNF)-α and IL-1β secretion by HL-60D cells.
Together, these findings suggest an important role of PDLSCs in the recognition of P. gingivalis, paracrine recruitment and activation of antimicrobial mechanisms in innate immune cells, without interfering in cytokine responses.
间充质干细胞可分化为不同的间充质细胞谱系，并调节免疫反应。本研究旨在确定牙周膜源性间充质干细胞（PDLSCs）是否具有通过旁分泌机制调节中性粒细胞反应的能力。
用 CD105 富集的 PDLSCs 接种 24 小时，用牙龈卟啉单胞菌总蛋白提取物（PgPE）（0 或 2ug/ml）刺激 3 小时。然后洗涤细胞并进一步培养 18 小时，收集上清液并储存。接下来，用 PDLSCs 上清液处理中性粒细胞分化的人早幼粒细胞白血病 HL-60 细胞（HL60D），并测定 HL60D 的激活和功能反应。
PgPE 处理诱导 PDLSCs 更高分泌炎症标志物和趋化因子，包括 RANTES、嗜酸性粒细胞趋化因子、干扰素（IFN）-γ诱导蛋白 10（IP-10）、单核细胞趋化蛋白-1（MCP-1）、IFN-γ、白细胞介素（IL）-6、IL-8 和 IL-1ra（P<0.05）。当暴露于 PgPE 处理的 PDLSCs 上清液时，HL60D 的募集率增加了 4.7±1.09 倍。PgPE 处理的 PDLSCs 上清液促进 PMA 刺激的 HL60D 产生细胞内活性氧物质（ROS）增加 1.78±1.04 倍，而 PgPE 未处理的 PDLSCs 上清液导致细胞内 ROS 减少 16%。相比之下，PgPE 未处理或处理的 PDLSCs 上清液均未改变 HL60D 细胞分泌肿瘤坏死因子（TNF）-α和白细胞介素（IL）-1β。
综上所述，这些发现表明 PDLSCs 在识别牙龈卟啉单胞菌、旁分泌募集和激活固有免疫细胞中的抗菌机制方面发挥重要作用，而不干扰细胞因子反应。
