摘要：

目的：初步探讨炎性牙周膜干细胞（periodontal ligament stem cells, PDLSCs）在牙周炎中对T细胞免疫的影响及可能机制。方法：使用磷酸盐缓冲液（phosphate buffered saline, PBS）和脂多糖（lipopolysaccharide, LPS）刺激PDLSCs模拟健康及炎性环境下的PDLSCs，收集2组PDLSCs条件培养液（conditioned medium, CM），即健康PDLSCs条件培养液（CON-CM组）和炎性PDLSCs条件培养液（LPS-CM组），并收集同批次培养液为阴性对照（NC组），分别将其作用于人正常T淋巴细胞系H9细胞，观察不同CM对T细胞增殖和迁移能力的作用。进一步采用植物血凝素-L（phytohemagglutinin-L, PHA-L）刺激T细胞免疫活化，采用CM作用于活化状态下的H9细胞，并检测T细胞免疫活化相关基因白细胞介素-2（interleukin-2, IL-2）、γ干扰素（interferon-γ, IFN-γ）、白细胞介素-17（interleukin-17, IL-17）、CC趋化因子受体6（CC chemokine receptor 6, CCR6）表达的变化，同时观察LPS刺激对PDLSCs分泌CC趋化因子配体20（CC chemokine ligand 20，CCL20）的影响。结果：与NC组和CON-CM组相比，LPS-CM组能促进T细胞的增殖、迁移，及IL-2、IFN-γ、IL-17和CCR6 的表达（P<0.05），且在LPS的刺激下，PDLSCs分泌的CCL20含量明显增多（P<0.001）。结论：正常PDLSCs具有一定免疫调节作用，而炎性PDLSCs可能通过CCL20-CCR6轴促进了T细胞的增殖、迁移和活化等免疫生物学行为。

关键词: 牙周炎, 牙周膜干细胞, T细胞免疫, CC趋化因子配体20, CC趋化因子受体6

Abstract:

Objective: To explore the inflammatory periodontal ligament stem cells (PDLSCs) on T cell immunity in periodontitis conditions and its possible mechanism. Methods: PDLSCs were stimulated with phosphate buffered saline （PBS) and lipopolysaccharide (LPS) to mimic PDLSCs in healthy and inflammatory environments, and then the two groups of conditioned medium (CM) were collected, namely healthy PDLSCs CM (CON-CM group) and inflammatory PDLSCs CM (LPS-CM group). The same batch of culture medium was collected as the negative control (NC group) as well. They were used to act on human normal T lymphocyte line H9 cells respectively to observe the effects of different CM on T cell proliferation and migration. Furthermore, phytohemagglutinin-L (PHA-L) was used to stimulate T cell immune activation, and CM was used to treat H9 cells in the activated state, then the expression of T cell immune activation related genes—interleukin-2 (IL-2), interferon-γ (IFN-γ), interleukin-17 (IL-17) and CC chemokine receptor 6 (CCR6) were detected, and the effect of LPS stimulation on the secretion of CC chemokine ligand 20 (CCL20) by PDLSCs was observed. Results: Compared with the NC group and the CON-CM group, the LPS-CM group could promote the proliferation and migration of T cells, as well as the expression of IL-2, IFN-γ, IL-17 and CCR6 mRNA (P<0.05). While the content of CCL20 secreted by PDLSCs was significantly increased under LPS stimulation (P<0.001). Conclusion: This study provides evidence that normal PDLSCs have certain immunomodulatory effects, while inflammatory PDLSCs may promote T cell proliferation, migration, activation and other immunobiological behaviors through the CCL20-CCR6 axis.

Key words: periodontitis, periodontal ligament stem cells, T cell immunity, CC chemokine ligand 20, CC chemokine receptor 6

中图分类号: 

• R782