Nordic Institute of Dental Materials, Sognsveien 70A, N-0855 Oslo, Norway; Norwegian Institute of Public Health, Domain of Infection Control and Environmental Health, P.O. Box 4404, N-0403 Oslo, Norway.
Nordic Institute of Dental Materials, Sognsveien 70A, N-0855 Oslo, Norway.
Dent Mater. 2019 Oct;35(10):e235-e248. doi: 10.1016/j.dental.2019.07.005. Epub 2019 Aug 1.
Leakage of unpolymerized methacrylate monomers after placement of methacrylate-containing polymeric dental materials leads to human exposure. Based on studies using murine macrophages and LPS from Escherichia coli (E. coli), dental monomers like 2-hydroxyethyl methacrylate (HEMA) are known to inhibit lipopolysaccharide (LPS) induced cytokine release. The aim of this study was to establish a model system with relevance for human oral monomer exposure using exposure to live gram-positive bacteria, and to confirm the HEMA-induced effects on cytokine release in this model.
The human THP-1 monocyte cell line was differentiated to macrophages using phorbol 12-myristate 13-acetate (PMA), before exposure to 0.5-2mM HEMA and live Staphylococcus aureus (S. aureus) in various multiplicity of infections (MOI). Cytokine release and cytotoxicity were determined after (i) 2-24h pre-exposure to HEMA followed by 2-4h S. aureus exposure and (ii) 2-4h simultaneous exposure. The 24h pre-exposure regime was also tested in primary human airway macrophages and for phagocytosis of S. aureus in THP-1 macrophages.
HEMA attenuated the cytokine release more strongly in the pre-exposure than combined exposure regime, with a maximal reduction of 95% in the S. aureus-induced cytokine release. A MOI of 0.1 (corresponding to a bacteria-macrophage ratio of 1:10) was determined to be optimal in the THP-1 macrophages as it induced sufficient cytokine release and negligible cytotoxicity. Attenuated release of S. aureus-induced interleukin (IL)-1β after HEMA exposure was confirmed in primary airway macrophages, while HEMA increased the phagocytosis of S. aureus in THP-1 cells.
The model was successfully established and attenuated bacteria-induced cytokine release after HEMA exposure confirmed.
放置含甲基丙烯酸盐的聚合牙科材料后未聚合的甲基丙烯酸盐单体的泄漏会导致人体暴露。基于使用鼠巨噬细胞和大肠杆菌（E. coli）来源的脂多糖（LPS）进行的研究，已知牙科单体如 2-羟乙基甲基丙烯酸酯（HEMA）可抑制脂多糖（LPS）诱导的细胞因子释放。本研究的目的是使用活革兰氏阳性菌建立与人口腔单体暴露相关的模型系统，并确认 HEMA 在该模型中对细胞因子释放的诱导作用。
使用佛波醇 12-肉豆蔻酸 13-乙酸酯（PMA）将人 THP-1 单核细胞系分化为巨噬细胞，然后在不同的感染复数（MOI）下将 0.5-2mM HEMA 和活金黄色葡萄球菌（S. aureus）暴露于细胞中。在（i）HEMA 预暴露 2-24 小时后再暴露 2-4 小时金黄色葡萄球菌和（ii）同时暴露 2-4 小时后，测定细胞因子释放和细胞毒性。还在原代人气道巨噬细胞中测试了 24 小时预暴露方案，并在 THP-1 巨噬细胞中测试了金黄色葡萄球菌的吞噬作用。
HEMA 在预暴露时比联合暴露时更能强烈减弱细胞因子的释放，金黄色葡萄球菌诱导的细胞因子释放最大减少 95%。MOI 为 0.1（相当于细菌-巨噬细胞比为 1:10）被确定为 THP-1 巨噬细胞中的最佳值，因为它诱导了足够的细胞因子释放和可忽略不计的细胞毒性。在原代气道巨噬细胞中，HEMA 暴露后金黄色葡萄球菌诱导的白细胞介素（IL）-1β释放减弱得到证实，而 HEMA 增加了 THP-1 细胞中金黄色葡萄球菌的吞噬作用。
成功建立了该模型，并证实了 HEMA 暴露后减弱了细菌诱导的细胞因子释放。
