基质细胞衍生因子1α及其受体CXCR4在人牙髓细胞中的表达

目的 研究体外培养人牙髓细胞(human dental pulp cells,HDPC)上CXCR4的表达情况,检测大肠杆菌脂多糖(lipopolysaccharide,LPS)和肿瘤坏死因子α(TNF-α)刺激后HDPC培养上清液中基质细胞衍生因子1α(stromal cell-derived factor-1α,SDF-1α)的表达水平,探讨人工重组SDF-1α(recombinant human SDF-1α,rhSDF-1α)对HDPC增殖及迁移的影响.方法 采用免疫细胞化学及间接免疫荧光技术检测HDPC上CXCR4的表达.用不同浓度LPS(0.1、1、10、100 mg/L)和TNF-α(1、10、100μg/L)刺激HDPC 48 h后,ELISA法检测HDPC培养上清液中SDF-1α含量的变化.同时甲基噻唑基四唑(MTT)法及体外趋化实验观察不同浓度rhSDF-1α对HDPC增殖及迁移的影响.结果 正常HDPC胞膜表达CXCR4且其培养上清液分泌SDF-1α,浓度约为(4513.55±962.92)ng/L.在用LPS和TNF-α刺激HDPC后,SDF-1α的表达水平均显著降低(P＜0.05).50、100和200μg/L的rhSDF-1α可促进HDPC的增殖(P＜0.05),50和100μg/L rhSDF-1α作用9 h可显著趋化HDPC的迁移(P＜0.01).结论 CXCR4在HDPC上表达且SDF-1α能促进HDPC的增殖及迁移;SDF-1-CXCR4轴可能在牙髓组织损伤修复中发挥重要作用.     

脂多糖刺激人牙髓干细胞分泌的外泌体联合基质细胞衍生因子-1对牙髓再生的影响

目的探讨轻度炎症状态下人牙髓干细胞(human dental pulp stem cell,hDPSC)产生的外泌体与基质细胞衍生因子-1(stromal cell-derived factor-1,SDF-1)联合应用对牙髓组织再生的影响。方法分离培养hDPSC,脂多糖(lipopolysaccharide,LPS)刺激hDPSC,超速离心法提取hDPSC经LPS刺激后产生的外泌体(exosomes from lipopolysaccharide-stimulated hDPSC,L-EXO)和正常状态下分泌的外泌体(exosome from normal hDPSC,N-EXO),通过透射电镜和蛋白质印迹法鉴定提取物。将40只6~8周龄的SD大鼠通过随机数字表法分为S组(单独应用SDF-1)、L+S组(SDF-1与L-EXO联合应用)、N+S组(SDF-1与N-EXO联合应用)和空白对照组(根管内不植入任何物质),每组10只。以双侧下颌第一磨牙为实验牙,建立大鼠无髓根管模型,根据分组分别在根管内植入不同的内容物。植入后30 d过量麻醉处死所有大鼠,取大鼠双侧下颌骨组织,应用HE、Masson及免疫组织化学染色法进行组织学评价。结果HE染色结果显示,除空白对照组外,其他3组根管内均可见新生牙髓样组织,其中L+S组根管内新生组织的量及组织中的细胞数量最多,S组最少。Masson染色结果显示,L+S组矿化组织沿根管壁纵向排列,胶原纤维有序排列,N+S组呈无规律紊乱分布。定量分析各组新生血管面积,结果显示L+S组血管密度[(2.03±0.65)%]显著高于S组[(0.65±0.05)%]及N+S组[(1.06±0.38)%](F=5.879,P<0.05)。免疫组织化学结果显示,S组及L+S组的趋化因子受体4表达量显著低于N+S组(F=8.633,P<0.01)。结论hDPSC分泌的外泌体联合SDF-1可提高根管内新生组织的量和组织中的血管密度,L-EXO的作用较N-EXO强,并且新生组织中胶原纤维及矿化组织的排列更规律有序。     

基质细胞衍生因子1在人炎症牙髓组织中表达的实验研究

目的:研究基质细胞衍生因子1(Stromal cell-derived factor-1,SDF-1)及其受体CXCR4在人炎性牙髓组织中的表达,探讨SDF-1/CXCR4轴在牙髓炎症发生发展中的可能作用。方法:采用免疫组织化学染色的方法检测SDF-1和CXCR4阳性细胞在健康、炎症牙髓组织中的分布情况。以实时荧光定量RT-PCR方法检测SDF-1mRNA在健康和炎症牙髓中的表达。结果:炎性牙髓中SDF-1、CXCR4主要分布于炎性细胞、成牙本质细胞和微血管内皮细胞。而正常组牙髓少见SDF-1、CXCR4阳性细胞。炎性牙髓中SDF-1mRNA的表达较健康牙髓显著增强。结论:与正常牙髓相比,炎性牙髓组织中SDF-1、CXCR4阳性细胞明显增多。炎性牙髓中SDF-1表达水平明显上调。SDF-1/CXCR4轴可能参与了牙髓炎症损伤和修复过程。     

基质细胞衍生因子-1及其受体CXCR4在成体干细胞迁移中的作用

基质细胞衍生因子-1是一种重要的造血与非造血系干细胞形态发生因子和趋化因子。基质细胞衍生因子-1与其受体CXCR4结合,所介导的成体干细胞迁移归巢在多种组织器官损伤后的再生修复中发挥重要作用。基质细胞衍生因子-1及其受体CXCR4组成的功能轴在成体干细胞尤其是骨髓源干细胞迁移方面的研究进展,为研究牙髓干细胞迁移提供了新的方向。     

Expression of insulin-like growth factor-1 receptor in human pulp tissue

Insulin-like growth factor-1 (IGF-1) plays an important role in cell proliferation and differentiation. The purpose of this study was to use a radioreceptor assay to evaluate whether IGF-1 receptors are present in human pulp and to determine whether differences in its expression are found in the pulp tissue of teeth having incomplete or complete root development. Twenty pulps were obtained from freshly extracted human third molars; they were then processed and labeled with I-IGF-1. The results showed IGF-1 receptor expression in all human pulp samples. t test revealed statistically significant higher expression in the pulps from teeth having incomplete root development (P <0.005). Given the functions of this growth factor system in other tissues, the present findings are consistent with the hypothesis that IGF-1 contributes toward forming and mineralizing dental tissues as well as in pulp-repairing processes.     

BMP4-regulated human dental pulp stromal cells promote pulp-like tissue regeneration in a decellularized dental pulp matrix scaffold

Odontology - Pulp regeneration with stem cells is a promising alternative for treating periapical and pulp diseases of young permanent teeth. The aim of this study was to characterize...     

Expression of toll-like receptor 2 and 4 in dental pulp

Toll-like receptors (TLRs) are important factors in innate immune responses because they mediate signals from bacterial cell wall components during inflammatory reactions. However, the role of TLR in dental pulp, which is bounded by hard tissues, is little understood. The present study investigated the expression of TLR-2 and TLR-4 in experimentally inflamed pulp by quantitative real-time polymerase chain reaction and immunohistochemistry. Total RNA isolated from pulp tissue from 0 to 72 hours after bacterial dentinal infection. The TLR-2 messenger RNA (mRNA) level was 30-fold higher than the TLR-4 mRNA level at 9 hours. The TLR-2 mRNA level in pulp began to increase by 3 hours after bacterial infection, reaching a maximum level after 9 hours and gradually decreasing from 9 to 72 hours. Numerous TLR-2- and CD64-positive cells detected on macrophage and dendritic-like cells, TLR-4-positive cells detected a little in the pulp at 9 hours. These results suggest that TLR-2 may be mainly regulated during the early stage of pulp inflammation triggered by bacterial infection.     

正常及炎症状态人牙髓中八聚体结合转录因子4B的表达

目的 研究人正常及炎症牙髓组织中八聚体结合转录因子4B(Oct-4B)的表达特点,检测大肠杆菌脂多糖刺激后人牙髓细胞( HDPCs)中Oct-4B的表达水平,以探讨Oct-4B在牙髓炎症中的可能作用.方法 采用免疫组织化学和反转录聚合酶链反应( RT-PCR)方法检测正常及炎症牙髓组织中Oct-4B的表达情况.RT-PCR检测1 mg/L脂多糖刺激HDPC 24、48、72 h后Oct-4B和热休克蛋白70(HSP70)表达水平的变化.结果 正常牙髓组织中未检测到Oct-4B的表达,炎症牙髓组织病灶处牙髓成纤维细胞和炎症细胞胞质中Oct-4B表达强阳性.炎症牙髓组织中Oct-4B mRNA水平显著高于正常牙髓组织(P<0.05).脂多糖刺激48.72 h后,HDPC中Oct-4B和HSP70 mRNA水平同步上调(P<0.05).结论 Oct-4B在炎症牙髓组织中高表达,且脂多糖刺激可上调牙髓细胞内Oct-4B表达,Oct-4B可能参与牙髓炎症修复过程.     

Expression and characterization of vanilloid receptor subtype 1 in human dental pulp cell cultures

The expression of the vanilloid receptor subtype 1 (VR1, TRPV1) was detected in human dental pulp fibroblasts (PF-10) using RT-PCR, Western blotting, and immunocytochemical analysis. As revealed by ELISA, capsaicin induced IL-6 expression in PF-10 cells, and the VR1 antagonist capsazepine dose-dependently inhibited capsaicin-induced IL-6 production, indicating that capsaicin-induced IL-6 expression is related to VR1 activation. The interaction between capsaicin and mitogen-activated protein kinases (MAPKs) was investigated. The phosphorylation of p38 MAPK and c-Jun NH2-terminal kinase (JNK) were detected after capsaicin stimulation. p38 MAPK is involved in capsaicin-induced IL-6 production, as shown by the use of specific inhibitors of this kinase. The result of EMSA showed that capsaicin inhibited tumor necrosis factor-alpha (TNF-alpha)-induced nuclear factor-kappa B (NF-kappaB) activation in PF-10 cell cultures. These results suggest that the activation of VR1 plays an important role in dental pulp inflammation.     

Leptin受体在人牙髓干细胞中表达的实验研究

目的:研究体外培养人牙髓干细胞表型特征及生物学性状,检测Leptin受体在牙髓干细胞表面的表达.方法:采用组织块法和酶消化法分离培养人牙髓十细胞;免疫组化法、免疫荧光法检测细胞表面分子的表达;体外诱导分化实验检测细胞多向分化能力.免疫组化法检测Leptin受体在人牙髓干细胞表面的表达.结果:分离获得的牙髓干细胞波形丝蛋白和CD146表达阳性,具有向脂肪细胞和成骨细胞分化的潜能;Leptin受体在牙髓干细胞表面阳性表达.结论:分离培养的牙髓干细胞具有干细胞的表型特征及生物学性状,Leptin受体可表达于牙髓干细胞.     

人牙龈干细胞的分离鉴定及基质细胞衍生因子-1对其趋化效应的研究

目的 研究基质细胞衍生因子-1（SDF-1）受体CXCR4在人牙龈干细胞（GMSCs）上的表达及SDF-1对人GMSCs的趋化效应。方法 通过有限稀释法分离并培养人GMSCs,检测其表面干细胞标志物的表达情况,测试其克隆形成率及多向分化能力,利用免疫荧光染色法检测人GMSCs上SDF-1受体CXCR4的表达,用Transwell细胞培养室检测不同质量浓度SDF-1对人GMSCs的趋化反应,光镜下计数迁移至滤膜下侧面的不同视野的细胞数。结果 人GMSCs具有较高的自我更新能力,在体外呈克隆状生长,表达间充质干细胞表面标志物CD44、CD73、CD90、CD105和CD166,而造血干细胞表面标志物CD14、CD34和CD45的表达为阴性。体外诱导培养的人GMSCs能够向成骨细胞及成脂细胞分化,其克隆形成率为21.4%±2.8%。免疫荧光染色显示,人GMSCs表达SDF-1受体CXCR4。SDF-1的质量浓度为100、200 ng·mL^-1时,Transwell细胞培养室中迁移的细胞数目（每高倍视野分别为189.3±4.4和164.6±4.9）显著多于空白对照组（每高倍视野47.8±2.5）（P<0.01）;使用CXCR4中和抗体处理后,人GMSCs的迁移效应明显受到抑制（每高倍视野降低为29.0±2.4,P<0.01）。结论 人GMSCs表达趋化因子SDF-1受体CXCR4,SDF-1对人GMSCs有趋化效应,这种趋化效应可能是通过其特异性受体CXCR4介导的。     

转录因子Klf4在人牙髓组织和牙髓成纤维细胞中的表达研究

目的研究转录因子Klf4在人牙髓组织和体外培养的牙髓成纤维细胞中的表达特点。方法采用免疫荧光技术检测Klf4和增殖标记物ki67在人牙髓组织及体外培养的牙髓成纤维细胞中的表达情况;利用逆转录聚合酶链反应(RT-PCR)检测Klf4在人牙髓细胞和矿化诱导14 d的表达情况。结果人牙髓中,Klf4主要表达在成牙本质样细胞和血管内皮细胞中;在体外培养的牙髓成纤维细胞中,与诱导前相比,Klf4在矿化诱导14 d时的表达明显增强。结论 Klf4在成牙本质细胞中呈特异性表达,可能与成牙本质细胞分化相关。