根尖周炎动物模型中CD14、TLR4的表达

目的研究大鼠根尖周炎炎症组织中脂多糖炎症信号受体CD14、Toll样受体4（Toll．1ikereceptor4，TLR4）的表达特点，探讨根尖周炎中脂多糖的信号转导途径。方法建立大鼠磨牙内毒素根尖周炎模型，采用免疫组化染色观察根尖周炎炎症组织中CD14、TLR4的表达情况，并计算CD14、TLR4的阳性细胞率。结果正常根尖周组织中未发现CD14和TLR4免疫阳性细胞，根尖周炎症组织中CD14和TLR4表达阳性，CD14、TLR4阳性细胞率差异无统计学意义（P〉0．05）。结论与正常根尖周组织相比，炎症根尖周组织中CD14和TLR4的表达显著增强，CD14和TLR4的表达量差异无统计学意义，提示脂多糖可能通过CD14、TLR4信号受体在根尖周炎症中发挥作用。     

脂多糖信号受体CD14、TLR4在人牙髓组织和牙髓成纤维细胞中的表达

目的研究人牙髓组织和牙髓成纤维细胞中脂多糖（LPS）信号受体CD14、TLR4的表达特点,探讨牙髓炎症组织中LPS的信号转导途径.方法采用免疫组化染色法观察健康和炎症牙髓组织中CD14、TLR4的表达情况;应用直接免疫荧光标记法,采用流式细胞术检测体外培养人牙髓成纤维细胞在LPS刺激前后的CD14、TLR4阳性细胞率和细胞表面平均荧光强度.结果正常牙髓组织中未见CD14、TLR4阳性细胞;炎症牙髓组织中可见大量CD14、TLR4阳性细胞,CD14、TLR4阳性细胞率差异无统计学意义（P＞0.05）.牙髓成纤维细胞经LPS刺激后,TLR4平均荧光表达强度和TLR4阳性细胞率均显著增高（P＜0.05）,而CD14在LPS刺激前、后均无表达.结论炎症牙髓组织中CD14、TLR4的阳性表达,提示LPS可能通过CD14、TLR4信号受体在牙髓炎症组织中发挥作用,而牙髓成纤维细胞在LPS刺激后仅表达TLR4,表明LPS可能通过TLR4对牙髓成纤维细胞发挥作用.     

CD14、TLR4在大鼠尖周炎症组织中的表达

目的:探讨CD14、TLR4在尖周组织中的分布和表达,为阐明CD14、TLR4在LPS引起的炎症反应中的作用机制提供实验依据.方法:分别将Pe、Pg菌液封入大鼠髓腔建立大鼠尖周炎症模型,并以髓腔自然开放和开髓后无菌坏死作为对照.免疫组织化学染色观察CD14、TLR4在尖周组织的分布情况.结果:4组的尖周炎症组织中均可见大量CD14、TLR4表达阳性细胞,以单核巨噬细胞为主.结论:LPS信号受体CD14和TLR4 可能参与大鼠LPS介导的尖周炎症反应.     

Toll样受体4在大鼠实验性牙髓炎和根尖周炎中的表达

目的:建立大鼠实验性牙髓炎及根尖周炎模型,了解TLR4在大鼠牙髓和根尖周组织的表达情况。方法:采用单纯髓腔开放法建立大鼠实验性牙髓炎及根尖周炎模型,进行组织学及X线片观察。免疫组化检测TLR4在牙髓炎中的表达,RT-PCR检测TLR4在根尖周炎中的表达。结果:组织学及X线观察证实成功复制大鼠牙髓炎及根尖周炎模型,免疫组化结果表明大鼠正常牙髓组织成牙本质细胞层TLR4阳性表达,牙髓内部血管内皮细胞亦见表达,牙髓成纤维细胞未见表达。炎症牙髓组织TLR4表达较正常组增强。RT-PCR检测发现正常和炎症根尖周组织均有TLR4mRNA表达,炎症组表达较正常组增强。结论:TLR4在牙髓组织和根尖周组织均有表达并参与了牙髓根尖周炎症的发生和发展。     

CD14、TLR4在人炎症牙髓组织中的表达

目的 探讨CD14、TLR4在人牙髓组织中的表达,为阐明CD14、TLB4在LPS引起的炎症反应中的作用机制提供实验依据.方法 通过免疫组织化学染色和流式细胞术观察正常、深龋和牙髓炎牙髓组织中CD14、TLB4表达情况.结果 免疫组化染色观察正常组牙髓组织中未见CD14、TLR4阳性表达细胞;深龋组中可见CD14、TLB4表达阳性细胞,多为中性粒细胞阳性染色;慢性牙髓炎组可见大量CD14、TLR4表达阳性细胞,多为单核细胞、淋巴细胞阳性染色.流式细胞术检测到CD14、TLB4阳性细胞率随牙髓组织炎症的加重而增大;深龋组和牙髓炎组中TLB4的平均荧光强度比CD14高.结论 在牙髓炎症发展过程中,CD14、TLB4阳性细胞表达率随牙髓组织炎症的加重而增大,与炎症程度呈正相关.同时检测到在深龋组和牙髓炎组中TLR4的平均荧光强度比CD14高,可以推测LPS主要通过TLR4进行信号转导.     

人正常及炎症牙髓中炎症信号受体TLR4表达的研究

目的:研究人正常及炎症牙髓组织中炎症信号受体TLR4的表达特点,探讨其在牙髓和根尖周组织炎症中的可能作用。方法:采用激光共聚焦扫描显微镜和免疫荧光技术,检测正常及炎症牙髓TLR4的表达情况。结果:正常牙髓组织中未发现TLR4免疫阳性细胞,炎症牙髓组织病灶处TLR4表达强阳性。正常组平均荧光强度为28.80±2.57,炎症组为258.12±24.51(P<0.001)。结论:与正常牙髓组织相比,炎症牙髓组织TLR4表达显著增强,提示其可能参与牙髓组织炎症过程。     

干细胞因子在人慢性根尖周炎组织中表达的研究

目的:观察干细胞因子(stem cell factor, SCF)在人慢性根尖周炎病变组织中成纤维细胞(fibroblasts, FBs)、内皮细胞(endothelial cells, ECs)及巨噬细胞(macrophages, m )上的表达,探讨SCF阳性的FBs、ECs及m 在人慢性根尖周炎发病机制中的作用。方法:本实验共收集50例根尖周组织标本,其中根尖周肉芽肿组15例,根尖周囊肿组15例,正常对照组20例。组织标本经福尔马林液固定,石蜡包埋、制作连续切片。HE染色,光学显微镜下观察各组标本的组织学变化;经免疫荧光双染色(double immunofluorescence, DIF),在荧光显微镜下观察SCF在根尖周组织FBs、ECs及m 上表达的情况。结果:DIF结果显示,两组慢性根尖周炎组织中的CD334-SCF双阳性FBs、CD31-SCF双阳性ECs及CD14-SCF双阳性m 密度较正常对照组显著增多(P＜0.01);根尖周囊肿组与根尖周肉芽肿组的CD334-SCF双阳性FBs及CD31-SCF双阳性ECs密度无显著性差异;根尖周肉芽肿组CD14-SCF双阳性m 密度明显高于根尖周囊肿组(P＜0.01)。结论:结果提示CD334-SCF双阳性FBs、CD31-SCF双阳性ECs及CD14-SCF双阳性m 与慢性根尖周炎的发生、发展及致病机制有关。     

窝洞内内毒素对牙髓组织LPS结合受体TLR4表达的影响研究

目的 动物实验观察窝洞内内毒素对牙髓组织LPS结合受体TLR4表达的影响,探讨牙髓组织在LPS刺激后的信号转导途径.方法 在8头小型猪磨牙和前磨牙上制备不同深度窝洞,窝洞分为牙釉质深层组、牙本质浅层组、牙本质深层组.封入一定量的内毒素,分另q于术后3天、7天、14天、28天处死动物取牙.采用免疫组织化学染色的方法,观察小型猪磨牙和前磨牙窝洞内封入内毒素后牙髓组织中TLR4的表达和分布.结果 小型猪正常牙髓中未见TLR4阳性细胞.内毒素实验组随着窝洞深度增加,TLR4阳性细胞数增加.在深窝洞组3a窝洞下方牙髓组织中TLR4阳性细胞多为中性粒细胞表达,其他实验组多为单核细胞表达.结论 牙髓组织中TLR4的表达提示内毒素通过牙本质渗透至牙髓,通过LPS信号受体TLR4在牙髓组织的炎症发展过程中发挥作用.     

IL-17在乳牙根尖周病损组织中的表达

目的:检测IL-17在乳牙根尖周病损组织中的表达和分布,分析其在不同病理类型及炎症程度之间的关系,探讨其在乳牙慢性根尖周炎发病机制中的可能作用。方法:收集120例乳牙慢性根尖周病损组织行常规组织病理学检查,确定病理类型并按炎症细胞浸润程度分级;免疫组织化学法检测组织中IL-17的分布特点;ELISA法检测IL-17的蛋白表达量。结果:120例乳牙慢性根尖周病损组织中根尖周肉芽肿占65.8%,根尖周囊肿占18.4%,根尖周脓肿占15.8%。IL-17在3种病理类型中均有表达,主要表达于淋巴细胞、浆细胞。ELISA结果显示IL-17在不同病理类型组中的表达均低于正常对照组,在根尖肉芽肿组中的表达与炎症程度呈负相关。结论:IL-17在乳牙根尖周病损组织内广泛存在,随炎症程度加重表达逐渐降低,推测IL-17在乳牙慢性根尖周炎的病程进展中可能发挥一定的抑制作用。     

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目的 通过免疫组化法检测正常和实验性根尖周炎进展过程中根尖周组织整合素β1表达的分布情况及规律,探讨其在根尖周组织炎症进展中的作用。方法 取磨牙牙髓暴露不同时间(0、7、14、21、28 d)的大鼠上颌骨行整合素β1免疫组化染色,观察根尖周组织中整合素β1表达部位与表达程度。结果 整合素β1广泛表达于正常大鼠根尖周组织;牙髓暴露7~21 d,根尖周结缔组织中整合素β1呈阳性至强阳性表达,炎细胞密集区可见深棕色颗粒集聚;牙髓暴露28 d,根尖周结缔组织中整合素β1表达较弱。牙槽骨内的骨细胞、陷窝内血管、成骨细胞、破骨细胞及牙骨质细胞中整合素β1在牙髓暴露0~14 d呈强阳性表达,21 d后表达减弱。结论 整合素β1参与根尖周炎症的进展与根尖周肉芽组织形成炎症早期的骨吸收。     

Toll like receptor 4 and membrane-bound CD14 expressions in gingivitis, periodontitis and CsA-induced gingival overgrowth

Objective

Immune cell recognition of lipopolysaccharides via CD14 and Toll-like receptor 4 (TLR4) complexes plays a crucial role in linking innate and adaptive immune responses. This study was aimed to investigate the expression of TLR4 and membrane-bound CD14 (mCD14) in the gingival tissues of patients with gingivitis, periodontitis and CsA-induced gingival overgrowth.

Design

Gingival tissues were obtained from 10 renal transplant patients receiving cyclosporine-A (CsA) and having gingival overgrowth (GO), 10 patients with chronic periodontitis, 10 generalized aggressive periodontitis, 10 gingivitis and 10 healthy subjects. Immunohistochemistry was performed in order to determine the localization of TLR4 and mCD14 in tissue specimens.

Results

TLR4 and mCD14 expressions were detected in all tissues including healthy gingival biopsies. TLR4 and mCD14 positive cells were predominantly confined to the epithelium–connective tissue interface area, and were highly expressed in the basal cell layer of patients with CsA GO and chronic periodontitis, compared to healthy group (P < 0.05).

Conclusion

The present study suggests that TLR4 and mCD14 protein expressions may be interrelated and appear to be associated with periodontal disease. CsA usage seemed not to affect TLR4 and mCD14 expressions in CsA induced GO tissues.     

Innate Immune Receptor Expression in Peri‐Implant Tissues of Patients With Different Susceptibility to Periodontal Diseases

Background: Although inflammation mediates the pathogenesis of periodontal diseases, the effects of innate immune responses on implant therapies have not been evaluated. Innate immune receptors, including toll‐like‐receptors (TLRs) and the receptor for advanced glycated end‐products (RAGE), are upregulated within inflamed gingiva and are responsible for initiation of detrimental host responses. The aim of this study is to compare the expression of TLR2, TLR4, and RAGE in gingival tissues from participants susceptible to periodontitis and participants not susceptible to periodontitis before and after implant therapy. Methods: Periodontally healthy participants received implant therapy for non‐periodontal edentulism. Participants susceptible to periodontitis were diagnosed with chronic periodontitis prior to implant therapy. Gingival biopsies were collected from edentulous ridges before implant installation and from peri‐implant mucosa 2 months after treatment. Histology, real‐time PCR, and Western blot were used to evaluate levels of inflammatory infiltrate, TLR2, TLR4, and RAGE expression. Results: Before implant therapy, elevated levels of RAGE were detected in gingival tissues from participants susceptible to periodontitis when compared to those from participants with healthy periodontiums, whereas no differences in the expression of TLR2 or TLR4 were detected. After implant therapy, there was an upregulation of RAGE and TLR4 levels that coincided with a downregulation of TLR2 levels in biopsies from participants susceptible to periodontitis. Levels of RAGE and TLR4 remained unchanged in biopsies from participants with healthy periodontiums, whereas TLR2 levels were significantly upregulated. Histologically, post‐implant biopsies from participants susceptible to periodontitis displayed higher levels of inflammatory infiltrate. Conclusion: Elevated levels of inflammatory potential were found after implant therapy in participants susceptible to periodontitis.     

Immunohistochemical localization of Toll-like receptors 2 and 4 in gingival tissue from patients with periodontitis

The present study investigated the expression of Toll-like receptor (TLR) 2, TLR4, cluster of differentiation (CD) 14 and CD1a in human periodontitis gingiva using immunohistochemical methods. The specimens were classified according to the degree of inflammation into three groups (mild, moderate and severe). We established three zones in which to evaluate the ratios of TLR2-, TLR4-, CD14- and CD1a-positive cells to total cells in the connective tissues of each section. TLR2 and TLR4 were expressed in human periodontal tissues, and the ratio of TLR2-positive cells was highest overall in zone 1 (connective tissue subjacent to pocket epithelium) of the severe group and that of TLR4-positive cells was higher in the severe group than in the other groups. These results suggest that TLR2 and TLR4 participate in the innate immune response to stimulation by bacterial products in periodontal tissues. The ratio of CD14-positive cells was lowest overall in zone 1 of the severe group and that of CD1a was higher in the severe group than in the other groups. These results suggest that CD14 may be down-regulated during the development of inflammation and/or dendritic cells might infiltrate chronically inflamed gingival tissue.     

Immunohistochemical localization of Toll‐like receptors 2 and 4 in gingival tissue from patients with periodontitis

The present study investigated the expression of Toll‐like receptor (TLR) 2, TLR4, cluster of differentiation (CD) 14 and CD1a in human periodontitis gingiva using immunohistochemical methods. The specimens were classified according to the degree of inflammation into three groups (mild, moderate and severe). We established three zones in which to evaluate the ratios of TLR2‐, TLR4‐, CD14‐ and CD1a‐positive cells to total cells in the connective tissues of each section. TLR2 and TLR4 were expressed in human periodontal tissues, and the ratio of TLR2‐positive cells was highest overall in zone 1 (connective tissue subjacent to pocket epithelium) of the severe group and that of TLR4‐positive cells was higher in the severe group than in the other groups. These results suggest that TLR2 and TLR4 participate in the innate immune response to stimulation by bacterial products in periodontal tissues. The ratio of CD14‐positive cells was lowest overall in zone 1 of the severe group and that of CD1a was higher in the severe group than in the other groups. These results suggest that CD14 may be down‐regulated during the development of inflammation and/or dendritic cells might infiltrate chronically inflamed gingival tissue.     

The in vivo expression of membrane-bound CD14 in periodontal health and disease

BACKGROUND: Membrane-bound CD14 (mCD14) is a myeloid differentiation antigen expressed on monocytes/macrophages and neutrophils. It is a key molecule responsible for the innate recognition of bacteria by host cells and functions as an important receptor for bacterial lipopolysaccharide. This study investigated the in vivo expression profile and levels of mCD14 in healthy and diseased gingival tissues. METHODS: Gingival biopsies were obtained from 24 patients with chronic periodontitis, including 22 periodontal pocket tissues, 13 clinically healthy tissues, and 18 inflamed connective tissues (i.e., granulation tissues). Gingival biopsies from seven periodontally healthy subjects were used as controls. mCD14 was detected by immunohistochemistry. RESULTS: mCD14 was detected in 21 of 22 periodontal pocket tissues and all other categories of tissues. The mCD14-positive cells were mainly confined to the gingival epithelium-connective tissue interface. The expression levels in periodontally healthy subjects were significantly higher than in the patients. Within the patients, clinically healthy tissues showed greater levels of mCD14 than periodontal pocket tissues and granulation tissues. CONCLUSIONS: mCD14 was commonly expressed in both healthy and diseased gingival tissues and was predominantly confined to the epithelium-connective tissue interface. The positive relationship observed between mCD14 expression levels and periodontal health may imply that mCD14 is associated with favorable host responses to bacterial challenge and contributes to maintaining periodontal homeostasis.     

Expression of transient receptor potential vanilloid receptor 1 and toll-like receptor 4 in aggressive periodontitis and in chronic periodontitis

Öztürk A, Y?ld?z L. Expression of transient receptor potential vanilloid receptor 1 and toll‐like receptor‐4 in aggressive periodontitis and in chronic periodontitis. J Periodont Res 2011; 46: 475–482. © 2011 John Wiley & Sons A/S Background and Objective: The objective of the present study was to evaluate the expression and the distribution of the transient receptor potential vanilloid receptor 1 (TRPV1) and of toll‐like receptor 4 (TLR4) in tissue samples from patients with periodontal disease (aggressive periodontitis and chronic periodontitis) and from healthy controls. Material and Methods: Ten tissue samples from each disease group (aggressive periodontitis and chronic periodontitis) and from healthy subjects were obtained during routine oral surgical procedures. Subgingival specimens were collected from sites with advanced loss of support (probing depth > 5 mm) and specimens from the corresponding healthy controls were obtained during tooth extraction for orthodontic reasons or following surgical extraction of an impacted third molar. The distribution of TRPV1 and TLR4 receptors in human gingival tissue was studied by immunohistochemistry. Results: Both TLR4 and TRPV1 were detected in gingival tissues from healthy subjects, and from patients with chronic periodontitis and aggressive periodontitis, particularly in gingival keratinocytes, fibroblasts, inflammatory cells and the endothelial lining of capillaries in connective tissues. Histologic examination of the samples from healthy controls disclosed that clinically healthy gingiva does not correspond to histologically healthy gingiva. Subsequently, these samples were redesignated as gingivitis samples. TRPV1 was down‐regulated in all cell types in samples obtained from patients with chronic periodontitis compared to samples obtained from patients with gingivitis, whereas TLR4 was down‐regulated only in the epithelium and in gingival fibroblasts. In contrast, the levels of these markers in patients with aggressive periodontitis were similar to those in healthy patients. Conclusion: Local expression of TRPV1 and TLR4 in gingival tissues may contribute to both physiological and pathological processes in the periodontium. Our data suggest that TRPV1 and TLR4 may play a role specifically in the pathophysiology of chronic periodontitis.     

Expression of toll-like receptors 2, 4 and 9 is increased in gingival tissue from patients with type 2 diabetes and chronic periodontitis

Rojo‐Botello NR, García‐Hernández AL, Moreno‐Fierros L. Expression of toll‐like receptors 2, 4 and 9 is increased in gingival tissue from patients with type 2 diabetes and chronic periodontitis. J Periodont Res 2012; 47: 62–73. © 2011 John Wiley & Sons A/S Background and Objective: Broad evidence indicates that diabetes both increases the risk and hastens the progression of periodontal disease. Likewise, chronic inflammation or infections seem to provoke insulin resistance and thereby contribute to the development of diabetes and its complications. Innate immune responses, which appear to be altered in individuals with diabetes, are usually mediated by the recognition of pathogens through toll‐like receptors (TLRs). The constitutive expression of some TLRs has been reported in healthy human gingival tissue. Interestingly, the expression of TLRs 2 and 4 is increased with the severity of periodontal disease. Considering that the inflammatory reaction is exacerbated in individuals with diabetes and periodontitis, we suspected that the expression of some TLRs might be increased in gingival tissue in these patients. Material and Methods: In this study, we analyzed, by immunofluorescence, the expression of TLRs 2, 3, 4 and 9 in gingival tissues from healthy individuals and from periodontal patients with or without type 2 diabetes. Results: We found that the expression levels of TLRs 2, 3, 4 and 9 were higher in all periodontal patients than in healthy individuals. The expression of some TLRs was increased in subjects with periodontitis and diabetes relative to subjects with periodontitis but without diabetes; this increase in expression was found particularly in TLR2 and TLR9 in the connective tissue and in TLR4 at the epithelial region. Conclusion: These data suggest that the expression of these TLRs 2, 3, 4 and 9 in gingival tissue is higher in individuals with diabetes because its inflammatory reaction is exacerbated. Additionally, the expression of these TLRS is positively regulated with the severity of periodontal disease.