Anti-cardiolipin and increased serum adhesion molecule levels in patients with aggressive periodontitis

BACKGROUND: We observed that a significant proportion of patients with periodontitis have elevated serum levels of beta2-glycoprotein-I-dependent anti-cardiolipin (anti-CL). These prothrombotic autoantibodies, commonly found to be elevated in patients with systemic lupus erythematosus and the antiphospholipid syndrome, are associated with adverse pregnancy outcomes, such as fetal involution, prematurity, and low birth weight, and with cardiovascular sequelae, such as atherosclerosis, stroke, and myocardial infarction. Anti-CL is known to promote vascular inflammation and thrombosis. METHODS: We measured serum levels of markers of vascular inflammation, including soluble intercellular adhesion molecule (sICAM)-1, soluble vascular cell adhesion molecule (sVCAM)-1, and sE-selectin, in 190 subjects with generalized aggressive or chronic periodontitis and in 90 periodontally healthy subjects. RESULTS: sVCAM-1 and sE-selectin levels were significantly higher in patients with elevated anti-CL (>15 U/ml). This relationship also was observed in the never-smoker subset of subjects, even after correction for demographic and periodontal variables. Within the diagnostic categories, sICAM-1, sVCAM-1, and sE-selectin were significantly higher in generalized aggressive periodontitis patients who had elevated anti-CL compared to those with normal anti-CL. Statistical correction for demographic and periodontal variables indicated that elevated anti-CL remained significantly associated with increased sVCAM-1 and sE-selectin in generalized aggressive periodontitis patients. CONCLUSIONS: Systemic markers of vascular inflammation in patients with aggressive periodontitis are associated with elevated levels of anti-CL. We hypothesize that a subset of periodontitis patients with elevated antiphospholipid antibodies could represent a subgroup at increased risk for obstetrical and cardiovascular sequelae.     

单核细胞趋化蛋白-1和细胞间黏附分子-1与动脉粥样硬化和牙周病的关系

以动脉粥样硬化为病理基础的冠心病是目前主要的致死性疾病之一，而牙周病与动脉粥样硬化之间存在着一定的相关性。单核细胞趋化蛋白（MCP）-1和细胞间黏附分子（ICAM）-1在动脉粥样硬化和牙周病的发生发展中起着重要的作用。本文就MCP-1和ICAM-1以及二者与动脉粥样硬化、牙周病间的关系作一综述。     

单核细胞趋化蛋白-1和细胞间黏附分子-1与动脉粥样硬化和牙周病的关系

以动脉粥样硬化为病理基础的冠心病是目前主要的致死性疾病之一,而牙周病与动脉粥样硬化之间存在着一定的相关性。单核细胞趋化蛋白(MCP)-1和细胞间黏附分子(ICAM)-1在动脉粥样硬化和牙周病的发生发展中起着重要的作用。本文就MCP-1和ICAM-1以及二者与动脉粥样硬化、牙周病间的关系作一综述。     

Response of human macrophage-like cells to stimulation by Fusobacterium nucleatum ssp. nucleatum lipopolysaccharide

Monocytes/macrophages are key members of the innate immune system and are present in higher numbers in active periodontal lesions than in inactive sites. The aim of this study was to characterize the response of human monocyte U937 cells, differentiated into adherent macrophages by treatment with phorbol-12-myristate 13-acetate, to stimulation by Fusobacterium nucleatum ssp. nucleatum lipopolysaccharide. Attachment of (3)H-lipopolysaccharide to macrophage-like cells was partially inhibited by anti-CD14 and anti-TLR4 polyclonal antibodies. Fusobacterial lipopolysaccharide did not cause cell apoptosis or block apoptosis induced by camptothecin. Lipopolysaccharide up-regulated the secretion of the pro-inflammatory cytokines interleukin-1beta, interleukin-6, and tumor necrosis factor-alpha as well as the chemokine interleukin-8 by macrophage-like cells. In addition, it increased phospholipase C and D activities, which likely contributed to the high levels of prostaglandin E(2) detected in the cell culture supernatant. Lastly, the amount of matrix metalloproteinase-9 produced by macrophage-like cells was significantly increased by the lipopolysaccharide treatment. Interestingly, fusobacterial cells acquired matrix metalloproteinase-9 activity following incubation in the presence of the culture supernatant of lipopolysaccharide-stimulated macrophage-like cells. In summary, the lipopolysaccharide of F. nucleatum ssp. nucleatum has a large array of biological effects on macrophage-like cells. This monocytic responsiveness to lipopolysaccharide may be a key regulator of periodontitis.     

Salivary immunoglobulin A directed to oral microbial GroEL in patients with periodontitis and their potential protective role

The aim of this study was to identify salivary immunoglobulin A (IgA) directed to oral microbial GroEL in patients with periodontitis and to demonstrate their potential protective role through a reduction of inflammatory cytokine production induced by microbial GroEL. Using five different proteins belonging to the heat-shock protein 60 family, Western immunoblot analysis of salivary IgA from 63 subjects revealed immunoreactivities with Campylobacter rectus GroEL and Porphyromonas gingivalis GroEL in subjects with periodontitis (P < 0.05) compared to control subjects. Using the BIACORE 1000 to measure the salivary IgA titers directed towards C. rectus GroEL, high resonance unit (RU) values were observed in the saliva samples from patients with periodontitis (P < 0.01). Furthermore, the number of teeth with deep pocket depth (>or=5 mm) showed a high correlation coefficient with the RU value (r = 0.50, P < 0.01). C. rectus GroEL possessed the ability to stimulate the production of interleukin-6 by gingival fibroblasts. Interestingly, salivary IgA antibody directed to C. rectus GroEL caused a partial inhibition of interleukin-6 production. This study showed a relationship between high levels of salivary IgA directed to GroEL and periodontal disease severity. Although additional investigations are required, salivary IgA to GroEL may have a protective role by reducing the inflammatory response induced by GroEL derived from periodontopathogenic bacteria.     

牙周炎对动脉粥样硬化影响的动物实验研究

目的建立牙周炎和动脉粥样硬化（AS）动物复合模型,探讨牙周炎对AS的影响。方法36只日本大耳白兔随机分为4组,包括单纯牙周炎（CP）组、牙周炎合并AS（CP+AS）组、单纯AS组和对照组,采用结扎结合涂牙龈卟啉单胞菌（P. gingivalis）的方法建立牙周炎动物模型,单侧髂动脉球囊内皮损伤术建立AS模型。建模成功后,采用苏木精-伊红（HE）染色观察样本的组织病理学改变;Elastica van Gieson（EVG）弹力纤维染色进行形态分析,计算髂动脉横断面内膜与中膜面积的比值。采用巢氏聚合酶链反应（PCR）法检测受损动脉壁中P.gingivalis 16S rDNA。酶联免疫吸附测定（ELISA）法检测系统炎性因子的表达,包括C反应蛋白（CRP）、白细胞介素-6（IL-6）和白细胞介素-1β（IL-1β）。结果CP+AS组的CRP、IL-6及IL-1β表达水平较其他组明显升高（P<0.01）,血管的内膜与中膜面积比均较其余组大（P<0.01）。在CP和CP+AS组的髂动脉中检出有P. gingivalis 16S rDNA存在。结论牙周炎对患AS
的动脉内膜的增厚可能起促进作用,其作用主要通过系统炎性因子的上调和细菌局部感染的作用来实现。     

T‐cell clonality to Porphyromonas gingivalis and human heat shock protein 60s in patients with atherosclerosis and periodontitis

Individuals with periodontitis have been reported to have a significantly increased risk of developing coronary heart disease. Several studies have demonstrated that the immune response to heat shock protein 60 (HSP60) may be involved in the pathogenesis of both atherosclerosis and chronic periodontitis. To investigate this possible link between these diseases, cellular and humoral immune responses to HSP60 in atherosclerosis patients were compared with those in periodontitis patients and healthy subjects using human and Porphyromonas gingivalis HSP60 (GroEL) as antigens. Antibody levels to both human and P. gingivalis HSP60s were the highest in atherosclerosis patients, followed by periodontitis patients and healthy subjects. Clonal analysis of the T cells clearly demonstrated the presence of not only human HSP60‐ but also P. gingivalis GroEL‐reactive T‐cell populations in the peripheral circulation of atherosclerosis patients. Furthermore, these HSP60‐reactive T cells seemed to be present in atherosclerotic lesions in some patients. These results suggest that T‐cell clones with the same specificity may be involved in the pathogenesis of the different diseases.     

Dendritic cells, antibodies reactive with oxLDL, and inflammation

Periodontitis appears to promote chronic inflammatory diseases, including atherosclerosis, but relevant mechanisms need clarification. Oral bacteria induce antibodies that bind not only bacteria, but also oxLDL. Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans induce remarkable IgG responses that are dominated by IgG2, and IgG2 is IFN-γ-dependent and is promoted by dendritic cells (DCs). LDL-reactive antibodies induced by P. gingivalis and A. actinomycetemcomitans include anti-phosphorylcholine (α-PC) and β2-glycoprotein-1-dependent anticardiolipin (α-CL), and these antibodies may link chronic inflammatory diseases at a mechanistic level. Antibody-mediated uptake of oxLDL or bacteria dramatically enhances DC-IL-12, and DC-IL-12 induces NK-cell-IFN-γ responses that promote Th-1 responses and sustained inflammation. DCs may be derived from monocytes, and this is striking in cultures of aggressive periodontitis (AgP) monocytes, where DC numbers are about double control levels. Moreover, serum α-CL levels in individuals with AgP are frequently elevated, and these antibodies promote atherosclerosis in persons with antiphospholipid syndrome. Elevated serum levels of soluble-intercellular adhesion molecule, soluble-vascular cell adhesion molecule, and soluble-E-selectin are atherosclerosis-associated indicators of vascular inflammation, and these markers are elevated in the subset of AgP patients with high α-CL. We reason that periodontitis patients with elevated antibodies reactive with oxLDL could be a subgroup at high risk for cardiovascular sequelae.     

Mouse model of experimental periodontitis induced by Porphyromonas gingivalis/Fusobacterium nucleatum infection: bone loss and host response

Aim: To compare the effect of oral infection with Porphyromonas gingivalis or Fusobacterium nucleatum versus infection with both bacteria on mouse periodontal tissues, and to characterize the inflammatory response.
Materials and Methods: Mice were orally infected with P. gingivalis, F. nucleatum or both. At 42 days post-infection, alveolar bone loss was quantified using micro-computerized tomography. Tumour necrosis factor- α (TNF- α ) and interleukin (IL)-1 β levels induced by the infection were quantified using the subcutaneous chamber model.
Results: Mice orally infected with F. nucleatum / P. gingivalis exhibited significantly more bone loss compared with that of mono-infected and sham-infected mice. F. nucleatum / P. gingivalis infection also increased the levels of TNF- α and IL1 β compared with the levels found in the mono-infected groups.
Conclusions: Polymicrobial infection with P. gingivalis / F. nucleatum aggravates alveolar bone loss and induces a stronger inflammatory response compared with that observed upon infection with either bacterium alone. The results suggest that oral infection of mice with a mixture of P. gingivalis and F. nucleatum may be superior to mono-infection models of experimental periodontitis.     

一氧化碳释放分子对牙周炎大鼠动脉粥样硬化的影响

目的 研究一氧化碳释放分子(carbon monoxide releasing molecule-2, CORM-2)对实验性大鼠牙周炎模型中动脉粥样硬化的作用。方法 40只8周龄Wistar大鼠,随机分为正常组、一氧化碳组(carbon monoxide group, CO组)、牙周炎组(chronic periodontitis group, CP组)和溶剂组(dimethylsulfoxide group, DMSO组)。CP组和CO组采用丝线结扎并注射内毒素法建立牙周炎模型。建模当天,CO组经腹腔注射CORM-2(10 mg/kg/d),DMSO组注射等体积DMSO溶液(0.05%V),正常组不做任何处理。分别于建模后1、3、7、14、28 d用酶联免疫吸附法检测血清内C反应蛋白(C-reactive protein, CRP)、可溶性血管细胞黏附分子1(soluble vascular cell adhesion molecule-1, sVCAM-1)、氧化型低密度脂蛋白(oxidized low density lipoprotein, ox-LDL)及白介素10( interleukin-10 ,IL-10)的含量。4周后处死大鼠,取大鼠降主动脉行油红O染色,观察脂质沉积情况,并检测牙槽骨吸收情况。采用SPSS 17.0软件包对所得数据进行统计学分析。结果 CO组大鼠牙周组织中炎细胞浸润及牙槽骨吸收程度均较CP组大鼠低,CP组大鼠血清CRP、sVCAM-1及ox-LDL水平显著高于CO组,CO组大鼠血清中IL-10水平显著高于其他各组（P<0.05）。28天后,在CP组大鼠降主动脉中可发现脂质沉积,而CO组大鼠血管中则无脂质沉积。结论 CORM-2能够抑制实验性牙周炎大鼠的炎性反应及动脉粥样硬化的形成。     

Periodontitis and diabetes interrelationships: role of inflammation

Diabetes mellitus is a systemic disease with several major complications affecting both the quality and length of life. One of these complications is periodontal disease (periodontitis). Periodontitis is much more than a localized oral infection. Recent data indicate that periodontitis may cause changes in systemic physiology. The interrelationships between periodontitis and diabetes provide an example of systemic disease predisposing to oral infection, and once that infection is established, the oral infection exacerbates systemic disease. In this case, it may also be possible for the oral infection to predispose to systemic disease. In order to understand the cellular/molecular mechanisms responsible for such a cyclical association, one must identify common physiological changes associated with diabetes and periodontitis that produce a synergy when the conditions coexist. A potential mechanistic link involves the broad axis of inflammation, specifically immune cell phenotype, serum lipid levels, and tissue homeostasis. Diabetes-induced changes in immune cell function produce an inflammatory immune cell phenotype (upregulation of proinflammatory cytokines from monocytes/polymorphonuclear leukocytes and downregulation of growth factors from macrophages). This predisposes to chronic inflammation, progressive tissue breakdown, and diminished tissue repair capacity. Periodontal tissues frequently manifest these changes because they are constantly wounded by substances emanating from bacterial biofilms. Diabetic patients are prone to elevated low density lipoprotein cholesterol and triglycerides (LDL/TRG) even when blood glucose levels are well controlled. This is significant, as recent studies demonstrate that hyperlipidemia may be one of the factors associated with diabetes-induced immune cell alterations. Recent human studies have established a relationship between high serum lipid levels and periodontitis. Some evidence now suggests that periodontitis itself may lead to elevated LDL/TRG. Periodontitis-induced bacteremia/endotoxemia has been shown to cause elevations of serum proinflammatory cytokines such as interleukin-1 beta (IL-1 beta) and tumor necrosis factor-alpha (TNF-alpha), which have been demonstrated to produce alterations in lipid metabolism leading to hyperlipidemia. Within this context, periodontitis may contribute to elevated proinflammatory cytokines/serum lipids and potentially to systemic disease arising from chronic hyperlipidemia and/or increased inflammatory mediators. These cytokines can produce an insulin resistance syndrome similar to that observed in diabetes and initiate destruction of pancreatic beta cells leading to development of diabetes. Thus, there is potential for periodontitis to exacerbate diabetes-induced hyperlipidemia, immune cell alterations, and diminished tissue repair capacity. It may also be possible for chronic periodontitis to induce diabetes.     

Severe periodontitis is associated with systemic inflammation and a dysmetabolic status: a case-control study

BACKGROUND AND AIM: A cluster of metabolic factors defines a syndrome that predisposes to diabetes and cardiovascular disease. Chronic infections such as periodontitis might alter these individual metabolic factors and the systemic inflammatory burden. The aim of this study was to investigate the association between severe periodontitis and increase in inflammatory and metabolic risk factors for cardiovascular disease. MATERIALS AND METHODS: We examined 302 patients with severe periodontitis and 183 healthy controls, and we collected a blood sample from each subject in order to investigate differences in inflammatory (leukocyte numbers and differential counts) and metabolic markers (lipids and glucose). RESULTS: After correcting for differences in age, gender, smoking and ethnicity, periodontitis subjects exhibited a low-grade systemic inflammation (increased white cell counts, 1.10+/-1.02 x 10(9)/l, 95%CI 1.05-1.15, p=0.0001), dyslipidemia [lower high-density lipoprotein cholesterol, 1.14+/-1.03 mmol/l, 95%CI 1.08-1.20, p<0.0001 and higher low-density lipoprotein cholesterol, 1.12+/-1.03, 95%CI 1.05-1.19, p<0.0001) and increased non-fasting serum glucose levels (1.04+/-1.01 mmol/l, 95%CI 1.02-1.06, p=0.01) when compared with controls. The associations were confirmed in a subpopulation of Caucasian non-smokers. A trend for a dose dependent effect of the number of periodontal pockets on the tested inflammatory and metabolic markers was observed. Conclusions: These data suggest a possible link between severe generalized periodontitis, systemic inflammation and a dysmetabolic state in otherwise healthy individuals.     

具核梭杆菌与牙周炎关系的研究进展

牙周炎是由多种微生物引起的感染性疾病。具核梭杆菌在牙周炎中有高检出率,两者有强相关性。具核梭杆菌可借助多种黏附素共聚致病菌、黏附侵入上皮细胞,利用毒力因子和代谢产物等破坏牙周组织,并可诱导宿主产生免疫反应,促进牙周疾病甚至全身系统性疾病的发生发展。但目前临床上辅助牙周基础治疗的药物并不能针对具核梭杆菌等特定牙周致病菌,可能会导致菌群失调或耐药等问题。具核梭杆菌致病机制的研究为牙周炎的预防及治疗提供了新的思路,研发针对具核梭杆菌黏附素、毒力因子、代谢产物或切断各个致病通路的材料、药物、益生菌产品,抑制其在深牙周袋中的增殖和炎症反应,保持与其他口腔微生物及宿主的动态平衡,有利于牙周炎的控制。     

T-cell clonality to Porphyromonas gingivalis and human heat shock protein 60s in patients with atherosclerosis and periodontitis

Individuals with periodontitis have been reported to have a significantly increased risk of developing coronary heart disease. Several studies have demonstrated that the immune response to heat shock protein 60 (HSP60) may be involved in the pathogenesis of both atherosclerosis and chronic periodontitis. To investigate this possible link between these diseases, cellular and humoral immune responses to HSP60 in atherosclerosis patients were compared with those in periodontitis patients and healthy subjects using human and Porphyromonas gingivalis HSP60 (GroEL) as antigens. Antibody levels to both human and P. gingivalis HSP60s were the highest in atherosclerosis patients, followed by periodontitis patients and healthy subjects. Clonal analysis of the T cells clearly demonstrated the presence of not only human HSP60- but also P. gingivalis GroEL-reactive T-cell populations in the peripheral circulation of atherosclerosis patients. Furthermore, these HSP60-reactive T cells seemed to be present in atherosclerotic lesions in some patients. These results suggest that T-cell clones with the same specificity may be involved in the pathogenesis of the different diseases.     

Effect of Periodontitis on Adiponectin,C‐Reactive Protein,and Immunoglobulin G Against Porphyromonas gingivalis in Thai People With Overweight or Obese Status

Background: Obesity and periodontitis are associated with an inflammatory background. Inflammatory mediators involved may have reciprocal effects on one another. In this study, the levels of inflammatory mediators implicated in overweight or obese status and periodontitis are simultaneously evaluated. Methods: Body mass index (BMI) and waist circumference, periodontal disease status, and plasma levels of adiponectin, leptin, intercellular adhesion molecule (ICAM)‐1, vascular cell adhesion molecule 1, C‐reactive protein (CRP), immunoglobulin (Ig)G antibody against Porphyromonas gingivalis, and IgG against Aggregatibacter actinomycetemcomitans in 109 periodontitis participants with various BMIs were measured. BMI ≥23.0 kg/m² was considered overweight or obese. Results: Plasma adiponectin was decreased (P = 0.04), whereas CRP and IgG against P. gingivalis were increased (P = 0.04 and P = 0.001, respectively) in patients with severe periodontitis compared with patients with mild or moderate periodontitis, independent of overweight or obese status. Plasma CRP, ICAM‐1, and leptin were increased (P <0.001, P = 0.007, and P <0.001, respectively) and adiponectin was decreased (P = 0.04) in overweight or obese participants compared with normal weight participants, without influence of periodontitis severity. No interaction effect between periodontitis and overweight or obese status existed for these protein levels after the data were adjusted for age, sex, plasma levels of triglycerides, high‐density lipoprotein cholesterol, fasting plasma glucose, and blood pressure (P = 0.48). Conclusions: Periodontitis and overweight or obese BMI change plasma levels of the inflammatory mediators adiponectin and CRP, independently. This study suggests a role of periodontitis in systemic inflammatory response in Thai people who are overweight or obese.     

不同孵育时间具核梭杆菌黏附和侵入上皮细胞的变化

目的：观察在具核梭杆菌（F.nucleatum，Fn）黏附和侵入上皮细胞的早期阶段，不同时间黏附量和侵入量的变化以及砌不同菌株之间黏附和侵入能力的差别。方法：将实验菌Fn ATCC10953以及Fn WCD05-1分别配成菌悬液，加入培养有上皮细胞（KB）的24孔细胞培养板中。孵育0．5、1、2、3、4h进行黏附和侵入测定。初步探索时间与砌黏附和侵入KB细胞的数量之间是否存在相关关系。结果：在黏附和侵入早期，随相互作用时间延长，砌黏附和侵入KB细胞的数量增加，并且临床株的黏附和侵入能力明显优于标准株。在达到最大黏附和侵入量以后，细菌量有一定下降，但是至少在短时间内可以保持一定的黏附和侵入水平。达到黏附和侵入的最大值时，临床株的黏附和侵入量分别约是标准株的2倍和4倍。结论：在黏附和侵入早期，随相互作用时间延长，砌黏附和侵入KB细胞的数量增加，并且临床株WCD05-1显示出比标准株ATCC10953更强的黏附和侵入能力。达到最大值后其黏附和侵入量有一定下降。     

长期低剂量牙龈卟啉单胞菌感染对脂蛋白基因敲除小鼠动脉粥样硬化形成的影响

目的 评价牙龈卟啉单胞菌(Porphyromonas gingivalis,Pg)口腔内低剂量、长期、多次接种是否可影响载脂蛋白基因敲除小鼠(apolipoprotein E-knocked out,ApoE-/-)的动脉粥样硬化(atherosclerosis,AS)形成进程和病变程度.方法 20只C57BL/6背景小鼠,将其中13只种属为C57BL/6背景的ApoE-/-小鼠按随机数字表随机分成两组,实验组7只使用1013个/L的牙周致病菌Pg进行口腔内涂菌接种,持续15周共75次,对照组6只同法口腔内涂擦无菌肉汤培养基,比较两组小鼠体质量、血总胆固醇、三酰甘油及主动脉AS病损面积及病理组织变化的情况.另7只野生型C57BL/6小鼠取其主动脉组织作为正常对照.结果 实验组ApoE-/-小鼠主动脉AS病损平均面积为(98 363.68±12 043.00)μm2,显著大于未接种的小鼠对照组[平均病损面积(62 985.06±7419.64)μm2],P=0.035;两组体质量、血总胆固醇和三酰甘油差异均无统计学意义;与野生型C57BL/6小鼠正常主动脉相比,ApoE-/-小鼠主动脉内壁均有凸向管腔内的AS病损,且动脉壁变平,实验组较对照组AS斑块更明显,动脉管腔更狭窄.结论 Pg口腔内低剂量长期多次接种可以加速ApoE-/-小鼠AS的进展.

Abstract：

Objective To assess the effect of longterm and lower oral inoculation with Porphyromonas gingivalis (Pg) on the progression of atherosclerosis in apolipoprotein E-knocked out (ApoE -/-) mice. Methods Six-week-old male ApoE -/- mice were inoculated orally with 0. 1 ml live Pg(1013/L) or bouillon culture-medium quintic per week for 15 consecutive weeks, altogether 75 times of inoculations. The lesion area of atherosclerosis in the aortic tree was measured by en face quantification by red oil O staining method. The atherosclerotic lesion was examined by histopathology. The levels of total cholesterol and triglycerides were compared. Results At 22 weeks after inoculation, the mean atherosclerotic lesion area in inoculated mice was (98 363.68 ± 12 043.00) μm2 ,which was significantly greater than that in noninoculated mice, which was (62 985.06 ± 7419. 64) μm2 (P = 0. 035).Conclusions Longterm lower oral inoculation of Pg can accelerate the progression of atherosclerosis in apolipoprotein E-knocked out mice.     

P. gingivalis and E. coli lipopolysaccharides exhibit different systemic but similar local induction of inflammatory markers

BACKGROUND: Porphyromonas gingivalis is a Gram-negative bacterium that is an important etiologic agent of human adult periodontitis. The goal of the study was to test the hypothesis that two isoforms of P. gingivalis lipopolysaccharide (PgLPS), PgLPS(1435)(/1449) and PgLPS(1690), exhibit differences in their capacity to stimulate systemic versus local responses compared to Escherichia coli lipopolysaccharide (LPS). METHODS: LPS was inoculated into the scalp of mice, and the response was measured locally at the site of inoculation and systemically in the heart/aorta. Vascular cell adhesion molecule (VCAM)-1 was assessed at the protein level by enzyme-linked immunosorbent assay, and VCAM-1, E-selectin, and intercellular adhesion molecule (ICAM)-1 were assessed at the RNA level of the RNase protection assay. Serum tumor necrosis factor-alpha (TNF-alpha) levels were also measured. RESULTS: E. coli LPS and both isoforms of P. gingivalis LPS were relatively potent in stimulating the expression of inflammatory markers, with E. coli LPS being more potent. In contrast, when the systemic response was measured in the heart/aorta, E. coli LPS, but not P. gingivalis LPS, significantly induced inflammatory markers. At moderate to low doses (1 and 10 microg per injection), serum TNF-alpha levels were minimally induced by P. gingivalis LPS compared to E. coli LPS. CONCLUSIONS: Both forms of P. gingivalis LPS stimulated an inflammatory response when injected into connective tissue but were minimally stimulatory when a systemic response was measured. In contrast, E. coli LPS was a potent stimulus at the systemic and local levels.     

Characterization of serum antibody to Actinobacillus actinomycetemcomitans GroEL-like protein in periodontitis patients and healthy subjects

Recent evidence suggests that molecular mimicry between bacterial and human heat shock protein 60 (hsp60) is involved in various conditions of autoimmune and infectious diseases. Many periodontopathic bacteria have been reported to express GroEL-like protein that is homologous to human hsp60. In this study, the presence of antibodies to the hsp60 of Actinobacillus actinomycetemcomitans in the sera of periodontitis patients and periodontally healthy control subjects was evaluated by enzyme-linked immunosorbent assay using a recombinant A. actinomycetemcomitans GroEL as an antigen. Furthermore, their cross-reactivity with Escherichia coli GroEL and Mycobacterium bovis BCG hsp65 was examined. The mean values of antibody were 0.624 (range 0.088-1.113) and 0.728 (range 0.217-1.296) in control subjects and periodontitis patients, respectively. The antibody levels to A. actinomycetemcomitans after absorption with E. coli GroEL and M. bovis BCG clearly decreased in both control subjects and periodontitis patients. The remaining antibody levels to A. actinomycetemcomitans GroEL after absorption with M. bovis BCG hsp65 were higher than those with E. coli GroEL, indicating higher cross-reactivity with E. coli GroEL. These results suggest that not only periodontitis patients but also periodontally healthy subjects may be infected with A. actinomycetemcomitans but that the part of the antibody could be derived from the cross-reactivity with E. coli GroEL. Any relationship of the antibody to the disease, however, remains to be determined.