Porphyromonas gingivalis infection-associated periodontal bone resorption is dependent on receptor activator of NF-κB ligand.

Porphyromonas gingivalis is one of the oral microorganisms associated with human chronic periodontitis. The purpose of this study is to determine the role of the receptor activator of nuclear factor-κB ligand (RANKL) in P. gingivalis infection-associated periodontal bone resorption. Inbred female Rowett rats were infected orally on four consecutive days (days 0 to 3) with 1 × 10(9) P. gingivalis bacteria (strain ATCC 33277). Separate groups of rats also received an injection of anti-RANKL antibody, osteoprotegerin fusion protein (OPG-Fc), or a control fusion protein (L6-Fc) into gingival papillae in addition to P. gingivalis infection. Robust serum IgG and salivary IgA antibody (P < 0.01) and T cell proliferation (P < 0.05) responses to P. gingivalis were detected at day 7 and peaked at day 28 in P. gingivalis-infected rats. Both the concentration of soluble RANKL (sRANKL) in rat gingival tissues (P < 0.01) and periodontal bone resorption (P < 0.05) were significantly elevated at day 28 in the P. gingivalis-infected group compared to levels in the uninfected group. Correspondingly, RANKL-expressing T and B cells in rat gingival tissues were significantly increased at day 28 in the P. gingivalis-infected group compared to the levels in the uninfected group (P < 0.01). Injection of anti-RANKL antibody (P < 0.05) or OPG-Fc (P < 0.01), but not L6-Fc, into rat gingival papillae after P. gingivalis infection resulted in significantly reduced periodontal bone resorption. This study suggests that P. gingivalis infection-associated periodontal bone resorption is RANKL dependent and is accompanied by increased local infiltration of RANKL-expressing T and B cells.

Bisphosphonates-related osteonecrosis of the jaws: a preliminary study of salivary interleukins.

OBJECTIVE: The aim of this preliminary study was analyze the possible alterations in some salivary interleukins, usually associated with the inflammatory processes. MATERIAL AND METHODS: The study comprised three groups: group 1, with 26 cases with bisphosphonates-related osteonecrosis of the jaws (BRONJ). Group 2, with 29 patients who had received iBF but without BRONJ. Group 3, with 26 control patients not treated with BF and without oral lesions. We collected unstimulated whole saliva in all groups. A semiquantitative study was performed based on a cytokine array panel. We used the proteome profiler array for the study. We analyzed: Interleukin 1 alpha (IL-1α), interleukin-1 receptor antagonist (IL-1RA), and interleukin 1 beta (IL-1ß). RESULTS: We found higher salivary values for all the cytokines studied in group 1 than in group 2 and 3. IL-1ß showed the major differences compared with control group. (P < 0.05) CONCLUSIONS: This preliminary study confirms that there are alterations in these interleukins in patients with BRONJ. These results give support to further additional salivary studies on these biomarkers by quantitative measures.

[Clinical immunological peculiarities of complicated course of odontogenic phlegmons of maxillofacial region].

Based upon clinical immunological checkup of 76 patients with common phlegmons of maxillofacial region, their complications and analysis of general phlogogenic activity the variants of hyperergic inflammation process flow were determined, that allowed to diagnose its activity and forecast possibility of its further development and its outcome.

[Some cytokines and cytokines autoantibodies content in the blood serum, oral and gingival fluid in odontogenic maxillofacial abscesses].

Cytokines level and cytokines antibodies in the blood serum, oral and gingival fluids was studied in 15 patients with odontogenic maxillofacial abscesses. Increased level of the inflammatory cytokines (IL1ß, IL6, IL8) and decreased level of the anti-inflammatory cytokines (IL4, IL10) in oral and dentigingival fluids. Besides, increased content of autoantibodies of class sIgA to IL8 and decreased content of autoantibodies of class sIgA to IL10 was noted.

The essential role of IFN-gamma in the control of lethal Aggregatibacter actinomycetemcomitans infection in mice.

Inflammatory immune reactions in response to periodontopathogens trigger periodontal destruction, but their role to protect the host against infection remains unknown. Thus, we examined the mechanisms by which IFN-gamma modulates the outcome of Aggregatibacter actinomycetemcomitans-induced periodontal disease in mice. Our results showed that IFN-gamma deficient mice developed less severe periodontitis in response to A. actinomycetemcomitans infection, characterized by significant lower alveolar bone loss and inflammatory reaction. However, the absence of IFN-gamma results in increased bacterial load in periodontal tissues and higher acute phase reaction, followed by a disseminated bacterial infection and mice death during the course of the disease. Such impaired host response was found to be associated with a reduction in the levels of inflammatory cytokines and chemokines and in the number of GR1+, F4/80+, CD4+ and CD8+ leukocytes in the diseased periodontium of IFN-gamma deficient mice. In addition, the levels of both antimicrobial mediators myeloperoxidase and inducible nitric oxide synthase were also found to be reduced in IFN-KO mice. Our results demonstrate for the first time that a periodontal infection may be lethal in an immunocompromised host. In addition, the mechanisms involved in IFN-gamma mediated cell migration to diseased periodontal tissues, and its essential role to control A. actinomycetemcomitans infection were clarified.

Interleukin-17: a new paradigm in inflammation, autoimmunity, and therapy.

Chronic diseases, such as periodontal disease (PD) and rheumatoid arthritis (RA), are characterized by a robust immune response resulting in unresolved inflammation. Inflammation is mediated by proinflammatory cytokines; recently, a novel subset of T-helper (Th) cells was identified that plays a crucial role in inflammation and autoimmune disease. This population secretes several proinflammatory cytokines, including the novel cytokine interleukin (IL)-17, and, hence, has been termed "Th17." Inflammatory cytokines are implicated in the progression of localized chronic infections, such as PD, and in serious systemic pathologies, such as diabetes, chronic obstructive pulmonary disease, and cardiovascular disease. IL-17 mediates inflammation through a receptor (IL-17R) composed of two subunits, IL-17RA and IL-17RC. Drugs that antagonize inflammatory cytokines are used therapeutically to downregulate immune-mediated pathology in conditions such as RA, although not all patients respond well to this approach. Therefore, identification of potential novel therapeutic targets, such as the IL-17 signaling complex, may be clinically relevant for mitigating inflammatory pathology. However, the manner in which such a therapeutic may influence the onset and progression of PD is poorly understood. Therapeutics that antagonize inflammatory cytokines ameliorate inflammation and bone loss and may have broader implications for individuals with systemic diseases in which inflammation and autoimmunity predominate.

[Dynamics of immune status in patients with phlegmons of the maxillofacial area during endolymphatic antibiotic therapy]]. / Dinamika immunnogo statusa bol'nykh s flegmonami cheliustno-litsevoi oblasti pri éndolimfaticheskoi antibiotikoterapii.

Studies of immunotropic effects of ampicillin, gentamicin sulfate, lincomycin, and rifampicin SV used in endolymphatic therapy of patients with maxillofacial phlegmons demonstrated a pronounced immunomodulating effect of rifampicin SV in polygluquine. The immunomodulating effect of lincomycin was lower, and that of ampicillin virtually null. Gentamicin sulfate suppressed some parameters of the immune status.

Glandular odontogenic cyst in China: report of 12 cases and immunohistochemical study.

OBJECTIVE: The purpose of this study was to present 12 additional cases of glandular odontogenic cyst (GOC) in the Department of Oral Pathology, School of Stomatology, Wuhan University, People's Republic of China, and to investigate their immunohistochemical cytokeratins (CKs) expression in the epithelial components. METHODS: A total of 12 GOCs were reviewed clinically and radiographically, and immunohistologic CKs AE1, 7, 8/18, 10/13, 14, 16, 19 and 20 were performed by using a standard biotin-streptavidin immunoperoxidase technique on paraffin sections. RESULTS: The present series showed that eight occurred in males and four in females. The mean age was 37.6 years with a peak incidence occurring in the third decades (six of 12). Mandibles were more affected than maxillas (7:5), especially anterior mandible (four of seven). Radiographically, ratio multilocular to unilocular radiolucencies was 5:7 usually with well-defined borders. Histologically, cystic spaces were lined by non-keratinized stratified epithelia containing focal plaque-like or whirlpool-like thickenings; surface epithelial layer-containing eosinophilic cuboidal cells; mucous cells; and mucin pools of microcystic areas in the epithelium. Immunohistochemistry showed that epithelium of GOCs stained for CKs AE1, 7, 8/18, 10/13, 14 and 19 with slight changes in their patterns, and no reaction to CKs 16 and 20. CONCLUSIONS: Most clinical and histologic features in this study were analogous to those reported west population, although with slight difference between them. Histologically, the morphology of the epithelium strongly suggested an odontogenic origin, and CKs expression of GOC was similar to that of odontogenic epithelium, suggesting histochemically that GOC might be derived from odontogenic epithelium.

[Expression of certain cytokeratins in the epithelium of dentigerous and primordial cysts]. / L'expression de certaines cytokératines par l'épithélium de kystes dentigères et primordiaux.

The histopathologic diagnosis of odontogenic cysts is based mainly on the morphological nature of the epithelial lining of the cyst. A standard immunocytochemical method based on anticytokeratin monoclonal antibodies was used for the diagnosis of dentigerous and primordial cysts: 12 odontogenic cysts were diagnosed on clinical, radiological and pathological criteria in 9 dentigerous cysts and 3 primordial cysts. The anticytokeratin antibodies used in this study were KL1 (Immunotech, France) and AE1, AE2, AE3 and AE8 (ICN-Miles, France). The anticytokeratin antibodies used stained only the epithelial cells confirming their accuracy. The KL1 antibodies stained homogeneously the various epithelial cells. This positive reaction was not modified by the various fixation methods used. Some reactions observed with AE antibodies seemed to be modified by Bouin's fixative. The staining homogeneity of the primordial cysts and the staining heterogeneity of the dentigerous cysts seemed to be related to morphological aspects of their respective epithelia. The epithelial reactions in these 2 types of cysts towards inflammation were different.