The Correlation Between Th Subsets With Their Signature Cvtokines And The Chronic Periodontitis

Chronic periodontitis (CP) is multifactorial infectious disease of supporting structures of the teeth. It is believed that cell mediated immune response to some oral micro-organisms plays the role in CP pathogenesis. Specifically, activated CD4+T-cells express receptor activator of nuclear factor kappa-B ligand (RANKL), which can directly trigger osteoclastogenesis and alveolar bone loss associated with periodontitis. Naive CD4+T cells can be divided into different T cell subsets based on their polarized patterns of cytokine secreted, which include Th1,Th2, Treg and Th17cells. A flurry of human studies supports the notion that the "protective Th1/destructive Th2" model failed to adequately reflect T-cell-mediated immune reponses. Recently, a relatively new member of the CD4+effector T-cell family (Th17cells) was recognized as key determinant in host defense against extracellular microbial infection and autoimmune diseases, which explains in part the deficiencies of the classic Th1/Th2paradigm.Furthermore, Th17cells have been classified as classical or alternative phenotype. But their pathogenicity in periodontal diseases, the difference of ability in promoting osteoclast activity, and the regulatory mechanism of cytokine secretion are still unknown. Effects of IFN-γ and IL-17secreated by Thl and Thl7on pro-osteoclast cell proliferation, differentiation and apoptosis, provide preliminary basis for the immune mechanism of periodontal disease.The expected result may provide a new theoretical explanation on the relationship between the periodontitis and host immune, as well as offer new perspectives to guide the clinical strategy for the prevention and treatment of peridontal disease.There are three sections following:Section1:The expression of Thl/Th2/Th17cells and their specific cytokines in patients with Chronic PeriodontitisObjective:Th17cells as a novel effector T-cell population offered a new insight to the classic Thl/Th2model for interpreting the pathogenesis of periodontitis. However, the clarifying role of Th1/Th2/Th17cells and their specific cytokines in periodontal disease are still not clear. The present study aimed to evaluate the role of Th cells and related cytokines in chronic periodontitis (CP).Methods:Sixty-eight patients with chronic periodontits and forty-three controls were included in our present study. The frequency of peripheral Th1,Th2and Th17cells in peripheral blood were analyzed by flow cytometry.The concentration of interleukin-2(IL-2), IL-4, IL-6, IL-10, IL-17, TNF, and IFN-y were determined using a flow cytometric Bead Array (CBA).Results:The percentage of circulating Thl were significantly higher in moderate and severe CP subjects (13.2±6.91%,16.6±1.07%respectively) when compared to normal subjects (8.22±4.50%,; P<0.05) based on cytokine patterns after in vitro activation by PMA/ionomycin. In addition, the frequencies of Th17cells were also higher in patients with CP (0.95±0.84%,1.39±0.9%respectively) than those in normal controls (0.62±0.49%, P<0.05). Comparisons of two groups of Thl/Th2/Thl7cytokine levels in plasma and GCF showed no significant differences (P>0.05), except IL-17level in plasma that was higher in the periodontitis group than the healthy group (P<0.05). A stronger correlation between IL-17/IL-4and IL-17/IL-10was observed in periodontitis patients than in healthy controls. Conclusion:Our data suggest that the elevated peripheral Th17and Thl cells may be synchronically associated with the development of chronic periodontitis. It suggested that IL-17might be associated with chronic periodontitis by recruiting immune cells required to the spread of periodontal inflammation.Section2:Thl and Th17cells in lesions of chronic periodontitis and distribution of IL-17+IFN-γ+Th17cellsObjective:This present study aimed to evaluate the possible role of Thl and Th17cells in chronic periodontitis lesions. Moreover, expression of peripheral blood mononuclear cells IL-17+IFN-γ+Th17were detected by flow cytometry.Methods:Twenty patients with chronic periodontits and eleven controls were included in our present study. Immunohistological analysis of IL-17and IFN-γ expression was conducted to identify Thl and Thl7cells in CP lesions. In addition, the mRNA levels of interleukin-17(IL-17), interferon-gamma(IFN-γ), RORyt, and T-bet in gingival biopsy sample were measured by quantitative real-time polymerase chain reaction, which were the specific transcription factor for Th1and Th17, respectively.Results:Immunohistochemical staining for IL-17and IFN-y protein in gingival biopsy, the expression markly increased in patients with CP when compared with that in the control subjects(397.8±42.9vs204.8±28.1and385.8±34.5, vs206.1±29.9respectively; P<0.05). The relative mRNA level of IFN-y, IL-17A,and T-bet in patients were higher in chronic periodontitis than that in healthy controls (P<0.05). In addition, the percentage of IL-17+IFN-γ+Th17cells in peripheral blood of chronic periodontitis is higher, but there was no significant differences.Conclusion:Our data suggest that the elevated peripheral Th17and Thl cells may be synchronically associated with the development of chronic periodontitis. Section3:Influence of IL-17and IFN-y on murine RAW264.7cellsObjective:IL-17and IFN-y are known to influence osteoclast formation and bone resorption. In order to investigeted the biological effects of administered both IL-17and IFN-γ on murine RAW264.7cells in vitro.Methods:Murine RAW264.7cell line was induced into osteoclasts with M-CSF and RANKL. Then were cultured in medium with IL-17A with or without IFN-γ respectively. Viability was determined using cell counting kit-8. The percentage of relative activity was also tested by Tartrate resistant acid phosphatase(TRAP) kit. RT-PCR is used to examine the expression of related specific gene. Furthermore, cell apoptosis was analyzed using flow cytometer.Results:TRAP staining, osteoclast specific gene detection indicated RAW264.7cells could be induced into mature osteoclast. IFN-y inhibit the proliferation of pre-osteoclast with dose-dependent manner. The expression of NFATcl、CathK and c-fos significantly decreased in both IL-17and IFN-y than stimulated by RANKL. The apoptosis rate of osteoclast was significantly higher in IFN-y with and without group. IFN-y promotes osteoclast precursor cell apoptosis through Fas/FasL. IL-17significantly inhibit IFN-γ-induced RAW264.7apoptosis in vitro.Conclusion:IL-17and IFN-γ were secreted Th1/Th17cells simultaneously. IL-17significantly inhibit IFN-γ-induced RAW264.7apoptosis, which suggest that it plays a key role in periodontal diseases...