Role of Helicobacter pylori flagella in mediating host immune responses

• Main Authors: Chung-Cheng Lin, 林忠誠
• Other Authors: Lin-Li Chang
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/xb5m46

碩士 === 高雄醫學大學 === 醫學研究所碩士班 === 105 === Abstract Background: It has been known that mucosal stromal cells represent a crucial component of the cancer microenvironment. The molecular mechanisms by which H. pylori infected gastric stromal cells and a subsequent response with DCs remain unclear. The current study was to investigate whether flagella and LPS of H. pylori will interact with the gastric stromal cells and influence the IL-10 secretion from DC. Methods: In this study, peripheral blood mononuclear cells (PBMCs) were isolated from healthy individuals with no history of H. pylori infection. Then induced immature DCs in the presence of IL-4 and GM-CSF within 5–7 days. Gastric stromal cells were obtained from three gastric cancer patients (T21, T2, T9) and one gastritis patient (N1). H. pylori J99 and flagella mutant strains ΔcsrA、ΔcsrA- revertant、ΔrpoN, and LPS mutant strains FutA、FutB、FutC of H. pylori(26695) were used. Level of IL-10 secreted from DCs was measured when DCs were co-cultured with H. pylori-primed GSCs. Results: Increased level of IL-10 secretion from DCs was found when DCs were co-cultured with Hp-primed GSCs. However, when flagella mutant strains of Hp (J99 ΔcsrA, J99 ΔcsrA-revertant and J99ΔrpoN) were used to stimulate GSCs, the IL-10 expression in DCs was not significantly difference with wild type strain J99. In addition, the DC-priming effect and IL-10 secretion was not different when LPS was obtained from gastric cancer (CA) or gastric ulcer (GU) patients. Conclusion: Weak immunogenic antigens of Helicobacter flagella and LPS do not play roles in priming gastric stromal cells and effecting immune responses of DCs. Therefore, H. pylori can evade host immune responses, persist localize in the gastric mucosa and development of chronic gastric diseases.