DC-SIGN在幽门螺杆菌感染的表达及其可能作用机制探讨

Research on expression of DC-SIGN in Helicobacter pylori infection and its possible mechanisms

目的探究DC-SIGN(DC-specific ICAM-3-g rabbing nonintegrin,CD209)在幽门螺杆菌感染的表达情况及其可能作用机制。方法选取2013年6月-2019年1月台州市第一人民医院收治的慢性胃炎患者90例为慢性胃炎组,同期选择健康体检者30名为对照组,检测幽门螺杆菌感染情况;比较两组的DC-SIGN表达(免疫组织化学法),比较分析对照组、幽门螺杆菌阴性、幽门螺杆菌阳性、慢性胃炎组的Toll样受体表达(荧光定量PCR法)、Th1、Th2细胞含量、白细胞介素-2(Interleukin-2,IL-2)、γ-干扰素(Interferon-γ,IFN-γ)细胞因子水平。结果慢性胃炎组的胃黏膜DC-SIGN表达阳性率57.78%高于对照组的0(P<0.05);幽门螺杆菌阳性者的DC-SIGN表达阳性率72.41%高于阴性者的31.25%(P<0.05);慢性胃炎组的TLR2(1.56±0.38)、TLR4(1.43±0.32)高于对照组(P<0.05);幽门螺杆菌阳性者的TLR2(1.89±0.42)、TLR4(1.86±0.36)高于阴性者(P<0.05);慢性胃炎组的Th1细胞比例(7.65±2.73)%高于对照组,Th2细胞比例(1.60±0.63)%低于对照组(P<0.05);幽门螺杆菌阳性者的Th1细胞比例(8.69±3.79)%高于阴性者,Th2细胞比例(1.54±0.57)%低于阴性者(P<0.05);慢性胃炎组的IFN-γ水平(19.24±3.89)pg/ml高于对照组,IL-4水平(1.83±0.30)pg/ml低于对照组(P<0.05);幽门螺杆菌阳性者的IFN-γ水平(20.28±3.17)pg/ml高于阴性者,IL-4水平(1.74±0.26)pg/ml低于阴性者(P<0.05)。结论患者感染幽门螺杆菌后,DC-SIGN表达明显升高,可能通过与Toll样受体间的相互作用,诱导T细胞向Th1分化,Th1优势应答,IFN-γ分泌增加,进一步破坏Th1/Th2平衡。

OBJECTIVE To investigate the expression of DC-SIGN in Helicobacter pylori infection and its possible mechanisms.METHODS From June 2013 to January 2019,90 patients with chronic gastritis admitted to Taizhou No.1 People’s Hospital were divided into the chronic gastritis group,and 30 health volunteers under physical examination during the same period were enrolled as the control group.The H.pylori infection test was performed on all subjects.The level of DC-SIGN expression detected by immunohistochemical method was compared between the two groups.Toll-like receptor expression was detected by fluorescent quantitative PCR;Th1,Th2 cell content,IL-2,IFN-γcytokine levels was obtained by ELISA.RESULTS The positive rate of DC-SIGN in gastric mucosa of patients in chronic gastritis group was 57.78%,which was significantly higher than that in the control group(P<0.05).The positive rate of DC-SIGN in HP positive group was 72.41%,which was significantly higher than that in the HP negative group(P<0.05).Levels of TLR2(1.56±0.38)and TLR4(1.43±0.32)in the chronic gastritis group were significantly higher than that in the control group(P<0.05).Levels of TLR2(1.89±0.42)and TLR4(1.86±0.36)in the H.pylori positive group were significantly higher than that in the negative group(P<0.05).The percentage of Th1 cells in the chronic gastritis group was(7.65±2.73)%,which was significantly higher than that in the control group,and the percentage of Th2 cells in the chronic gastritis group was(1.60±0.63)%,which was significantly lower than that in the control group(P<0.05).The percentage of Th1 cells in H.pylori positive patients was(8.69±3.79)%,which was significantly higher than that in the negative patients,and the percentage of Th2 cells was(1.54±0.57)%,which was lower than that in the negative patients(P<0.05).The level of IFN-γ(19.24±3.89)pg/ml in the chronic gastritis group was higher than that in the control group,and the level of IL-4(1.83±0.30)pg/ml was significantly lower than that in the control group(P<0.05).The levels of IFN-γ(20.28±3.17)pg/ml and IL-4(1.74±0.26)pg/ml in H.pylori positive patients were significantly higher than that in the negative patients(P<0.05).CONCLUSION After the infection with H.pylori,the expression of DC-SIGN increased significantly,which may induce T cells differentiate into Th1 through the interaction with Toll-like receptors.The secretion of IFN-γincreased,so as to induce the imbalance of Th1/Th2.