转染自体胃癌细胞总RNA的树突状细胞诱导个体化免疫治疗的体外实验

目的探讨转染自体胃癌细胞总RNA的树突状细胞(DC)体外介导抗胃癌的免疫效应。方法制备短期培养的原代胃癌细胞。用rhGM-CSF、rhIL-4和TNF-α体外诱导胃癌患者外周血单个核细胞(PBMC)中DC的发育和成熟,并转染自体肿瘤细胞总RNA,激活自体T细胞产生CTL,用CCK-8试剂盒检测CTL的杀伤活性。应用流式细胞术及混合淋巴细胞培养技术检测DC的免疫功能状态。用ELISA法测定IL-12和INF-γ的水平。结果转染自体肿瘤细胞总RNA的成熟DC,不仅可高表达MHC-I、II类分子及CD80、CD83和CD86协同刺激分子,并可获得高效刺激自体或异体T细胞增殖的能力。转染RNA的成熟DC,分泌IL-12的水平及其刺激产生的CTL培养上清液中INF-γ的水平显著高于单纯成熟DC及未成熟DC;且CTL对自体胃癌细胞的杀伤率显著高于异体组。结论转染自体胃癌细胞总RNA的成熟DC能够体外诱导产生对自体肿瘤细胞具有高度抗原特异性杀伤活性的CTL。     

基于串口的胃阻抗信号采集处理

基于生物阻抗的胃动力信息提取是我们正在研究的一个重要项目。采用串口以及串口控件实现了信号采集，采用小波分析等现代信号处理方法，实现胃蠕动信号的提取和动态谱分析。由此方法研制的胃动力检测系统可在消化道生理、病理生理、药理及临床应用上发挥重要作用。     

胃癌患者血清Gastrin含量分析及临床意义

目的:探讨慢性浅表性胃炎、胃溃疡和胃癌患者血清胃泌素(Gastrin,Gas)的含量变化及意义。方法:采用放射免疫分析分别测定了40例慢性浅表性胃炎、42例胃溃疡患者及39例胃癌患者血清Gas水平并用38例健康人做对照。结果:慢性浅表性胃炎、胃溃疡及胃癌患者血清Gas含量分别为(96.99±19.80)ng/L,(99.61±26.39)ng/L和(128.58±21.39)ng/L,较健康对照组显著增高(P<0.01)。结论:血清Gas水平的变化与慢性浅表性胃炎、胃溃疡及胃癌的发生、发展密切相关。     

胃缺血-再灌注损伤对胃窦黏膜D细胞内生长抑素含量的影响

目的:研究胃缺血-再灌注损伤(gastric ischemia-reperfusion injury,GI-RI)对大鼠胃窦黏膜D细胞内生长抑素(somatostatin SS)含量的影响。方法:实验组大鼠分为单纯缺血组(ISO)、GI-R1 h、6 h、24 h和72 h组(I／R1-4),用免疫组织化学法及图像分析法对SS进行定量研究。结果:正常大鼠胃窦黏膜中D细胞主要分布于幽门腺的中、下1／3处,形态多样;而ISC组和I／R1组D细胞多为圆形,很少见有长的胞质突起;在I／R2-4组,则可见D细胞形态多样,并可见分布于幽门腺上1／3处。ISC组和I／R1组D细胞的数目显著少于对照组,细胞平均灰度值极显著大于对照组;而I／R2-4组D细胞的数目均显著多于对照组,仅I／R2组细胞平均灰度值极显著低于对照组。结论:胃窦黏膜中D细胞的形态数量及细胞内SS的含量在大鼠GI-RI过程中有变化,提示SS参与了GI-RI过程。     

佛波酯对人胃癌细胞Ha-ras基因启动子及启动子结合蛋白的影响

目的探讨佛波酯（PMA）对人胃癌细胞BGC-823 Ha—ras基因启动子活性及启动子结合蛋白活性的影响。方法通过RT-PCR和运用自行构建的真核表达载体prasEYFP转染细胞进行荧光细胞检测,并应用凝胶电泳移动检测、Southwestern blotting等方法检测PMA（100μg／L）处理BGC-823细胞72和96h后,对Ha—ras基因表达水平、Ha—ras基因启动子活性以及对Ha—ras启动子结合蛋白的影响。结果经PMA（100μg／L）处理72和96h,与未处理细胞相比,BGC-823细胞中Ha—ras基因表达显著降低,Ha—ras基因启动子活性分别被抑制65．2％和71．8％;同时两个Ha-ras启动子结合蛋白活性也显著降低,经检测,其分子量分别约为18kD,35kD。结论PMA长期处理通过降低人胃癌细胞中Ha—ras启动子结合蛋白活性使Ha—ras启动子活性被抑制,从而在转录水平上调节Ha—ras基因表达。     

胃癌细胞DNA含量和倍体分析的研究进展

利用流式细胞分析仪和图像细胞分析仪检测胃癌细胞核中DNA含量和倍体已成为病理诊断中的重要手段，DNA含量和倍体分析可用于胃癌前病变及早期胃癌的诊断，与胃癌的临床病理有密切的联系，可用于患者治疗效果的评估和预后的估计。     

Enhanced immunogenicity and antitumour effects with heterologous prime-boost regime using vaccines based on MG7-Ag mimotope of gastric cancer

MG7-Ag, gastric cancer-associated antigen, has been shown to be immunogenic and has been used as marker molecule for prognosis. In a previous study, we developed an oral DNA vaccine based on MG7-Ag mimotope. However, we failed to detect cellular immune response using the oral MG7-Ag mimotope DNA vaccine. To induce significant T cell response, we developed a recombinant adenovirus vaccine based on MG7-Ag mimotope and evaluated the efficacy and protective effects of heterologous prime-boost immunization protocol with an oral DNA vaccine previously developed. We found that both vaccines were able to elicit a significant humoral response against MG7-Ag, while the highest serum titre MG7 antibody was detected in mice immunized with the heterologous prime-boost immunization protocol. Enzyme-linked immunospot (ELISPOT) assay demonstrated that the heterologous prime-boost immunization strategy was more efficient in inducing T cell response than the homologous prime-boost strategy. In the tumour challenge assay, 2 of 5 mice immunized with the heterologous prime-boost protocol were tumour free, while none of the mice in homologous prime-boost groups or control groups was tumour free. Those tumour-bearing mice in the heterologous prime-boost regime had smaller tumour masses than their counterparts in the homologous prime-boost groups or control groups. Therefore, our study suggests that vaccines against MG7-Ag induce significant immune response against gastric cancer, and that the heterologous prime-boost protocol using different types of vaccines could achieve better protective effect than the homologous prime-boost protocol.     

Gastric mucin phenotype defines tumour progression and prognosis of intrahepatic cholangiocarcinoma: gastric foveolar type is associated with aggressive tumour behaviour

AIMS: To identify the role of mucus core protein (MUC) in intrahepatic cholangiocarcinoma (ICC). METHODS AND RESULTS: We examined the expression profile of MUC2, MUC5AC and MUC6 by immunohistochemical staining in 100 ICCs and compared the clinicopathological factors and the immunohistochemical results. The expression frequency was: MUC2, 9%; MUC5AC, 40%; and MUC6, 21%. According to the gastric mucin expression profile, ICCs were classified into the following groups: null type (n = 43), gastric foveolar type (n = 36), pyloric gland type (n = 11) and gastric combined type (n = 10). Half of the gastric foveolar type and the gastric combined type were located in the hilar region, but the other types were predominant at the periphery (P = 0.0004). Well-differentiated components were more often detected in the gastric combined type and the pyloric gland type (P = 0.0281). The gastric foveolar type was associated with a higher incidence of lymph node metastasis (P < 0.0001). The pyloric gland type was associated with better survival and the gastric foveolar type was associated with worse survival. The gastric mucin phenotype was an independent prognostic factor by multivariate survival analysis. CONCLUSION: The gastric foveolar type of ICC was more often associated with aggressive tumour development, whereas the pyloric gland type exhibited less aggressive behaviour.