Conjugation of DNA fragments to protein carriers by glutaraldehyde: immunogenicity of oligonucleotide-hemocyanin conjugates

The practical realization of the concept of specific immunotherapy for systemic lupus erythematosus (SLE) has been hampered, thus far, by an inability to link DNA fragments to carrier protein. In this paper, a novel technique is described, in which glutaraldehyde is the linking agent. A 2-stage method was used to link oligonucleotides to a soluble protein carrier, such as keyhole limpet hemocyanin (KLH) or human gamma globulin (HGG), whereas a 1-stage technique was sufficient to link oligonucleotides to sheep red cells. Both the ultraviolet absorbance spectrum and diphenylamine assay demonstrated that oligonucleotides were coupled to soluble protein. The conjugate of oligonucleotide to protein carrier appears to be recognized by anti-DNA antibody since oligonucleotide linked to either KLH or HGG inhibited the binding of anti-DNA antibody in vitro, and oligonucleotide-coupled sheep cells are agglutinating by seropositve sera from lupus patients. In addition, oligonucleotide-KLH raised hemagglutinating antibody to denatured DNA in C57BL/6, DBA/2 or NZB mice, as well as IgG antibody as detected by SPRIA in C57BL/6 and DBA/2 mice. The significance of this new method for the development of an antigen specific therapy of SLE is discussed.     

PDGF-B链基因三链形成寡核苷酸对C6胶质瘤细胞增殖和细胞周期的影响

目的观察PDGF-B链基因三链形成寡核苷酸(triplex-forming oligonucleotide,TFO)对C6胶质瘤细胞增殖和细胞周期的影响.方法应用免疫荧光流式细胞技术观察PDGF-B链基因TFO对C6胶质瘤细胞PDGF-B、PCNA表达的影响.应用流式细胞技术观察PDGF-B链基因TFO对C6胶质瘤细胞细胞周期的影响.结果 PDGF-B链基因TFO对C6胶质瘤细胞PDGF-B链基因、PCNA的表达有明显抑制作用,而且抑制作用存在浓度依赖性.PDGF-B链基因TFO能使C6胶质瘤细胞S期的百分率明显降低,阻止细胞由静止期(G0-G1期)进入(S期).结论 PDGF-B链基因TFO能够抑制C6胶质瘤细胞PDGF-B链基因的表达,阻碍细胞进入S期,降低细胞增殖能力.     

异鸟苷掺入的富鸟嘌呤寡核苷酸的合成

目的改进异鸟苷单体的合成路线,合成异鸟苷掺入的富鸟嘌呤的寡核苷酸.方法以6-O-苄基鸟嘌呤为原料,经环氧开环、催化氢化、水解还原制备异鸟苷,经多步反应后得到异鸟苷亚磷酰化产物,采用固相合成方法合成异鸟苷掺入的富含鸟嘌呤的寡核苷酸.结果与结论经环氧开环能够区域选择性地得到N9取代的单一产物,收率提高到40%,并成功地合成了异鸟苷掺入的富含嘌呤十六聚寡核苷酸.本合成路线具有区域选择性强、路线简单、易操作、收率高等优点.     

反向点杂交快速检测流感嗜血杆菌

目的　研究以分子杂交为基础的流感嗜血杆菌 (Hi)的快速检测方法。方法　将Hi探针固定在尼龙膜上 ;用标记有地高辛的细菌通用引物聚合酶链反应 (PCR)扩增不同细菌DNA ,产物分别与点有探针的膜条杂交。结果　 8种细菌均扩增出 4 6 8bp目的带 ,而人白细胞及轮状病毒DNA扩增均阴性。 6株Hi杂交阳性 ,7株其他临床常见菌杂交结果阴性。结论　反向点杂交法简便、快速、准确 ,是检测Hi的一种理想方法。     

转录因子NF-KB对血管成形术后血管狭窄和新生内膜形成的影响

目的探讨核转录因子NF-KB的反义和诱骗性寡核苷酸对大鼠颈动脉球囊损伤后血管增殖反应及相应细胞因子、细胞外信号调节激酶的影响。方法SD大鼠随机分为7组．每组分为6个时相点（6h，1，3，5，7，14d），每个时相点3只大鼠。制作血管球囊损伤模型.相应时间点处死动物，使用病理形态学、逆转录聚合酶链反应、免疫组化、Western blot等方法测定血管病理形态改变、单核细胞趋化因子（Monocytes chemotactic protein-1，MCP-1）的mRNA和蛋白质表达、NF-KB p65和细胞外信号调节激酶（Extra-cellular signal regulated kinase，ERK2）的蛋白质含量。结果 模型组、正义组、Scramble组血管内膜／中膜在d 5增加，14d达到高峰。反义组、诱骗组、反义组＋诱骗组干预后，血管内膜／中膜明显减小（P〈0．05），反义组＋诱骗组较反义组、诱骗组治疗效果不明显。MCP-1 mRNA表达在血管损伤后6h即可检测到，3、5、7d后持续表达增加，14d后表达降低，免疫组化显示MCP-1蛋白质表达在6个时相点均为阳性染色，14d达到高峰；反义组、诱骗组、反义组＋诱骗组治疗后，与模型组、正义组、Scramble组相比，MCP-1 mRNA表达和蛋白合成在各时相点均降低（P〈0．05）．Western blot检测核蛋白抽提物显示核因子NF-KB p65在血管损伤后6h有一定蛋白表达，1d后蛋白表达明显增加，至7d达高峰，14d后蛋白表达略降低。ERK2在血管损伤后1d蛋白表达开始增加，d7达到峰值．14d后与d7相比尤明显差异。反义组、诱骗组、反义组＋诱骗组干预后，各时相点蛋白质表达均较模型组、正义组、Scramble组减弱（P〈0．05）。结论转录因子NF-KB调控MCP-1、ERK2基因表达和蛋白质合成；球囊损伤后血管壁细胞增殖在不同时相点有动态变化；脂质体介导局部转染反义、诱骗性寡核苷酸可抑制NF-KB激活对下游基因的调控，两者联合作用效果较单独应用未表现出更明显的作用。     

反义寡核苷酸抑制survivin基因表达及肝癌细胞生长的研究

目的:采用反义寡核苷酸抑制肝癌细胞中survivin基因的表达,研究其对肝癌细胞生长的作用.方法:采用脂质体介导survivin反义寡核苷酸转染人肝癌细胞株SMMC-7721细胞,Western blot及原位杂交方法检测survivin蛋白及mRNA表达,流式细胞仪检测凋亡细胞比率,检测转染前后细胞贴壁率变化,并绘制细胞生长曲线.结果:survivin反义寡核苷酸转染后,肝癌细胞survivin蛋白及mRNA表达均显著降低,细胞贴壁率显著降低,细胞增殖活性明显受抑,细胞凋亡率显著增加.结论:survivin反义寡核苷酸转染可以有效降低细胞内survivin基因的表达,诱导细胞发生凋亡,抑制肝癌细胞生长.     

Increased HLA-A*11 in Chinese children with steroid-responsive nephrotic syndrome

Human leukocyte antigen (HLA) associations have been frequently reported in childhood steroid-responsive nephrotic syndrome (SRNS) in other populations. The aim of this study was to characterize the immunogenetic background of Singaporean Chinese patients with childhood SRNS. We determined the HLA class I (HLA-A* and HLA-B*) as well as class II (HLA-DRB1*, HLA-DQB1*) gene polymorphisms using the polymerase chain reaction-sequence specific oligonucleotide (PCR-SSO) technique, in patients with SRNS (n=64) and normal controls (n=236 for HLA-A*, n=80 for HLA-B*, HLA-DRB1* and HLA-DQB1*). The frequency of HLA-A*11 allele was significantly higher in the SRNS patients compared to controls (78.1% vs 54.2%, respectively; relative risk, RR=3.01, Pc=0.011). However, there was no significant difference in the allele frequencies of HLA-B*, HLA-DRB1* and HLA-DQB1* between the SRNS patients and controls, unlike that in previous studies. Our data suggest that the immunogenetic background of Singaporean Chinese with childhood SRNS was different from that in other populations. As HLA-A*11 has been strongly associated with other autoimmune diseases, it is conceivable that the HLA-A*11-specific motif may play a role in the development of the abnormal T-cell-mediated immune response that may be responsible for triggering the proteinuria seen in SRNS. Received: 24 April 2001 / Revised: 14 November 2001 / Accepted: 18 November 2001     

microRNA-29a在结直肠癌组织中的表达及意义

目的 探讨microRNA-29a（miR-29a）在结直肠癌组织中的表达,以及miR-29a反义寡核苷酸对结直肠癌细胞增殖和侵袭的影响。方法 选取行手术治疗的初诊结直肠癌患者195例,利用实时荧光定量聚合酶链反应检测结直肠癌和癌旁组织中miR-29a表达,培养人结直肠癌LoVo细胞,随机分为ASO-miR-29a组、ASO-对照序列组和空白对照组,检测各组细胞中miR-29a表达,MTT法检测各组细胞增殖能力,Transwell小室检测各组细胞迁移和侵袭能力。结果 结直肠癌组织miR-29a相对表达量为（1.93±0.19）,癌旁组织为（1.26±0.12）,两者比较差异有统计学意义（P?<0.05）;结直肠癌组织中miR-29a相对表达量与TNM分期和淋巴结转移有关（P?<0.05）,多元线性回归分析结果显示,TNM分期和淋巴结转移是影响结直肠癌组织中miR-29a表达的因素（P?<0.05）;ASO-miR-29a组细胞中miR-29a相对表达量低于ASO-对照序列组和空白对照组（P?<0.05）;MTT实验结果显示,ASO-miR-29a组与ASO-对照序列组和空白对照组相比吸光度值降低（P?<0.05）;与ASO-对照序列组和空白对照组比较,ASO-miR-29a 组迁移细胞数和侵袭细胞数均减少（P?<0.05）。结论 miR-29a在结直肠癌组织中呈高表达,参与结直肠癌发生、进展过程,特异性抑制结直肠癌细胞中miR-29a表达可减少细胞增殖,抑制细胞迁移和侵袭能力。     

Inhaled ENaC antisense oligonucleotide ameliorates cystic fibrosis-like lung disease in mice

Background

Epithelial sodium channel (ENaC, Scnn1) hyperactivity in the lung leads to airway surface dehydration and mucus accumulation in cystic fibrosis (CF) patients and in mice with CF-like lung disease.

灭活Chk1/2基因增强H4细胞放疗后凋亡敏感性

o照射可引起H4细胞G2/M期阻滞,以10 Gy 60C0照射12h G2/M期阻滞最明显;单独反义封闭Chk1或Chk2基因可增强放疗后凋亡敏感性100%～200%,而同时反义封闭Chk1和Chk2基因具有协同作用,增强放疗后凋亡敏感性300%,其机制是通过解除G2/M期阻滞实现的.结论 放疗可激活细胞周期检测点信号传导通路导致放疗抵抗,而阻断该信号通路的关键激酶Chk1和Chk2可显著增强放疗后凋亡敏感性.