雄黄纳米微粒在细胞水平上抑制呼吸道合胞病毒复制的初步研究

建立呼吸道合胞病毒A型(RSV-A型)感染Hep-2细胞模型,通过预防、治疗及直接灭活三种不同给药方式,观察中药雄黄对RSV-A型感染Hep-2细胞病变(CPE)的抑制作用。用高能球磨机研磨双蒸水水飞处理制备雄黄纳米微粒,应用砷钼蓝染色法测定雄黄纳米微粒浓度并在Nano Series粒度测定仪上测定其粒度。以MTT法计算药物的半数中毒剂量(TC50)。通过三种不同给药方式即预防给药、治疗给药及直接灭活给药方式进行体外实验,以利巴韦林为阳性对照药,观察雄黄纳米微粒对RSV-A型感染Hep-2细胞病变所起的作用,并对药物的量效关系进行分析。雄黄纳米微粒TC50值为0.649μg/mL。预防、治疗及直接灭活给药方式均可减轻RSV-A感染Hep-2细胞的CPE程度,其抑制RSV-A型感染Hep-2细胞病变的半数有效浓度(IC50)分别为0.20μg/mL、0.13μg/mL、0.16μg/mL,治疗指数(TI)分别为3.18、4.99和4.11,雄黄纳米微粒对RSV-A型感染Hep-2细胞病变的抑制作用存在着明显的量效关系。雄黄纳米微粒按预防、治疗及直接灭活给药方式给药时,其中治疗给药方式更有利于减轻RSV-A感染Hep-2细胞引起的病变。     

人呼吸道合胞病毒M蛋白非复制型重组腺病毒的构建和鉴定

人呼吸道合胞病毒（human respiratory syncytial virus, RSV)基质蛋白（matrix protein,M）在RSV形态发生上具有重要作用,因含有CTL抗原表位,在疫苗研究上具有一定意义。为此,应用RT-PCR 方法从感染RSV的HEp-2 细胞中扩增获得M蛋白基因,构建了含M基因的非复制型重组腺病毒并进行表达和鉴定。基因序列分析显示RSV M基因仅有一处碱基发生错义突变。非复制型重组腺病毒DNA分子FGAd/RSVM转染293细胞,观察到细胞出现CPE,RT-PCR发现M基因有转录,Western blotting及间接免疫荧光分析检测到M蛋白。成功克隆A亚型RSV Long株M基因,并获得一株可表达A亚型RSV M蛋白的非复制型重组腺病毒FGAd/RSVM,可用于体内研究观察其免疫效果及免疫保护作用。     

Altered Growth Characteristics of Recombinant Respiratory Syncytial Viruses Which Do Not Produce NS2 Protein

The second gene in the 3′-to-5′ gene order in respiratory syncytial virus (RSV) encodes the nonstructural protein NS2, for which there is no assigned function. To study the function of NS2, we have used a recently developed reverse genetics system to ablate expression of NS2 in recombinant RSV. A full-length cDNA copy of the antigenome of RSV A2 strain under the control of a T7 promoter was modified by introduction of tandem termination codons within the NS2 open reading frame (NS2stop) or by deletion of the entire NS2 gene (ΔNS2). The NS2 knockout antigenomic cDNAs were cotransfected with plasmids encoding the N, P, L, and M2-1 proteins of RSV, each controlled by the T7 promoter, into cells infected with a vaccinia virus recombinant expressing T7 RNA polymerase. Recombinant NS2stop and ΔNS2 RSVs were recovered and characterized. Both types of NS2 knockout virus displayed pinpoint plaque morphology and grew more slowly than wild-type RSV. The expression of monocistronic mRNAs for the five genes examined (NS1, NS2, N, F, and L) was unchanged in cells infected with either type of NS2 knockout virus, except that no NS2 mRNA was detected with the ΔNS2 virus. Synthesis of readthrough mRNAs was affected only for the ΔNS2 virus, where the NS1-NS2, NS2-N, and NS1-NS2-N mRNAs were replaced with the predicted novel NS1-N mRNA. Upon passage, the NS2stop virus stock rapidly developed revertants which expressed NS2 protein and grew with similar plaque morphology and kinetics wild-type RSV. Sequence analysis confirmed that the termination codons had reverted to sense, albeit not the wild-type assignments, and provided evidence consistent with biased hypermutation. No revertants were recovered from recombinant ΔNS2 RSV. These results show that the NS2 protein is not essential for RSV replication, although its presence greatly improves virus growth in cell culture. The attenuated phenotype of these mutant viruses, coupled with the expected genetic stability associated with gene deletions, suggests that the ΔNS2 RSV is a candidate for vaccine development.     

菊花总黄酮对RSV感染A549细胞趋化因子的影响

目的:探讨菊花总黄酮对小儿RSV感染A549细胞诱导RANTES及MCP-1释放作用影响。方法:实验分为细胞对照组,病毒对照组,菊花总黄酮组和病毒唑组。在Hep-2细胞和A549细胞分别加入菊花总黄酮和病毒唑的含药维持液,测定上述两种药物的最大无毒浓度;RSV病毒感染Hep-2细胞,观察药物对RSV的病毒抑制作用;RSV感染A549细胞,ELISA法测细胞趋化因子RANTES及MCP-1含量。结果:菊花总黄酮50%有效率优于病毒唑组,差异有统计学意义(P0.05);RANTES及MCP-1释放抑制作用比较中,菊花总黄酮组RANTES、MCP-1明显降低,优于病毒唑组,差异有统计学意义(P0.05)。结论:菊花总黄酮能够抑制RSV病毒活性,明显降低A549细胞释放RANTES、MCP-1,缓解患儿的呼吸道症状,对临床具有指导意义,值得临床推广。     

Knockdown of DGCR5 enhances the radiosensitivity of human laryngeal carcinoma cells via inducing miR-195

Long noncoding RNAs (lncRNAs) exert critical roles in the development of various cancers, including human laryngeal cancer. Radioresistance contributes to the predominant causes of laryngeal cancer recurrence after radiotherapy. The aim of our study was to investigate the association of dysregulated lncRNA and radiation resistance in human larynx squamous carcinoma. Here, we investigated the biological roles of lncRNA DiGeorge syndrome critical region gene 5 (DGCR5) in radioresistance of human laryngeal cancer. Two human larynx squamous carcinoma cell lines (Hep-2 and Hep-2R), with different radiosensitivities in vitro were used in the present study. We observed that DGCR5 was significantly upregulated in Hep-2R cells. Inhibition of DGCR5 by LV-shDGCR5 transfection restrained Hep-2R cell proliferation and sensitized cells to radiation. Reversely, overexpression of DGCR5 exhibited an opposite phenomenon in vitro. In addition, microRNA (miR)-195 was predicted as a direct downstream target of DGCR5. Dual-luciferase reporter and RNA immunoprecipitation assays verified the direct interaction between them. Meanwhile, miR-195 was observed to be reduced in Hep-2R cells and miR-195 mimics repressed Hep-2 cell growth. Moreover, radiosensitivity of Hep-2R cells was greatly enhanced by overexpression of miR-195, which could be reversed by upregulation of DGCR5. Finally, in vivo experiments were used to validate that knockdown of DGCR5 suppressed laryngeal carcinoma via targeting miR-195. In conclusion, we indicated that DGCR5 could contribute to the radioresistance of human laryngeal carcinoma cells via sponging miR-195.     

呼吸道合胞病毒IgG酶联检测试剂盒的研制

为了研制检测呼吸道合胞病毒IgG的酶联检测试剂盒,以呼吸道合胞病毒Long株病毒液作为包被抗原,HRP标记羊抗人IgG作为信号抗体,制备ELISA抗体检测试剂盒。结果表明建立的RSV酶联检测试剂盒敏感性与进口试剂盒接近,特异性达 95. 24%,重复性好,批内变异系数为 6. 35%,试剂盒置于 37℃ 0天与 7天检测结果无显著差异。成功制备了RSVIgG酶联检测试剂盒。