Expression of canine interferon-gamma by a recombinant vaccinia virus and its antiviral effect

A recombinant vaccinia virus-expressing canine interferon (IFN)-gamma (vv/cIFN-gamma) was constructed. In rabbit kidney (RK13) and canine A72 cells infected with vv/cIFN-gamma, IFN activity was detected in the culture supernatants of both cell types. Canine IFN-gamma was also detected in both cell extracts by Western blot. The activity of the recombinant canine IFN-gamma in RK13 cells was higher than that in A72 cells. The vv/cIFN-gamma could not grow in A72 cells at a low multiplicity of infection, probably due to the antiviral activity of the canine IFN-gamma produced. Although exogenous IFN-gamma did not inhibit the growth of vaccinia virus, addition of anti-canine IFN-gamma serum recovered the growth of the vv/cIFN-gamma on A72 cells in a dose-dependent manner. These results suggest that the growth of vv/cIFN-gamma was inhibited by IFN-gamma produced in a paracrine and autocrine manner. In addition, the recombinant canine IFN-gamma inhibited the multiplication of canine herpesvirus, pseudorabies virus and canine adenovirus type 1 in Madin-Darby canine kidney cells. The antiviral effect of canine IFN-gamma was more effective than that of canine IFN-beta. From the present studies, we concluded the recombinant virus may be a useful suicide viral vector.     

免疫磁性海藻酸钠载药纳米微球的制备与评价

靶向治疗系统是目前研究的热点,用微乳化-离子交联方法制备包覆阿霉素的碳包铁/海藻酸钠复合纳米微球,以水溶性碳二亚胺为交联剂,将载药微球与单抗Hab18连接,制备出了免疫磁性药物纳米微球.对该免疫磁性微球的理化性能进行了表征,同时检测了免疫磁性微球中抗体的活性和免疫磁性微球与靶细胞的体外结合情况,结果表明,免疫磁性药物纳米微球平均粒径约为171.2nm,外观为球型,铁含量为14.6%,载药量为10.8%,且具有强磁响应性和长时间药物缓释效果.同时在体外该微球能够与靶细胞特异性结合.这种免疫磁性药物纳米微球有望成为一种优良的靶向肿瘤药物载体.     

Cloning of a truncated Babesia equi gene encoding an 82-kilodalton protein and its potential use in an enzyme-linked immunosorbent assay

To isolate Babesia equi genes encoding immunodominant proteins, a cDNA expression library prepared from B. equi mRNA was immunoscreened with B. equi-infected horse serum. Eighteen positive cDNA clones were obtained, and the clone that showed the strongest immunoreactivity, designated Be82, was further characterized. The Be82 gene consisted of 1,953 bp and contained a partial open reading frame lacking the 5'-terminal sequence. As shown by Western blot analyses, immune sera from mice intraperitoneally injected with the Be82 gene product recognized the 82- and 52-kDa proteins of B. equi but not those of Babesia caballi. The glutathione S-transferase fusion protein expressed in Escherichia coli that was purified and used as the antigen in the enzyme-linked immunosorbent assay reacted specifically with B. equi-infected horse sera. These results suggest that the Be82 gene product is a potential diagnostic antigen candidate in the detection of B. equi infection in horses that will be useful both in the performance of epidemiological studies and in the granting of quarantine passes.     

Construction of Canine Herpesvirus Vector Expressing Foreign Genes Using a lacZ-TK Gene Cassette as a Double Selectional Marker

An improved method for constructing canine herpesvirus (CHV) recombinants expressing foreign genes by using the lacZ-TK gene cassette as a double selectional marker was developed. A recombinant CHV carrying the lacZ-TK gene at a targeted gene locus was constructed and used as a parental virus for generating new recombinants. The parental virus formed blue plaques and was sensitive to TK-specific drugs, while newly generated recombinants, in which the lacZ-TK gene was replaced with the desired foreign gene, become both resistant to the TK-specific drugs and formed white plaques. Recombinants were isolated by using the combination of drug selection and color selection. This improved method allows construction of recombinant CHV with great ease, because the drug selection can enrich the frequency of recombinant CHV from 0.01–0.1% to 10–80%. This method was employed to construct a recombinant CHV that expressed rabies virus (RV) glycoprotein (G protein). This revised version was published online in July 2006 with corrections to the Cover Date.     

贵州与中国大陆其它地区空肠弯曲菌MLST特征的比较分析

目的 了解贵州省鸡源空肠弯曲菌的分子流行特征,阐明各地菌株间的亲缘关系和进化特征。方法 在贵州省随机抽取7个大型养鸡场,共采集210份鸡的新鲜粪便样本,分离培养出38株空肠弯曲菌,采用多位点序列分型对分离株的序列型及克隆复合体进行构成和聚类分析,与PubMLST数据库中来自国内的分离株分子特征进行比较。结果 贵州省38株鸡源空肠弯曲菌分为23种ST型和8个克隆复合体,其中9种是目前中国大陆地区已有的ST型,2个等位基因和8种序列型为新发现的。ST型构成比前四位分别是ST - 45、ST - 161、ST - 354、ST - 4 324,与数据库中已有的6株贵州来源菌株相比,不存在共同的ST型。优势克隆复合体（CC - 45、CC - 354、CC - 52）与数据库中鸡源分离株的前三位克隆复合体没有重叠。菌株遗传进化树显示,本研究中属于优势克隆复合体的18株菌与国内部分人源、猪源、野生鸟源、鹅源分离株有较近的遗传距离。结论 贵州省鸡源空肠弯曲菌具有高度遗传多样性,在一定程度上表现出地域流行特征。序列型与国内华东地区的分离株有较高的交叉性,部分分离株与国内人、野生鸟、鹅等来源分离株遗传距离近,应加强对不同地区、不同宿主来源空肠弯曲菌的动态监测。     

中国新疆地区宫颈人乳头瘤病毒感染情况的Meta分析

目的分析我国新疆地区女性宫颈人乳头瘤病毒(HPV)感染情况和基因型分布,为宫颈癌防治提供科学依据。方法计算机检索中国知网、万方数据库、中国生物医学文献数据库、Embase、Web of Science和PubMed数据库,搜集新疆地区女性宫颈HPV感染率和感染型别的文献,检索时限为上述数据库建库时间至2021年3月。由两位研究者根据纳入和排除标准独立筛选文献、提取资料和评价纳入研究后,进行Meta分析。结果最终纳入27篇文献,包含127073名研究对象。筛查人群HPV的感染率为12.4%(95%CI:10.8%~13.9%),高危型HPV感染率为10.0%(95%CI:8.7%~11.2%),低危型HPV感染率为1.9%(95%CI:0.9%~2.8%)。以不同地区作为分组因素进行亚组分析,乌鲁木齐的HPV感染率为16.0%(95%CI:12.4%~19.5%),和田的HPV感染率为10.1%(95%CI:8.9%~11.3%),喀什地区的HPV感染率为9.7%(95%CI:8.5%~10.9%)。排名前5的基因型分别为HPV16、HPV6、HPV11、HPV58、HPV51。结论新疆地区筛查人群HPV感染率略低于全国平均水平。不同地区的感染率有较大差异,乌鲁木齐的HPV感染率最高。HPV16是新疆地区最主要的感染型别。