Salmonella abortus ovis (Etude de 112 souches)

The bacteriological examination of 112 strains of Salmonella abortus ovis shows some particular properties of this serotype, and the existence of two different types according to their geographical source.     

Preparation of antigen for the counterimmunoelectrophoretic test for plasmacytosis in mink.

Counterimmunoelectrophoresis as a test method for making the diagnosis of plasmacytosis in mink demands the specific virus antigen. The method for preparation of the antigen according to Cho & Ingram (1972 a, b) with minor modifications is described in details, and results obtained at 62 antigen preparations are presented. In addition an ultrafiltration method is outlined which may be useful as a replacement for ultracentrifugation procedures used in the technique described by Cho & Ingram (1974).     

大肠杆菌新菌毛抗原的研究Ⅱ．菌毛抗原蛋白质特性测定

用保温法和裂解法可以有效提取Ｆ_(１９８７)新菌毛抗原蛋白质；该菌毛蛋白经区带电泳显示主、次两个组分，在０．０６ｍｏｌ／ＬｐＨ８．６巴比妥缓冲液电泳条件下，均向阳极泳动；免疫电泳显示两条沉淀线；其分子量为１９１００Ｄａ；等电点为３．０；由天门冬氨酸、苏氨酸、丝氨酸、谷氨酸、甘氨酸、丙氨酸、缬氨酸、异亮氨酸、亮氨酸、酪氨酸、苯丙氨酸、赖氨酸、组氨酸、精氨酸、脯氨酸、胱氨酸等１６种氨基酸组成。     

接种泰氏锥虫及其抗原使家兔和小鼠产生抗伊氏锥虫的交叉免疫力

用培养的泰氏锥虫制备的死、活两种虫体抗原,接种于家兔和小鼠,一定时间后用伊氏锥虫强毒株攻击,观察其血清抗体的变化及交叉免疫保护能力。试验表明,泰氏锥虫虫体抗原可刺激机体产生较高的体液抗体;免疫动物有一定的抵御伊氏锥虫攻击的能力,与对照组相比,免疫动物血液中虫体出现的时间较迟,最初的数量少,临床症状轻。死虫抗原组的交叉免疫保护能力较活虫抗原组强。     

片形吸虫分泌排泄抗原和虫体抗原的分析

用牛源肝片吸虫（南京）、牛源大片吸虫（广西）和羊源肝片吸虫（实验感染）制备可溶性虫体抗原（BA）和和分泌排泄抗原（ES），以SDS－PAGE电泳分析比较，结果显示，3株虫体可溶性虫体抗原至少有20条以上的主要蛋白条带，分子量集中于10－90KD之间，它们之间无显著差异，而3株分泌排泄抗原蛋白成分较简单，明显可分的条带不超过5条，分子量集中于10－30KD之间，且均拥有26－28KD的蛋白成分，提示该蛋白应为片形吸虫ES抗原的主要免疫成分。     

二氟沙星人工抗原的合成与鉴定

通过化学方法合成了二氟沙星人工免疫原和包被原；采用碳二亚胺法将半抗原二氟沙星与载体蛋白BSA连接制备人工免疫原；并采用氯甲酸异丁酯法将二氟沙星与载体蛋白OVA连接制备人工包被原，经FeCl3显色反应、紫外扫描分析和动物免疫试验证实人工抗原合成成功。这对抗二氟沙星单克隆抗体的制备具有重要意义。     

犬瘟热琼脂扩散试验方法的建立及初步应用

采用犬瘟热鸡胚成纤维细胞弱毒疫苗免疫绵羊制备琼脂扩散抗体，应用犬瘟热病貉肝脏（电镜检查“＋＋”以上）制备琼脂扩散抗原，建立了琼脂扩散试验方法，用于犬瘟热病死动物肝、脾脏器中病毒抗原成分的检出。检测送检病料１０份，与电镜检查结果比较，阳性符合率为８５．７％（６／７），阴性符合率为７５％（３／４），总体符合率为９０％（９／１０）。本方法特异、敏感，操作简便，易于推广应用。     

生育相关性抗原对精子受精的影响

生育相关性抗原对精子获能、受精具有重要作用,已经被认为是精子受精潜能的标志。该抗原降解精子-中性粒细胞结合物,使精子重获自由,提高受精精子比例。综述了FAA的生成、结构、化学性质及其与精子受精的相关性,以期为将其作为精液稀释剂的组分奠定基础。     

Detection of Oocyst‐Associated Toxoplasmosis in Swine from Southern Chile

Pork has been traditionally considered an important source of human Toxoplasma gondii infection. Pigs, as other meat‐producing animals, can become infected by the ingestion of oocysts that are shed in the environment by infected cats or by the consumption of cysts present in tissues of infected mammals, commonly small rodents. The objective of this study was to investigate the level of T. gondii infection in swine from southern Chile that can be associated with the ingestion of oocysts and therefore exposure to a contaminated environment. A total of 340 serum samples from swine were obtained from three commercial slaughterhouses located in the Araucania and Los Rios Regions from southern Chile. Study animals originated from local farms, mainly small commercial producers, and the meat is sold locally. Overall, 8.8% (30/340) of the samples showed T. gondii‐specific IgG antibodies. Of these sero‐positive animals, 80% (24/30) were also positive for antibodies specific against the oocyst stage of the parasite, indicating that animals had been infected recently by the ingestion of oocysts. The observed results suggest a high level of environmental contamination with oocysts on the farms of origin. In addition to the food safety problems associated with the consumption of meat from infected animals, the high level of environmental contamination on the farm represents a direct health risk for people living and/or working on these farms. Consequently, there is a need to develop on‐farm monitoring programmes and identify risk reduction strategies (food storage, water purification, rodent control and contact with cats) that are appropriate and cost‐effective for informal and outdoor type of farms.     

微小隐孢子虫三个基因主要抗原表位区的串联表达及其抗原性分析

应用多个抗原袁位预测软件对微小隐孢子虫CP15、P23和CP15/60三个子孢子表面抗原的氨基酸序列进行T细胞袁位预测及分析,从中选取了三个抗原表位富集的基因片段,利用重叠延伸PCR(gene splicing by overlapping extension PCR,SOE PCR)将该三个基因片段串联在一起,各基因片段之间以柔性氨基酸(GGGGS)碱基序列链接,得到的拼接片段命名为CpTm.将目的基因克隆到原核表达载体pET-28a(+)上,构建重组表达质粒pET-CpTm,并转化到大肠杆菌BL21(DE3)中进行诱导表达,将纯化的重组蛋白免疫BALB/c小鼠制备多克隆抗体.结果成功地构建了CpTm串联基因并在大肠杆菌中以可溶形式高效表达,质谱分析表明重组表达蛋白包含了上述三个抗原的氨基酸序列.Western blot分析显示该重组蛋白能被牛抗微小隐孢子虫阳性血清及隐孢子虫鼠基因型CP15、P23、CP15/60基因重组表达蛋白免疫兔血清识别,制备的抗血清能被重组蛋白特异性识别,表明表达的重组蛋白具有较好的反应原性和免疫原性,为多表位疫苗的研制奠定了基础.