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1.
依据NCBI中安氏隐孢子虫囊壁蛋白(COWP)编码基因设计特异性引物,提取安氏隐孢子虫长春株总RNA,RT-PCR扩增目的基因AF,构建重组原核表达载体pET28a-AF,通过大肠杆菌BL21诱导表达,产物经SDS-PAGE以及Western blotting鉴定。然后纯化重组蛋白,通过免疫BALB/c小鼠进行体液免疫和细胞免疫水平的检测。结果显示,重组原核表达质粒pET28a-AF构建成功,Western blotting显示重组蛋白约为18 000,可被安氏隐孢子虫免疫小鼠的多克隆抗体和HRP标记的抗组氨酸抗体识别。重组蛋白免疫BALB/c小鼠的抗体水平差异显著(P0.05),与对照组相比,CD4+的值差异极显著(P0.01),而CD8+的值差异显著(P0.05)。结果表明,成功克隆并表达了重组安氏隐孢子虫囊壁蛋白,纯化的重组蛋白具有一定的免疫原性。  相似文献   

2.
安氏隐孢子虫囊壁蛋白编码基因的克隆及原核表达   总被引:1,自引:0,他引:1  
为克隆和原核表达安氏隐孢子虫囊壁蛋白(COWP)的部分编码基因(AB),本研究根据COWP基因序列设计引物,RT-PCR扩增目的基因AB,从而构建重组原核表达质粒pET-AB。将重组质粒转化大肠杆菌BL21,IPTG诱导表达,经SDS-PAGE以及western blot鉴定。回收并纯化重组蛋白,免疫BALB/c小鼠,检测细胞免疫和体液免疫水平。SDS-PAGE和western blot分析显示,重组蛋白约为16 ku,可以被HRP标记的抗组氨酸抗体和安氏隐孢子虫免疫的小鼠血清识别。经重组蛋白免疫的BALB/c小鼠抗体水平以及CD4+和CD8+的值均差异显著(p0.05),表明获得的重组蛋白具有一定的免疫原性。  相似文献   

3.
将泰泽隐孢子虫(Cryptosporidium tyzzeri)CP15基因从pMD18-T-CP15重组质粒中切下,连接至pET-28a(+)原核表达载体,经酶切和测序鉴定正确后,转化到大肠埃希菌BL21(DE3)中进行诱导表达,表达产物进行SDS-PAGE和Western blot分析,并将纯化的重组蛋白免疫ICR小鼠制备多克隆抗体。结果显示,重组表达载体pET-28a-CP15在大肠杆菌中以可溶形式表达,表达蛋白分子量约为17 kDa。Western blot显示重组蛋白能被泰泽隐孢子虫感染小鼠血清所识别。ELISA结果显示重组蛋白免疫小鼠血清能和泰泽隐孢子虫卵囊可溶性抗原特异性反应,表明获得的重组蛋白具有较好的抗原性。  相似文献   

4.
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.  相似文献   

5.
应用多个服务器对微小隐孢子虫(Cryptosporidium parvum)候选疫苗抗原的氨基酸序列进行分析,预测可能存在的CD8+细胞毒性T细胞(CD8+cytotoxic T lymphocyte,CD8+CTL)表位。从6种常见的免疫效果较好的候选疫苗抗原基因中选出10个分值较高的表位基因串联在一起,形成一条多表位基因,进行人工合成,表位之间用柔性氨基酸GGGGS或GPGPG链接,命名为CpCTL10。将该多表位基因重组入高效融合表达载体pET-28a(+),获得重组质粒pET-28a(+)-CpCTL10,转化大肠杆菌BL21(DE3)进行诱导表达,表达产物进行SDS—PAGE、Western blot分析。结果显示,CpCTL10基因在大肠杆菌中主要以包涵体形式高效表达,表达的重组蛋白占菌体蛋白总量的55.3%,纯化的重组蛋白纯度达75.1%。Western blot分析显示表达产物能与感染隐孢子虫的鼠阳性血清发生特异性反应,表明表达的重组蛋白具有较好的抗原性,为多抗原多表位疫苗的研制打下某础.  相似文献   

6.
将猪繁殖与呼吸综合征病毒(PRRSV)ORF5基因疫苗(pcDNA—PRRSV—ORF5)以50、100、200μg 3个剂量肌注免疫BALB/c小鼠,以PBS和空载体质粒pcDNA为对照,采用流式细胞仪(FACS)、淋巴细胞增殖试验(MTT法)分别时小鼠外周血中CD4^+、CD8^+ T淋巴细胞数和淋巴细胞转化功能进行了检测。结果,3个剂量的pcDNA—PRRSV—ORF5接种小鼠后,其外周血都对ConA有明显的反应性。试验组与对照组比较差异极显著(P〈0.01)或显著(P〈0.05),CD4^+ T淋巴细胞数在免疫后7d高于对照组(P〈0.01),CD8^+ T淋巴细胞在免疫后28d高于对照组,大剂量基因疫苗免疫小鼠的细胞免疫应答高于中、小剂量。结果表明,pcDNA—PRRSV—ORF5免疫小鼠能够诱导机体产生良好的细胞免疫应答,并表现一定的剂量依赖性。  相似文献   

7.
猪繁殖与呼吸综合征病毒ORF5基因疫苗(pcDNA—PRRSV—ORF5)以不同免疫途径(基因枪和肌肉注射)免疫BALB/c小鼠,以PBS和空载质粒pcDNA3.1(+)为对照,采用流式细胞仪(FACS)、淋巴细胞增殖试验(MTT法)及间接ELISA试验分别对小鼠外周血中CD4^+、CD8^+T淋巴细胞数、T淋巴细胞的转化功能及小鼠血清中特异性PRRSV血清抗体IgG动态变化进行了检测。结果表明,pcDNA—PRRSV-ORF5基因疫苗接种小鼠后外周血对ConA有明显的反应性,试验组与对照组比较差异极显著(P〈0.01)或显著(P〈0.05),CD4^+T淋巴细胞数在免疫后7d高于对照组(P〈0.01),CD8^+T淋巴细胞在免疫后28d高于对照组,不同途径基因疫苗接种小鼠后均诱导小鼠产生PRRSV特异性IgG。在诱导细胞免疫方面,基因枪和肌肉注射各组间无明显差异;在诱导体液免疫方面,基因枪法优于肌肉注射。研究表明制备的pcDNA—PRRSV—ORF5基因疫苗免疫小鼠能够诱导其机体产生良好的体液和细胞免疫应答,基因枪法较肌肉注射更能诱导体液免疫应答的产生。  相似文献   

8.
为了研究新孢子虫NcSRS2和NcSAG1重组蛋白对动物的免疫效果,利用重组表达的NcSRS2和NcSAG1蛋白与弗氏佐剂混匀后免疫BALB/c小鼠,检测小鼠抗新孢子虫抗体水平和血清中IL-4和IFN-γ含量。结果表明,免疫后的BALB/c小鼠IgG、IgG2a和IFN-γ抗体表达水平升高,IgG1抗体和IL-4表达水平也升高,表明NcSRS2和NcSAG1重组蛋白可激发机体产生Th1型和Th2型免疫反应,且NcSRS2重组蛋白的免疫增强效果与NcSAG1重组蛋白免疫组的差异具有显著统计学意义(P0.05)。本研究结果为研制高效安全的抗新孢子虫的新型疫苗提供了参考。  相似文献   

9.
以微小隐孢子虫基因组DNA为模板,PCR扩增获得子孢子表面抗原CP15、P23和CP15/60基因。利用重叠延伸PCR(SOE PCR)将该3段基因片段串联在一起,各基因片段之间引入柔性氨基酸接头(GGGGS)编码基因。将串联基因克隆到原核表达载体pET-28a(+)上,构建重组表达载体,转化到大肠埃希菌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。结果表明,获得了CP15-P23-CP15/60融合基因,并在大肠埃希菌中高效表达,Western blot显示重组蛋白能被牛抗微小隐孢子虫阳性血清识别,制备的多克隆抗体能被重组蛋白特异性识别,表明获得的重组蛋白具有较好的抗原性。  相似文献   

10.
采用PCR技术扩增了微小隐孢子虫Cp23基因,将Cp23基因克隆至原核表达载体pET-28a(+)中,构建重组表达载体pET28a-Cp23。将其转化至宿主菌E.coli BL21(DE3)中,用IPTG诱导表达后进行SDS-PAGE和Western blot分析。SDS-PAGE结果表明,蛋白相对分子质量为25 000,目的蛋白高效表达,且为包涵体蛋白。Western blot结果表明,表达产物可被微小隐孢子虫阳性血清识别,具有良好的免疫反应原性。本研究为抗微小隐孢子虫疫苗和免疫学诊断方法的研制提供候选抗原。  相似文献   

11.
Cryptosporidium andersoni parasited in the abomasum has been demonstrated as a cause of reduction of milk production in dairy cow. In this study, a novel chimeric DNA vaccine pVAX1-AB was constructed and the efficacy against Cryptosporidium parvum was determined. BALB/c mice were divided into 3 groups and immunized with DNA vaccine expressing the oocyst wall protein, AB protein of C. andersoni, the recombinant plasmid containing the AB gene, respectively. After inoculation of 1 × 10(6) oocysts of C. parvum, the humoral and cellular immune responses were detected. Experimental results showed that the recombinant plasmid can induce corresponding specific antibody response, simultaneously influenced cellular immune responses, and provided greater protection rate (48.6%) than the other groups. These results indicated that chimeric DNA vaccine has a potential in Cryptosporidium vaccine development.  相似文献   

12.
In November 1997, Cryptosporidium andersoni, for the first time, was isolated from a Danish heifer. The isolate was characterised morphologically, molecularly, and furthermore inoculated into mice and one calf. Data on the distribution of cryptosporidia in the herd of origin were obtained at two separate visits in December 1997 and April 1998. C. andersoni was detected in 27 (19.0%) of 142 cattle examined at the first visit, whereas C. parvum was found in six (4.2%). At the following visit 42 (28.0%) of 150 cattle excreted C. andersoni, while 25 (16.7%) were positive for C. parvum. Oocysts of the Danish C. andersoni isolate were ovoid, 7.3(6.5-8.0) x 5.7(5.0-7.0) microm(2) (n=25), with smooth, colourless, single layer oocyst wall and distinct oocyst residuum. The length to width ratio was 1.27 (1.14-1.40, n=25). The identification was verified by sequencing of a 246bp fragment of the rDNA, which was identical to Cryptosporidium muris, the calf genotype (AF093496). The Danish C. andersoni isolate was not transmissible to mice, whereas oocysts were detected in the faeces of one experimentally infected calf from 25 days post-infection (DPI) and shed intermittently at low numbers until 165 DPI, the day of euthanasia. No macroscopic or microscopic changes that could be attributed to infection with C. andersoni were seen in the gastro-intestinal tract of the experimentally infected calf following necropsy and histological examination. This is to our knowledge the first report of C. andersoni in Scandinavia.  相似文献   

13.
Data of the prevalence, age-related and housing-dependence of naturally acquired cryptosporidiosis on 11 dairy and 11 beef farms in South Bohemia (Czech Republic) were collected. The farms were visited over four consecutive years (from 2002 to 2005). The prevalence of Cryptosporidium in pre-weaned (animals until second month of age) and post-weaned (animals from the third month of age) calves was determined. A total of 7001 faecal samples were collected, concentrated by Sheather's floatation method and stained by aniline-carbol-methyl violet. All samples were examined by light microscopy. Cryptosporidium parvum and C. andersoni oocysts were differentiated on morphological criteria. Of the 7021 specimens, 1814 (25.8%) were positive for Cryptosporidium oocysts; 561 samples (8%) for C. parvum and 1253 (17.8%) for C. andersoni. Pre-weaned dairy calves had higher infection levels of C. parvum than pre-weaned beef calves. The prevalence of C. parvum ranged from 1.4 to 56.5% on dairy farms. Only three cases of C. parvum oocysts shedding in pre-weaned calves on beef farms were found. Only one case of C. andersoni infection in pre-weaned calves was detected and no infections of C. parvum in post-weaned calves were found. The prevalence of C. andersoni reached 35.5% on dairy farms and 61.7% on beef farms. Calves that were on pasture all year long, had a lower probability of C. andersoni infection than those calves kept in a cowshed during the winter season.  相似文献   

14.
本研究旨在克隆微小隐孢子虫黏附相关蛋白基因CP21开放阅读框,构建其原核表达质粒,并对获得的融合蛋白进行鉴定。从含CP21基因的噬菌体中提取模板DNA,PCR扩增基因片段,构建pET-28a-CP21原核表达质粒,转化至埃希氏大肠杆菌BL21(DE3)中,IPTG诱导表达,表达产物经SDS-PAGE和Western blotting分析鉴定。用原核表达蛋白免疫小鼠,制备抗重组蛋白多抗,对蛋白进行定位。结果表明成功扩增出CP21基因,并构建原核表达质粒,转化至大肠杆菌中表达出相对分子质量为25 ku的融合蛋白,Western blotting证明表达的CP21融合蛋白能与抗C.parvum多克隆抗体产生特异性反应。免疫荧光结果表明:CP21基因在子孢子和卵囊期均表达,且表达产物位于子孢子表膜和卵囊壁表面。CP21是一种与侵入机制有关的黏附相关蛋白。研究结果为微小隐孢子虫的免疫学诊断及疫苗研制奠定了基础。  相似文献   

15.
The effect of heat treatment was examined against oocysts of Cryptosporidium parvum, Cryptosporidium muris and chicken Cryptosporidium sp. isolated in Japan. The oocysts of these species were exposed at 50, 55, 60 and 70 degrees C for 5, 15, 30 and 60 sec in water bath, respectively. To determine the infectivity of heated oocysts, the nice and chickens were inoculated with the treated oocysts and the oocyst output in the feces after inoculation was examined. In C. parvum and chicken Cryptosporidium sp., the oocysts were not detected from mice or chickens which were received oocysts heated at 55 degrees C for 30 sec, 60 degrees C for 15 sec and 70 degrees C for 5 sec. In C. muris, the oocysts were not detected from mice which were received oocysts heated at 55 degrees C for 15 sec, 60 degrees C for 15 sec and 70 degrees C for 5 sec. Consequently, it was clarified that the infectivity of Cryptosporidium oocysts to mice and chickens was lost by heating at 55 degrees C for 30 sec, 60 degrees C for 15 sec and 70 degrees C for 5 sec.  相似文献   

16.
安氏隐孢子虫PCR检测方法的建立   总被引:1,自引:1,他引:1  
经BLAST检索,以HSP70基因设计一对引物(5'-CAATCGAATTGGATTCTTTGTC-3'和5'-CACCTTCAAAT-ACTTGAATAAGT-3')对奶牛安氏隐孢子虫进行了PCR试验.结果显示所建立的PCR检测方法只能特异扩增隐孢子虫GD株DNA,而对照样本如微小隐孢子虫、弓形虫、圆孢子虫、纤毛虫、肝片吸虫、血矛线虫、莫尼茨绦虫、牛粪便以及大肠杆菌均为阴性;通过对6个浓度梯度的虫体DNA进行PCR反应,结果表明当样本中含有445个隐孢子虫卵囊的DNA时,即可扩增产生清晰可辩的条带.测得该序列长度为494bp,序列分析为牛型C.andersoni.表明该引物能特异扩增C.andersoni,敏感性较高,适合于奶牛安氏隐孢子虫的检测.  相似文献   

17.
试验旨在通过大肠杆菌表达系统表达鼠源重组CD40L蛋白,探讨其对河豚毒素(tetrodotoxin,TTX)人工完全抗原在免疫BALB/c小鼠过程中的免疫增强作用。用Trizol试剂提取BALB/c小鼠脾脏总RNA并反转录成cDNA,根据CD40L CDS区设计引物,PCR扩增目的基因,构建pGEX4T-1重组载体,进行原核表达,并纯化重组CD40L蛋白;根据曼尼希反应原理,用甲醛法制备TTX免疫原TTX-BSA和检测原TTX-OVA;以人工重组蛋白CD40L佐剂组为试验组,弗氏佐剂组作为对照组,免疫BALB/c小鼠,用ELISA方法结合SPSS 19.0软件分析各组免疫效果,探讨重组CD40L蛋白在TTX-BSA免疫过程中对免疫效果的影响。结果显示,本试验成功扩增了783 bp的CD40L目的基因,原核表达并纯化了融合GST标签的55 ku鼠源CD40L重组蛋白;与人工制备的TTX-BSA协同免疫小鼠试验结果显示,在免疫初期与弗氏佐剂相比,CD40L具有极显著的免疫增强效果(P<0.01)。综上所述,重组蛋白CD40L与TTX-BSA完全抗原协同免疫小鼠,在免疫初期CD40L具有增强机体对半抗原的应答强度的作用,为进一步开发适于小分子半抗原抗体高效制备的免疫增强佐剂奠定基础。  相似文献   

18.
An experimental study was carried out in neonatal goat kids to examine the infectivity of Cryptosporidium oocysts, pattern of oocyst shedding and morphological changes in the intestine during the infection. Cryptosporidium oocysts isolated from adult asymptomatic goats, and identified as C. parvum by polymerase chain reaction (PCR) were used in this study. Of three 4-day-old goat kids, two were orally infected with C. parvum oocysts (10(5) oocysts in 10 ml PBS/kid). One goat kid given 10 ml PBS only by the oral route served as a control. Cryptosporidium oocysts were detected in the faeces of one infected kid on day 3 post-inoculation (pi) whereas in the other 6 days pi. The faecal oocyst counts gradually increased and the peak counts in the two kids were 2 x 10(6)g(-1) (on day 12 pi) and 3.2 x 10(6)g(-1) (on day 14 pi). The increase in faecal oocyst output coincided with diarrhoea in an infected kid from days 10-17 pi. Although the oocyst excretion declined gradually after the peak, both infected kids excreted oocysts until euthanized on days 20 and 22 pi. Light and scanning electron microscopic investigations of the ileum revealed the endogenous stages on the brush border of the enterocytes, infiltration of neutrophils and mononuclear cells into the lamina propria, atrophy, stunting and fusion of villi. For purposes of comparison, goat Cryptosporidium oocysts were inoculated orally (10(3) oocysts/mouse) to eight, 1-week-old mice. All experimental mice excreted oocysts from day 3 pi, and four infected mice continued to excrete oocysts up to day 42 pi. The experimental infection described in goat kids resembled the natural disease in terms of oocyst excretion, clinical signs and intestinal pathology. The ability of oocysts excreted by asymptomatic goats, to infect goat kids and mice is likely to have a major impact on the epidemiology of cryptosporidiosis in livestock and man.  相似文献   

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