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71.
制备哈氏弧菌SpGY020601外膜蛋白复合物(OMPC)和溶藻弧菌EpGS021001脂多糖(LPS)偶联疫苗,设置偶联疫苗组、偶联疫苗 ISA763佐剂组、偶联疫苗 β-葡聚糖佐剂(DEAE)组以及生理盐水对照组,并以相同程序免疫卵型鲳鲹。溶菌酶活性检测、微量凝集反应试验结果显示:各疫苗组血清中的溶菌酶含量无显著差异(P>0.05),但均远高于生理盐水对照组(P<0.05);ISA763佐剂组抗哈氏弧菌SpGY020601抗体滴度较其他组出现的早,抗溶藻弧菌EpGS021001抗体滴度较其他组持续时间长;β-葡聚糖佐剂组次之,其次是无佐剂组,对照组始终未检测到抗体。各组分为腹腔注射攻毒与浸泡攻毒,对EpGS021001的攻击,ISA763佐剂组相对保护率分别为90%和70%,高于β-葡聚糖佐剂组的85%和55%,以及无佐剂组的80%和55%;对SpGY020601的攻击,ISA763佐剂组相对保护率分别为95%和80%,高于或相当于β-葡聚糖佐剂组的95%和75%,以及无佐剂组的90%和75%。 相似文献
72.
为了研究无乳链球菌Sip-GAPDH嵌合核酸疫苗对罗非鱼链球菌病的免疫保护作用,本研究通过PCR和重叠延伸拼接技术(SOEing)获得融合基因Sip-GAPDH,连接至真核表达载体pcDNA3.1(+)制备DNA疫苗,通过背鳍肌肉注射方式免疫吉富罗非鱼,免疫后第7、28天取样,采用PCR及RT-PCR方法检测pcDNA-Sip-GAPDH在各个组织(包括肌肉、脑、头肾、脾脏、鳃和肝脏)中的表达情况。采用ELISA、Real-time PCR法和体外攻毒法分别分析各实验组不同时间血清抗体效价、免疫基因(IgM、IL-1β和CD8)表达变化规律和相对保护率,研究该嵌合性疫苗对吉富罗非鱼的保护效果。结果显示,实验组在免疫接种第7和第28天时,注射点周围的肌肉、脑、头肾、脾脏、鳃和肝脏均能检测到嵌合性质粒,实验组罗非鱼血清抗体效价均高于对照组并于21 d时达到峰值(1∶4 096);qPCR数据表明,实验组鱼体胸腺、头肾和脾脏的IgM、IL-1β和CD8基因的mRNA表达量均出现了上调,并且在胸腺、头肾和脾脏中的表达量分别在免疫后第12和第48 h达到峰值;免疫后42 d进行人工攻毒后计算免疫保护率为93.3%。以上研究结果表明,本研究构建的无乳链球菌Sip-GAPDH嵌合核酸疫苗在罗非鱼链球菌病防治中具有潜在的应用价值。 相似文献
73.
Live, attenuated Vibrio anguillarum strains can serve as vectors for the delivery of heterologous antigens for development of multivalent recombinant vaccines. Based on the outer membrane anchoring elements of V. anguillarum , we have previously constructed several efficient surface display systems Lpp-Omporf1, Lpp-OmpU, Lpp-Omp26La, Wza-Omporf1, Wza-OmpU and Wza-Omp26La. In this study, with these constructed surface display systems, a putative antigen protein EseB from pathogenic Edwardsiella tarda was successfully expressed on the surface of an attenuated V. anguillarum strain to get multivalent vaccine candidates. Further immune protection evaluation in zebra fish ( Danio rerio ) demonstrated that the V. anguillarum EseB-display strain AV/pW-26La-B could trigger full protection against V. anguillarum infection and early protection against E. tarda infection in the immunized fish. These results suggest that surface display of heterologous protective antigens in attenuated V. anguillarum could be used as a tool to develop potential V. anguillarum vector vaccine. 相似文献
74.
蜂胶佐剂对异育银鲫嗜水气单胞菌灭活疫苗的免疫增强试验 总被引:2,自引:0,他引:2
本文就蜂胶佐剂对鱼类细菌性疫苗的免疫增强作用进行了首次评价。试验以异育银鲫嗜水气单胞菌灭活疫苗为对象,比较了蜂胶佐剂、铝胶佐剂和无佐剂三种疫苗对银鲫的免疫效果。经抗体监测表明,免疫接种后第2周,蜂胶佐剂组银鲫已检测到血清抗体,随后抗体效价迅速上升,第4周达到峰值2^5:铝胶佐剂组和无佐剂组第3周检测到抗体.铝胶佐剂组第5周达到峰值2^5,无佐剂组第4周达到峰值2^4。银鲫免疫后第5周进行攻毒保护试验,发现蜂胶佐剂组、铝胶佐剂组和无佐剂组的免疫保护率分别为77.3%.65.0%和56.3%。试验结果表明,蜂胶佐剂能有效增强异育银鲫细菌性灭活疫苗的免疫保护力。 相似文献
75.
山莨菪碱提高嗜水气单胞菌灭活疫苗浸泡免疫鲫的效果 总被引:1,自引:3,他引:1
为研究山莨菪碱作为佐剂在细菌灭活疫苗浸泡免疫中的作用,将山莨菪碱和嗜水气单胞菌全菌灭活疫苗联合浸泡免疫异育银鲫,首次浸泡免疫7d后加强免疫1次.通过实时荧光定量PCR检测第2、4、7、11、14和21天脾脏中IgM、IL-1β、C3、C-凝集素以及溶菌酶的mRNA表达量,并在第21天进行同源菌株活菌攻击实验.结果显示,山莨菪碱组第4天IgM和IL-1 β的表达量达到最高值,分别为28.3和332.7;而无佐剂疫苗组第11天IgM和IL-1β达到最高值,分别为56.1和791.8.山莨菪碱组的补体C3、C-凝集素以及溶菌酶的表达量都显著高于无佐剂组和对照组,且表达持续时间长.活菌攻击实验表明山莨菪碱组的相对免疫保护率可达80.0%,显著高于无佐剂组的56.0%.结果表明,山莨菪碱与嗜水气单胞菌灭活疫苗共同浸泡免疫银鲫,可以增强脾脏中IgM、IL-1β、C3、C-凝集素以及溶菌酶基因表达,提高银鲫相对免疫保护率. 相似文献
76.
77.
Mary R. Arkoosh Joseph P. Dietrich Mary Beth Rew Wendy Olson Graham Young Frederick W. Goetz 《Aquaculture Research》2018,49(1):205-216
Wild sablefish, Anoplopoma fimbria, are a valuable commercial species whose populations are declining. Fortunately, sablefish are excellent species for commercial aquaculture. Sablefish raised under high‐density conditions in the marine environment require the use of efficacious vaccines to control disease. Sablefish impacted by disease in net pens may have poor flesh quality and high mortality during grow‐out. As a result, disease can cause financial hardship for sablefish aquaculture operators. The efficacy of a multivalent vaccine preparation for sablefish, administered either by intraperitoneal (i.p.) injection or by immersion, against atypical and typical Aeromonas salmonicida, the causative agents of atypical and typical furunculosis, respectively, was examined. A. salmonicida can affect sablefish at any age and size. Consequently, an efficacious vaccine that can be appropriately and optimally administered to all life stages is desirable. Sablefish vaccinated by immersion at ~1.5 or ~4.5 g with a whole‐cell multivalent vaccine were not protected against either typical or atypical A. salmonicida. Factors that may have contributed to the ineffectiveness of the immersion vaccine are discussed. By contrast, the relative per cent survival (RPS) or potency of the whole‐cell multivalent vaccine injected i.p. in juvenile sablefish at ~50 g against typical and atypical A. salmonicida was 94.3% and 81.7% respectively. The high RPS values indicated that the vaccine successfully initiated an immune response in sablefish upon a second encounter with the pathogen. 相似文献
78.
79.
《Communications in Soil Science and Plant Analysis》2012,43(1-2):368-376
Assessing the nutrient status of low-input, low-fertility desert soils poses some unique challenges. Commonly used soil analysis procedures and resin capsules generally assess nutrient status of fertile agricultural soils. Ion-exchange resin capsules (Unibest Company, Bozeman, Mont.) provide a viable alternative. A study was conducted to determine effectiveness of resin capsules to extract low levels of nutrients applied to native soils. Loamy sand and sandy clay loam desert soils from Utah were treated with combinations of four rates of nitrogen (N) as ammonium nitrate (34–0–0), three rates of phosphorus (P) as phosphoric acid (0–72–0), and two rates of iron sulfate (FeSO4·7H2O) and zinc sulfate (ZnSO4·7H2O) (include an untreated control). Each soil treatment was implanted with a resin capsule placed into either 250 or 1000 cm3 of soil after addition of water equivalent to 50% field capacity and incubated for either 60 or 120 days at 25 °C. After the appropriate incubation time, capsules were washed and extracted using 2 M hydrochloric acid (HCl), and the extract was used to measure iron (Fe), ammonium (NH4)-N, nitrate (NO3)-N, sulfur (S), and zinc (Zn). Conventional soil tests were completed on incubated soils (60 or 120 days). Resin capsules reflected NH4-N and P fertilizer applied at low rates in the loamy sand but not in the sandy clay loam. Neither Fe nor Zn application was reflected in resin capsules, but the accompanying S was clearly quantified. In comparison to conventional soil test procedures, resin capsule NH4-N was clearly a better indicator than KCl-extractable NH4-N; resin capsule NO3-N was effective, but not as good an indicator as water extraction; and resin capsule P was reflective of soil applied P in loamy sand but not in sandy clay loam, whereas sodium bicarbonate was effective in both soils. Resin capsules show promise for use in low-input conditions, but additional understanding of interactions in variable soils is needed. 相似文献
80.
采用盆栽试验,研究了水分管理和钝化剂处理对红壤性水稻土重金属镉的钝化效应及其作用机理。结果表明,在土壤镉含量为0.75mg·kg。下,添加海泡石复配磷肥可以显著提高土壤pH值,长期淹水、常规管理水分条件下,土壤交换态cd分别降低了20.4%和15.7%,碳酸盐结合态cd分别下降了15.5%和14.1%,糙米cd分别降低了52.3%和46.O%。未添加钝化剂条件下,长期淹水处理的根表Fe(Ⅱ)含量比常规处理增加了1.2倍,根表cd含量则是常规处理的82.6%。土壤经钝化处理后,长期淹水和常规管理水分条件下,根表Fe(Ⅱ)分别增加了40.1%和70.0%,而根表cd分别降低了35.3%和42.4%。糙米cd含量与根表Fe(Ⅱ)含量呈显著负相关,与根表cd含量呈显著正相关。土壤Fe“和cd“对水稻根表吸附点位的竞争以及土壤镉较低的生物有效性是钝化处理组糙米镉含量下降的主要原因。 相似文献