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1.
Three strains of mice (NMRI, C57/BL, BALB/c) were each immunized with a 12 kDa purified, native Fasciola hepatica fatty acid binding protein (Fh12) and challenged percutaneously with Schistosoma bovis cercariae. C57/BL mice immunized with Fh12 had significant reductions in S. bovis worm burden recoveries (96 and 87% reductions over controls in two separate experiments). When using NMRI or BALB/c mice, Fh12 alone or in Freund's adjuvant failed to induce significant protection against S. bovis. In C57/BL mice vaccinated against Fh 12, antibodies to the IgG2a isotype, but not to the IgG1 isotype, increased by 2 weeks after the second immunization and remained high through 8 weeks of S. bovis infection. Antibodies to S. bovis increased after 4 weeks of infection. Regarding cytokine production by spleen mononuclear cells, C57/BL mice vaccinated with Fh12 in adjuvant, and having the highest protective response against challenge infection with S. bovis, had an increase of IFN-gamma production with Concanavalin A but no increase of IL-4 in similarly stimulated cells. These results suggest that the protection obtained in this group of mice is mediated by a Th1 immune response.  相似文献   

2.
Fatty acid binding proteins (FABP) have been designed as a potential vaccine against fasciolosis. In this work, the immunoprophylaxis of the recombinant Fh15 FABP from F. hepatica (Fh15) in adjuvant/immunomodulator ADAD system was evaluated using mice and sheep challenged with F. hepatica. The ADAD system combines the Fh15 antigen with an immunomodulator (hydroalcoholic extract of Polypodium leucotomos; PAL) and/or an adjuvant (saponins of Quillaja saponaria; Qs) in a water/oil emulsion (30/70) with a non-mineral oil (Montanide). All the infected control mice died by 41-48 days post-infection. The mice vaccinated with ADAD only with PAL+Fh15 present a survival rate of 40-50% and those vaccinated with ADAD containing PAL+Qs+Fh15 had a survival rate of 50-62.5%. IgG1 antibodies were lower in surviving mice in comparison with non-surviving mice. The sheep vaccinated with ADAD PAL+Qs+Fh15 showed lower fluke recovery (43%), less hepatic lesions and higher post-infection daily weight gain than F. hepatica infected control animals. Thus, the ADAD system using recombinant fatty acid binding proteins from F. hepatica could be a good option to develop vaccines against F. hepatica.  相似文献   

3.
Fatty acid binding proteins (FABP) have shown protective immune response against Fasciola hepatica infection. We evaluated the protection induced by the Fh12 FABP from F. hepatica (Fh12) combined with the new immunomodulator the lipidic aminoalcohol OA0012 in the ADAD system in mice and sheep. In this work we introduced a lipidic aminoalcohol OA0012 as immunomodulator alone or in combination with the hydroalcoholic extract of Phlebodium pseudoaureum; PAL. Mice vaccinated with ADAD containing OA0012+Fh12 or OA0012+Qs+Fh12 had survival rates of 40-50%. Sheep ADAD-vaccinated with OA0012+Qs+Fh12 showed lower fluke recovery, less hepatic lesions and higher post-infection daily weight gain than F. hepatica infected control animals. Sheep ADAD-vaccinated with OA0012 combined PAL and Qs+Fh12 showed lower fluke recovery (42%), lower adult worms count (57%) lower faecal egg count (38%), less hepatic lesions and higher post-infection daily weight gain than F. hepatica infected control animals. Thus, the addition of a new immunomodulator of synthesis to ADAD system with FABPs increased the protection against F. hepatica.  相似文献   

4.
The aim of this study was to investigate the cross-resistance between Fasciola hepatica and Schistosoma bovis in lambs assessing parasitologic, gross pathologic, histopathologic and immunohistochemical changes in liver and small intestine. Thirty Castellana breed lambs were divided into five comparable groups and exposed to F. hepatical S. bovis (group F/S), S. bovis/F. hepatica (group S/F), S. bovis (group S) or F. hepatica (group F) and six unexposed lambs were used as non-infected controls (group C). Primary patent infection with F. hepatica induced a lower number of schistosome eggs and a higher number of lymphocytes in intestinal and liver schistosome egg-induced granulomas in group F/S than in the groups S/F and S, liver damage being mainly attributed to F. hepatica. S. bovis infection followed by challenge with F. hepatica particularly increased the severity of the most significant liver alterations (cholangiohepatitis by F. hepatica and mesoendophlebitis by S. bovis) and F. hepatica seemed not to have an influence on established S. bovis infection. In addition, immunohistochemical results suggested that the predominant local immune response in both double-infected groups was different, being mainly a cell-mediated immune response in group F/S and a mucosal response in group S/F.  相似文献   

5.
为筛选出特异的肝片吸虫诊断候选抗原,拓展诊断靶标,利用肝片吸虫阳性血清筛选肝片吸虫cDNA表达文库,获得肝片吸虫特异性抗原基因,采用RT-PCR技术扩增目的基因,连接表达载体pET-32a(+),构建重组质粒,转化入感受态细胞BL21(DE3)中,利用IPTG对重组蛋白进行诱导表达,通过SDS-PAGE及Western blot技术对蛋白表达情况进行鉴定。结果显示:经筛选获得了17个肝片吸虫免疫显性抗原基因,其中假定蛋白Fh010935为肝片吸虫特异性抗原基因;扩增得到的Fh010935核苷酸序列大小为144 bp,编码48个氨基酸,A+T含量为55.56%;Fh010935蛋白由1个α-螺旋,2个β-折叠和3个β-转角构成,具有3个抗原表位,推测该蛋白可能具有较好的抗原性;重组蛋白主要以包涵体形式表达,分子量大小约24 ku,可以被肝片吸虫感染阳性血清特异性识别,具有较好的反应原性。提示:假定蛋白Fh010935可作为肝片吸虫病诊断候选抗原,为疾病诊断制剂的开发提供前期基础。  相似文献   

6.
为筛选出特异的肝片吸虫诊断候选抗原,拓展诊断靶标,利用肝片吸虫阳性血清筛选肝片吸虫cDNA表达文库,获得肝片吸虫特异性抗原基因,采用RT-PCR技术扩增目的基因,连接表达载体pET-32a(+),构建重组质粒,转化入感受态细胞BL21(DE3)中,利用IPTG对重组蛋白进行诱导表达,通过SDS-PAGE及Western blot技术对蛋白表达情况进行鉴定。结果显示:经筛选获得了17个肝片吸虫免疫显性抗原基因,其中假定蛋白Fh010935为肝片吸虫特异性抗原基因;扩增得到的Fh010935核苷酸序列大小为144 bp,编码48个氨基酸,A+T含量为55.56%;Fh010935蛋白由1个α-螺旋,2个β-折叠和3个β-转角构成,具有3个抗原表位,推测该蛋白可能具有较好的抗原性;重组蛋白主要以包涵体形式表达,分子量大小约24 ku,可以被肝片吸虫感染阳性血清特异性识别,具有较好的反应原性。提示:假定蛋白Fh010935可作为肝片吸虫病诊断候选抗原,为疾病诊断制剂的开发提供前期基础。  相似文献   

7.
采用PCR方法对编码金黄色葡萄球菌黏附素纤连结合蛋白A(FnbpA)的A区基因片段进行了特异性扩增,构建了真核表达载体pVAX-SFn,转染BHK-21细胞后经ELISA可检测出分泌表达的FnbpA蛋白。将真核重组表达质粒肌肉注射C57BL/6小鼠,免疫后检测小鼠血清抗体效价、淋巴细胞增殖及对试验小鼠攻毒试验。结果表明,该重组表达载体诱导细胞和体液免疫应答的强度均明显超过对照组。对小鼠的攻毒试验结果提示该重组DNA经肌肉注射途径接种可对小鼠产生免疫保护。本试验的结果对该DNA疫苗今后在实际中的应用奠定了良好的试验基础。  相似文献   

8.
试验旨在确定牛支原体P48基因的免疫原性,为进一步筛选牛支原体免疫保护性基因奠定基础。本研究以牛支原体新疆分离株为研究对象,运用Overlap PCR方法扩增得到点突变后的牛支原体新疆分离株P48基因,构建原核表达载体pET-32a (+)-P48,转化大肠杆菌BL21(DE3)感受态细胞,在诱导剂ITPG的诱导下获得重组蛋白P48,纯化后的重组P48蛋白免疫BALB/c小鼠制备多克隆抗体,运用Western blotting和ELISA方法验证其反应原性和免疫原性。结果表明,试验成功构建原核表达载体pET-32a (+)-P48,重组蛋白P48大小约为66 ku,纯化后的牛支原体P48重组蛋白免疫小鼠后可产生良好的免疫反应,血清抗体滴度达到较高水平(D450 nm值为1.126)。Western blotting结果显示,抗牛支原体P48重组蛋白的鼠血清与牛支原体P48重组蛋白及牛支原体全菌蛋白抗原均能产生明显的抗原抗体反应,表明P48重组蛋白具有良好的免疫原性与反应原性,可作为牛支原体新型疫苗的候选基因,且牛支原体新疆分离株P48基因与国内外5株牛支原体P48基因的同源性很高,亲缘关系较近。  相似文献   

9.
The potential of a recombinant Schistosoma bovis 28-kDa glutathione S-transferase (rSb28GST) to protect cattle against Fasciola hepatica was tested in a vaccination trial. Thirty two calves were randomly divided into four groups of eight animals. Calves of the three vaccine groups received two intramuscular injections at 3 weeks interval, of 0.250mg rSb28GST in either aluminium hydroxide (Al(OH)(3)), Quil A, or PBS emulsified in an equal volume of Freund's complete adjuvant (FCA).Animals of the control group received injections of Al(OH)(3)/PBS only. All animals were challenged orally with a total of 360 metacercariae of F. hepatica, spread over 6 weeks.All groups of vaccinated animals produced measurable IgG antibody titers to rSb28GST after vaccination. Animals immunised with FCA adjuvanted vaccine had the highest and more durable antibody titers and only sera from this group recognised an approximately 24kDa protein band from F. hepatica, that is thought to be a F. hepatica GST. Despite a good antibody response differences in cumulative faecal egg output between the groups were not statistically significant. In addition, no significant difference was found between groups in terms of total worm numbers or percentage of immature flukes recovered at necropsy. In conclusion, the recombinant S. bovis 28kDa GST was not found to adequately protect cattle against experimental F. hepatica challenge, using either aluminium hydroxide, Quil A or FCA as adjuvant.  相似文献   

10.
We evaluate the ability of a Fasciola hepatica FABP native antigen (Fh12) with a new vaccination system called ADAD to protect mice and sheep against an experimental F. hepatica infection. The vaccination protocol consists of a set of two injections. The first injection contains a micelle in which two components are included, saponin from Quillaja saponaria (Qs) and/or Anapsos (A) a Polypodium leucotomos hydroalcoholic extract, both emulsified in a non-mineral oil (Montanide) in a water/oil emulsion (30/70). This is subcutaneously injected to achieve the "adaptation" of the immune system to subsequent stimuli. The second injection contains in addition the Fh12 antigen. Two different experiments were carried out using two mouse strains (BALB/c and CD-1). Mice vaccinated with Qs+A+Fh12 presented a survival rate of 40%, when compared with control groups. Furthermore, we evaluated the efficiency of the vaccination in sheep against an experimental F. hepatica challenge. The vaccinated sheep presented lower fluke recovery (24.5%), number of eggs in bile fluid (58.1%) and faeces (40.3%) than control groups. The recovered flukes were shorter (32.7%), immature (34.0%) and with lower body mass (31.6%) than non-complete vaccinated sheep. Thus, the new ADAD system could be a good alternative for future vaccination experiments against fasciolosis.  相似文献   

11.
为获得高特异性的抗隐孢子虫单克隆抗体(monoclonal antibody,McAb),以原核表达的隐孢子虫鼠基因型(Cryptosporidium mouse genotype)子孢子表面抗原CP15/60为免疫原,免疫Balb/c小鼠。取免疫鼠脾细胞与SP2/0细胞进行融合,用间接ELISA方法进行抗体效价测定,有限稀释法进行亚克隆。以常规染色体分析法进行杂交瘤细胞的染色体分析,用McAb亚类鉴定试剂盒鉴定McAb亚型、间接ELISA法测定相对亲和力及交叉反应性、Western blot检测抗体的特异性。结果获得了2株能稳定分泌抗重组CP15/60(recombinant CP15/60,rCP15/60)的单克隆抗体杂交瘤细胞株,分别命名为B4F7和D8H5,其腹水抗体效价均达到1∶107;染色体数目B4F7株为97条±4条、D8H5株为90条±7条,且观察到标志染色体;McAb亚型均为IgG1,轻链均为κ链;相对亲和力常数B4F7株为0.009μg/mL、D8H5株为0.016μg/mL;2种McAb均与rCP15/60蛋白发生特异性反应,与柔嫩艾美耳球虫卵囊可溶性蛋白、弓形虫裂殖子蛋白以及日本血吸虫虫体蛋白均无交叉反应,证实本试验获得了2株高特异性的抗隐孢子虫McAb。  相似文献   

12.
The antibody response to the recombinant protein, R32tet32, which contained the repetitive sequence (NANP)n of Plasmodium falciparum CSP was determined in C57BL/6 mice during the course of nonlethal infection with Plasmodium yoelii 17X. Marked suppression of the IgG antibody response to R32tet32 occurred when mice were immunized at peak parasitemia (on day 16). In vitro antibody responses of spleen cells from acutely infected mice to R32tet32 were similarly suppressed. Stimulation of normal spleen cells cultured for 5 days with 100 ng/ml of R32tet32 gave an optimal IgG antibody response, but spleen cells from infected mice obtained at peak parasitemia failed to respond to a broad range of antigen concentrations. Cocultivation studies employing enriched lymphocyte populations from infected and uninfected C57BL/6 mice indicated that both T and B cells from infected mice were defective in their response to R32tet32. The response to the repetitive region was restored by the addition of recombinant mouse interleukin-2 (IL-2) at a dose of 50 U/ml to cultures of spleen cells from infected mice.  相似文献   

13.
Immunity of schistosomes using heterologous trematode antigens--a review   总被引:1,自引:0,他引:1  
This review summarizes the field of cross-protection in schistosomiasis due to other parasitic infections and with subcellular fractions of the parasite trematodes. Regarding parasitic infections, the clearest evidence of cross-protection to Schistosoma mansoni was found with the trematodes, particularly with Fasciola hepatica. Evidence was also presented which demonstrated that the protective F. hepatica worm antigens were those which bound to antibodies to S. mansoni, and that as antigen purification proceeded, smaller amounts were required to obtain significantly high levels of protection. These 2 factors, cross-reactivity and improved protection with increasing antigen purity (and possibly improved immunogenicity), are both supportive of an immunological basis for protection against S. mansoni. A Fasciola/Schistosoma-defined immunity cross-reactive antigen from F. hepatica worms was isolated and designated as FhSmIII(M). An antiserum to this antigen was developed and used as a probe to detect the presence of this antigen (or its determinants) in different extracts of parasitic trematodes. In this manner, it was possible to demonstrate that FhSmIII(M) (or at least some of its determinants) were found on (or in) S. mansoni, S. bovis and Paragonimus westermani. Since mice immunized with P. westermani worm extracts acquire resistance to challenge with S. mansoni cercariae, a common link of cross-protection to the parasitic trematodes is suggested; i.e., FhSmIII(M). Although immunity to schistosomes is undoubtedly multifactorial, the demonstration of a common protective antigen (or determinant) will provide a handle for the evaluation of additional candidate protective antigens.  相似文献   

14.
Virus-free supernatants of cultured swine monocytes infected by African swine fever virus (ASFV) suppressed in vitro proliferation of porcine and human blood mononuclear cells in response to phytohemagglutinin and the in vivo primary immune response of C57BL/6 mice against sheep RBC. The supernatants were fractionated by discontinuous ion-exchange chromatography and subfractionated by double-step preparative isoelectric focusing. The pool of the most purified active subfractions (F5'EP-ASFV) is made up of heat-unstable material, can be stained by silver nitrate, and has an isoelectric point of 3.88, a maximal optical density at 280 nm, and a mass of 36,000 daltons. In vivo kinetic studies in nonimmunized C57BL/6 mice were performed on days 1, 2, 3, 5, and 7 after injection with 50 micrograms of F5'EP-ASFV protein. Compared with the untreated mice, the treated mice had a noticeable increase in nonspecific immunoglobulin-secreting splenic plaque-forming cells (PFC) with the following isotype profile: IgG2a greater than IgG2b greater than IgG3 greater than IgG1 congruent to IgM. Three days after treatment with the active material, specific IgM PFC against sheep RBC increased up to 23-fold. In C57BL/6 mice immunized against sheep RBC 2 days after treatment with F5'EP-ASFV, the increase in nonspecific PFC was followed by a suppression of specific PFC response in the respective isotype. When C57BL/6 mice were treated after priming with sheep RBC, however, there was little or no suppression of specific PFC and the increase in nonspecific PFC was considerably lower than that in the other F5'EP-ASFV-treated mice. In this case, kinetic curves of specific vs nonspecific PFC of each isotype were mirror images. Mice treated with 200 micrograms of F5'EP-ASFV protein died with hemorrhagic diastasis.  相似文献   

15.
为制备能够特异性识别牛分枝杆菌(M.bovis)抗酸蛋白酶(MarP)的特异性单克隆抗体(MAb),本研究利用大肠杆菌表达系统表达了MarP蛋白的胞浆区,并以β-casein为底物、DTT为抑制剂检测MarP的丝氨酸蛋白酶活性。以具有活性的MarP蛋白免疫小鼠,取脾细胞与SP2/0细胞融合,并加入饲养层细胞轻轻摇匀分装于96孔培养板,置于37℃、5% CO2培养箱内培养10 d,通过IFA和间接ELISA筛选阳性细胞株进行亚克隆,制备能分泌针对MarP MAb的杂交瘤细胞株,并通过Western blotting和ELISA检测MAb与重组表达和天然的MarP蛋白的反应性。结果显示,重组表达的MarP具有良好的丝氨酸蛋白酶活性,能够在12 h内将30 μg的β-casein酶解完全,DTT能够抑制MarP的酶活性。具有活性的MarP蛋白免疫小鼠后,获得5株针对MarP的MAb,均能够特异性识别重组和牛分枝杆菌天然表达的MarP蛋白的线性表位,而不与大肠杆菌(E.coli)和耻垢分枝杆菌(M.smegmatis)的蛋白反应。本研究成功制备了MarP蛋白及MAb,为进一步研究MarP的作用底物及其在牛分枝杆菌抗酸胁迫中作用机制提供了必备材料。  相似文献   

16.
为克隆、表达日本血吸虫假想蛋白SJCHGC068068编码基因(暂命名为Sj06868)并观察重组抗原的免疫预防效果。应用PCR技术从日本血吸虫7 d童虫、14 d童虫mRNA反转录制备的cDNA中克隆到Sj06868基因的46-438 bp DNA片段,BLASTn分析未发现其他物种中的同源性序列,也未发现其保守序列和相关功能结构域。以pET32a为表达载体、Sj06868基因在大肠杆菌Rosetta(DE3)中获得高效表达,表达产物rSj068068分子量为36 kDa,能被感染血吸虫14 d兔血清识别。将纯化的重组抗原与佐剂ESSAI ISA 206 CELL混合后免疫BALB/c小鼠,与佐剂对照组和PBS对照组相比,分别获得了31.63%、29.19%减虫率以及55.63%、56.27%肝脏虫卵减少率。用ELISA检测各组血清中抗rSj068068特异性抗体结果显示,免疫组在攻击感染前、佐剂对照组和PBS对照组在感染后均产生了较高水平的特异性抗体。本研究结果说明,Sj068068是日本血吸虫特有的童虫期高表达基因,rSj068068在抗血吸虫疫苗和血吸虫感染的诊断方面均有潜在应用价值。  相似文献   

17.
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   

18.
本研究旨在获得重组C型肉毒梭菌毒素蛋白,并评价其免疫保护性。将麦芽糖蛋白(MBP)和C型肉毒梭菌毒素重链C末端(CHC)的编码基因序列进行优化和串联,获得基因片段GMBPCHC。将GMBPCHC克隆至pET28a-(+)后转化大肠杆菌BL21(DE3)感受态细胞,分别在15和37℃两种温度条件下诱导表达。利用Ni-IDA亲和层析方法对可溶性表达的目的蛋白进行纯化,从而获得重组蛋白rMBPCHC。将rMBPCHC与Montanide ISA 201佐剂混合制备成疫苗,免疫4只家兔,剂量为100 μg/只。根据《中华人民共和国兽药典》(2015年版)规定的方法检测一免后21 d及二免后14 d家兔血清的中和抗体效价。同时,在二免后14 d对家兔进行攻毒。结果表明,rMBPCHC在37℃的诱导温度下,主要以包涵体的形式表达;在15℃的诱导温度下,可溶性表达的比例可达50%。一次免疫后,免疫组4只家兔血清对C型肉毒梭菌天然毒素(简称天然毒素)的中和效价均可达到1(0.1 mL血清中和1个小鼠最小致死量(MLD)的天然毒素)。二免后,家兔血清的中和抗体效价可达到4~8。用10个家兔MLD的天然毒素攻毒后,免疫组家兔得到了100%(4/4)的保护,而用1个家兔MLD的天然毒素攻毒后,对照组家兔100%(2/2)死亡。以上结果说明,rMBPCHC具有良好的免疫原性,从而为C型肉毒梭菌病基因工程亚单位疫苗的研制提供了重要的试验数据。  相似文献   

19.
The role of T cells in immunity to Cowdria ruminantium was investigated by studying the responses to infection of normal, athymic, CD4(+) T cell knock out (KO) and CD8(+) T cell KO C57BL/6 mice. Normal C57BL/6 mice could be immunized by infection and treatment, and immunity was adoptively transferable from immune to naive mice by splenocytes. Following infection, athymic mice died sooner than normal mice (P=0.0017), and could not be immunized by infection and treatment. CD4(+) T cell KO mice were as susceptible to infection as normal mice and could be immunized by infection and treatment. In contrast, CD8(+) T cell KO mice were less susceptible than normal and CD4(+) T cell KO mice and 43% self-cured, while those that died did so after a prolonged incubation period. Antibody responses to C. ruminantium were CD4(+) T cell dependent, because responses were detected in immune normal and CD8(+) T cell KO mice but not in immune CD4(+) KO mice (P=0.005). Since CD8(+) T cell KO mice were less susceptible to infection, and since CD4(+) T cell KO mice could be immunized, it can be concluded that immunity to C. ruminantium can be mediated by both CD4(+) and CD8(+) T cells.  相似文献   

20.
采用统计学计算Tg(Mosprn-B)/C57BL/6转基因小鼠与C57BL/6野生型小鼠雌雄两性的主要脏器质量与系数,并利用水迷宫观察游泳路径及时间以探讨SPRN基因对小鼠生理结构、生长发育等影响。结果表明,相同年龄的Tg(Mosprn-B)/C57BL/6转基因小鼠,雄性的体质量及心、肺、肝、肾质量显著大于雌性(P<0.01),脑质量差异比较显著(P<0.05);比较脏器系数,脑和肝的差异比较显著(P<0.05)。与C57BL/6野生型小鼠相比较,Tg(Mosprn-B)/C57BL/6转基因小鼠脑更重(P<0.01);比较脏器系数发现,脑差异极显著(P<0.01),肺、肾、脾差异较显著(P<0.05)。水迷宫定位航行结果显示,Tg(Mosprn-B)/C57BL/6转基因小鼠的逃避潜伏期小于野生型小鼠,第4天的潜伏期具有显著差异性(P<0.05);在空间搜索试验中,Tg(Mosprn-B)/C57BL/6转基因小鼠第1次穿越平台时间小于C57BL/6野生型小鼠,穿越平台的次数大于C57BL/6野生型小鼠。  相似文献   

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