细粒棘球蚴原头节18ku纯化抗原ELISA的建立及其对两型包虫病鉴别诊断的意义

目的 用细粒棘球蚴原头节18ku纯化抗原建立ELISA诊断方法,用于两型包虫病的鉴别诊断。方法 用18ku纯化抗原ELISA方法对44例泡型包虫病（AE）、70例囊型包虫病（CE）、29例囊虫病和30例健康人血清中特异性抗体进行检测,同时用羊包囊液抗原（Bu)常规ELISA法检测上述血清做比较。结果 18ku纯化抗原检测不同血清的阳性率为：AE90．91％、CE111．43％、囊虫病和健康人血清均为阴性;Bu抗原分别为：AE97．73％、CE88．57％、囊虫病51．72％和健康人10．0％。18ku-ELISA对AE血清诊断敏感性为90．91％、特异性93．80％、阳性预示值为83．33％、阴性预示值96．80％。结论 两型包虫病患者体内18ku抗体水平存在明显差异,纯化抗原18ku-ELISA可用于两型包虫病的鉴别诊断、较免疫印渍法简便快速。     

Em18重组抗原特异性抗体的制备及对循环抗原检测的初探

目的 用Em18重组抗原ReEm18制备特异性抗体,建立双抗体夹心ELISA,检测患者血清中的循环抗原.方法 ReEm18经亲和纯化,免疫BALB/c小鼠和新西兰兔,分别制备单克隆抗体(单抗)和多克隆抗体(多抗).用获得的单抗和多抗建立双抗体夹心ELISA,检测患者血清中Em18循环抗原.结果 免疫兔血清抗ReEm18抗体效价达1∶204 800以上.经ReEm18和多房棘球蚴病(AE)患者血清及健康人血清阻断ELISA试验双重筛选融合细胞,共获得14株抑制率＞50%的特异性阳性细胞克隆.将特异性单抗和多抗自由组合进行双抗体夹心ELISA,结果以9号单抗与多抗的配对检测抗原为最优,检测ReEm18的灵敏度达3 ng/m1.用建立的双夹心ELISA方法检测血清,11份AE血清中6份为阳性.结论 获得针对ReEm18的特异性单抗和多抗,建立了敏感的双抗体夹心ELISA方法,血清学初步检测结果表明AE血清中存在可检测的Em18循环抗原.     

包虫病人循环抗原的检测及应用价值的探讨

利用亲和层析纯化的抗包虫免疫球蛋白以双抗体ELISA法检测包虫抗原,对经亲和层析纯化的包虫抗原的检出下限可达40ng/ml。以1:2健康人混合血清稀释抗原时,检出下限为2.5μg/ml。用此法检测79例包虫病人的循环抗原,阳性率为40.51％。其中肝包虫病人阳性率为38.98％,肺包虫病人为33.33％。血清抗体阳性的包虫病人循环抗原检出率为33.33％,抗体阴性者中为43.75％。在抗体阴性的肺包虫病人中循环抗原的阳性率可达50％。循环抗原的测定在血清抗体阴性包虫病人的免疫学诊断中具有辅助意义。     

18kDa抗原诊断泡型包虫病的评价

目的：评价１８ｋＤａ抗原在泡型包虫病（ＡＥ）诊断中的价值。方法：用免疫印渍法检测３３例泡型包虫病、６９例囊型包虫病（ＣＥ）、３０例囊虫病和８２例健康人血清对泡型棘球蚴（Ｅｍ）和囊型棘球蚴（Ｅｇ）原头节１８ｋＤａ抗原的抗体反应。同时用羊包囊液抗原常规ＥＬＩＳＡ法检测上述血清。结果：ＥＬＩＳＡ试验,ＡＥ血清阳性率为９３．９％、ＣＥ为８５．５％、囊虫病为５０％、健康人为６．１％。显示３种患者血清存在较强的交叉反应。免疫印渍试验,两种原头节的１８ｋＤａ抗原对ＡＥ血清阳性反应均为９０．９％、ＣＥ分别为１０．１％和１３％、囊虫病患者为１３．３％和１６．７％。与健康人血清不发生反应。结论：１８ｋＤａ抗原可以有效的鉴别两型包虫病。     

细粒棘球蚴重组抗原B 8-kDa亚单位1对囊型包虫病的血清学诊断价值

目的通过基因工程技术获得细粒棘球蚴抗原B8-kDa亚单位1重组蛋白(rEgAgB8/1),探讨其对囊型包虫病(CE)的血清学诊断价值。方法将构建的rEgAgB8/1原核表达质粒(pET32b-rEgAgB8/1)转化至E.coli BL-21(DE3)中,用IPTG诱导表达,经亲和层析纯化获得高纯度rEgAgB8/1,以rEgAgB8/1为抗原,应用ELISA和Immuno blotting方法对31例手术确诊的囊型包虫病病人血清进行了回顾性检测与分析。结果ELISA和Immuno blotting方法检测CE病人血清阳性率均为90.3%(28/31),3例血清学检测阴性的CE病人均为初次诊断为CE及单纯性肝脏单发感染的病人;血清抗体水平随着病人棘球蚴囊数目增加而有所增加,棘球蚴囊的数目与血清抗体水平的比较用单因素方差分析有显著性差异(F=5.06,P=0.0142),1个囊与2个囊/3个囊组间血清抗体水平有显著差异,2个囊与3个囊组间差异无统计学意义。结论rEgAgB8/1重组蛋白抗原对囊型包虫病有较高的血清学诊断价值,多囊型包虫病人血清抗体水平高于单囊型包虫病人。     

人体囊虫病诊断试剂盒的效果评价

目的评价囊虫IgG抗体检测试剂盒的诊断效果,为临床应用提供参考。方法按照囊虫IgG抗体检测试剂盒说明书,采用ELISA法检测囊虫病、包虫病、带绦虫病及健康人血清。结果在30例活动期脑囊虫病病人中,28例呈囊虫IgG抗体阳性,敏感性为93.33%。100份健康人血清均无阳性反应。在42例带绦虫感染者,2例囊虫抗体阳性,阳性率为4.76%。在60份包虫病血清中,阳性41份,该试剂盒与包虫病的交叉反应率为68.33%。结论所评价试剂盒敏感性较好,但特异性差,与包虫病的交叉反应率高。以上提示国内囊虫病免疫学诊断试剂的质量有待提高。     

华支睾吸虫成虫14～33 ku抗原诊断价值的研究

目的探讨纯化华支睾吸虫成虫14~33 ku抗原在华支睾吸虫病免疫诊断中的应用价值。方法使用SDS-PAGE和电洗提法,从可溶性华支睾吸虫成虫抗原中分离纯化14~33 ku抗原,用此抗原经ELISA方法检测华支睾吸虫病、卫氏并殖吸虫病、日本血吸虫病、姜片虫病患者血清及健康人血清特异性IgG抗体,并与粗制可溶性成虫抗原和可溶性成虫脱脂抗原ELISA结果相比较。结果检测63例华支睾吸虫病患者血清,纯化华支睾吸虫成虫14~33 ku抗原ELISA阳性率为76.2%,可溶性成虫抗原和可溶性成虫脱脂抗原ELISA阳性率均为100%;检测25例卫氏并殖吸虫病、85例日本血吸虫病、27例姜片虫病患者血清,14~33 ku抗原的ELISA交叉反应阳性率分别为8.0%、3.5%、0,而可溶性成虫抗原分别为80.0%、62.4%、14.8%,可溶性成虫脱脂抗原分别为64.0%、55.3%、7.4%;检测127例健康人血清,14~33 ku抗原的ELISA假阳性率为0,可溶性成虫抗原和可溶性成虫脱脂抗原的假阳性率分别为5.5%、3.1%。结论纯化华支睾吸虫成虫14~33 ku抗原用于华支睾吸虫病免疫诊断的特异性优于粗抗原,但敏感性较低。     

纯化抗原和粗抗原诊断包虫病的效果比较

目的比较纯化细粒棘球蚴囊液抗原和囊液粗抗原诊断包虫病的效果。方法用 Burstein法纯化抗原 ,与粗抗原平行同步检测包虫病病人、健康人及其它寄生虫病病人血清 ,以标化阳性预告值 ( SPPV) ,标化阴性预告值 ( SNPV) ,标准化准确度 ( SAc)等计算综合积分指数 ( SII)。结果两种抗原检测包虫病病人与健康人 ,其 SII值 :纯化抗原为 96 .0 % ,粗抗原为 95 .5 %。包虫病与其他寄生虫病 ,其 SII值 :纯化抗原为 94 .9% ,粗抗原为92 .8%。结论表明 Burstein法纯化抗原在诊断包虫病的质和量上均优于囊液粗抗原。     

单克隆抗体夹心ABC-ELISA检测包虫病人循环抗原

应用生物素标记单克隆抗体进行夹心ABC-ELISA检测包虫病人血清循环抗原(HcAg),共检测包虫病人血清103份,62价呈阳性(60.19％);检测囊虫病人血清22份,其它寄生虫病血清54份,正常人血清101份,均未出现假阳性反应。常规ELISA血清抗体阴性的10例包虫病人HcAg 5例呈阳性。HcAg的检测对血清抗体阴性的包虫病人具有辅助诊断意义。     

多房棘球蚴病特异性诊断抗原Em18的基因克隆、表达和血清学评价

目的　克隆从我国四川省分离的多房棘球绦虫Em18抗原基因片段,表达重组抗原,用于多房棘球蚴病(AE)的诊断,并用患者血清对其诊断价值进行评价。　方法　PCR扩增目的基因片段与质粒载体pET28a(+)连接构建表达质粒,转化大肠埃希菌BL21(DE3)菌株表达重组蛋白,用镍次氮基三乙酸琼脂糖树脂(NI NTAagarose)亲和层析纯化重组抗原,酶联免疫吸附测定(ELISA)评价重组抗原的血清学诊断效果。　结果　获得两个高效表达克隆ReEm181和ReEm182。其中ReEm181与预期序列一致,ReEm182为同一序列,但有27bp的核苷酸缺失。两个克隆表达的融合蛋白相对分子质量(Mr)分别为28000和26000。对101例AE、47例细粒棘球蚴病、30例囊尾蚴病、10例肝癌、9例血吸虫病和40名健康人共237份血清进行ELISA检测 ,结果显示,ReEm181和ReEm182重组抗原对AE血清诊断的敏感性为861%和901%、特异性为934%和941%、阳性预期值为906%和919%、阴性预期值为901%和928%、诊断效率分别为903%和924%;对58例AE患者肝脏病灶大小与重组抗原检测血清平均吸光度(A)的相关性比较分析结果表明,抗体反应水平在病程早期有较好的相关性。　结论　Em18重组抗原对AE具有特异性诊断价值     

细粒棘球蚴粗抗原的免疫纯化方法及其在免疫诊断中的应用

采用免疫过筛法将细粒棘球蚴囊液粗抗原（ＥｇＣＦ）和头节抗原（ＥｇＰ）与正常人混合血清中杂抗体结合而除去产生非特异反应的粗抗原部分,得到部分纯化的抗原ＥｇＣＦ２,ＥｇＰ２,纯化前后的抗原在酶联免疫吸附试验（ＥＬＩＳＡ）及斑点免疫结合试验（ＤＩＢＡ）中对４５例细粒棘球蚴病（ＣＥ）的诊断阳性率分别为：ＥｇＣＦ９３．３％,ＥｇＰ９５．６％,ＥｇＣＦ２９１．１％,ＥｇＰ２９３．３％,它们的敏感性无显差异。     

Differential serodiagnosis for cystic and alveolar echinococcosis using fractions of Echinococcus granulosus cyst fluid (antigen B) and E. multilocularis protoscolex (EM18)

Echinococcus granulosus cyst fluid and E. multilocularis protoscolex extract were fractionated by a single step of preparative isoelectric focusing, resulting in an antigen B-rich fraction (8-kD) and an Em18-rich fraction, respectively. The usefulness of both fractions for differential serodiagnosis of cystic (CE) and alveolar (AE) echinococcosis was evaluated by a large-scale immunoblot analysis on a battery of 354 serum samples. These included 66 from AE patients originating from four different endemic areas, 173 from CE patients originating from seven different endemic areas, 71 from patients with other parasitic diseases, 15 from patients with hepatomas, and 29 from healthy individuals. In an immunoblot with the antigen B-rich fraction, 92% (158 of 173) of the CE sera as well as 79% (52 of 66) of the AE sera reacted with the 8-kD subunit. No cross-reactivity occurred with any sera from patients with cysticercosis, other parasitic diseases, or with hepatomas, or from healthy controls. In an immunoblot with the Em18-rich fraction, all but two sera from AE patients (64 of 66, 97%) recognized Em18, and only nine of 34 CE sera from China reacted with it. All other (139) CE sera from six other countries were negative as were all (115) other non-echinococcosis sera. These findings indicate that antigen B (8-kD) is not species-specific for E. granulosus but is genus-specific for Echinococcus, and that the Em18 antigen is a reliable serologic marker for species-specific differentiation of AE from CE.     

Development of Em18-immunoblot and Em18-ELISA for specific diagnosis of alveolar echinococcosis

Extensive experience has documented that Em2(plus)-ELISA, Em10-ELISA and Em18-immunoblot and Em18-ELISA are reliable serologic methods for detection of alveolar echinococcosis (AE) caused by the metacestodes of Echinococcus multilocularis. Among these, tests based on detection of antibodies to the specific Em18 antigen, either immunoblot or ELISA, appears to be the most specific for AE. Between 90 and 97% of AE cases with characteristic hepatic lesions detectable by image analysis have been positive in Em18-serology. In contrast Antigen B (8 kDa)-immunoblot is the most sensitive for all forms of echinococcosis, although it can not differentiate AE from cystic echinococcosis (CE). Primary serologic screening for echinococcosis, especially for CE using hydatid cyst fluid of Echinococcus granulosus appears to be highly sensitive in endemic areas. Glycoproteins (GPs) purified from cyst fluid of Taenia solium are highly specific for diagnosis of T. solium neuorcysticercosis (NCC). Using currently available antigens it is not difficult to differentiate these three larval cestodiases serologically. We recommend that (1) primary screening of CE in endemic areas should be carried out using hydatid cyst fluid of E. granulosus prepared from cysts in either sheep, human or mouse for immunoblot and from sheep or mouse for ELISA, (2) both primary screening and confirmation of AE in endemic areas should be carried out using Em18-ELISA, Em18-immunoblot or Em2(plus)-ELISA. Serodiagnosis in areas where both AE and CE are endemic, such as in China, should be carried out as a combination of (1) and (2), and (3) serology of NCC should be carried out using GP-ELISA or GP-immunoblot. All samples showing antibody to Em18 are exclusively from echinococcosis cases. There have been no false positive test reactions with sera from other diseases. Strongest Em18 responders are all from patients with AE but some weaker responses may be found in sera of persons with advanced complex lesions of CE. These highly reliable serodiagnostic methods using native, recombinant and synthetic antigens are briefly summarized and experiences with these methods in Japan is reviewed. We believe that use of these specific antigens in screening and confirmation programs for AE in Japan will improve specificity and reduce the confusion, anxiety and expense in persons whose sera give false positive reactions with crude echinococcal antigens.     

Immunoblot analysis of a 10 kDa antigen in cyst fluid of Taenia solium metacestodes

The diagnostic value of a 10 kDa subunit of 150 kDa protein in cyst fluid (CF) of Taenia solium metacestodes was evaluated. Immunoblot analysis revealed that most sera from patients with neurocysticercosis recognized the 10 kDa subunit strongly (209/217 cases, 84.6%), while a few sera from individuals with other parasitic diseases including alveolar echinococcosis (AE, 2/20, 10%) and cystic echinococcosis (CE, 2/25, 8%) showed faint reactions. Sera of cases with other parasitic diseases, especially AE and CE, exhibited cross reactions against other bands in CF. Both differential immunoblot and immunoprecipitation analyses showed that the 10 kDa subunit was the most specific to cysticercosis and highly antigenic, whereas other components at 20–40, 64, 95 and 106 kDa in CF were cross-reactive. IgG subclass ELISA and immunoblot demonstrated that both IgG4 and IgG1 reactions were predominant in neurocysticercosis and recognized the 10 kDa .     

快速诊断多房棘球蚴病胶体金免疫层析试条方法的建立与评价

目的建立快速、简便诊断多房棘球蚴病的胶体金免疫层析试条方法。方法提取多房棘球蚴原头节总RNA,通过RT-PCR获得编码Em18基因片段并克隆入pGEX-3X表达载体,异丙基-β-D-硫代半乳糖苷(IPTG)诱导表达得到重组蛋白;采用柠檬酸三钠还原法制备胶体金,标记抗人IgG单克隆抗体;将重组Em18抗原包被于硝酸纤维素膜适当位置,制成检测特异抗体的胶体金免疫层析试条。用该试条检测多房棘球蚴病(56份)、细粒棘球蚴病(87份)、囊尾蚴病(30份)、日本血吸虫病(10份)和弓形虫病(10份)患者血清,以及健康人(50份)血清,以评价其检测的敏感性和特异性,同时用ELISA法进行平行检测,以评价该试条的诊断性能。结果以重组蛋白Em18为抗原胶体金免疫层析试条检测多房棘球蚴病患者血清,敏感性为92.9%(52/56)。与细粒棘球蚴病和囊尾蚴病患者血清分别存在9.2%(8/87)和3.3%(1/30)的交叉反应,与健康人血清存在8.0%(4/50)的假阳性率,与日本血吸虫病和弓形虫病患者血清则无交叉反应,特异性为93.0%(174/187)。ELISA法检测的敏感性和特异性分别为94.6%(54/56)和92%(172/187),与试条法比较两者差异均无统计学意义(P>0.05)。kappa分析结果显示,试条法与ELISA法检测多房棘球蚴病患者血清的结果高度一致(κ=0.98)。结论以重组Em18抗原建立的快速诊断胶体金免疫层析试条,检测多房棘球蚴病的敏感性和特异性均较高。     

western blot 法诊断囊虫病的应用研究

目的：探讨四种猪囊尾蚴（Ｃｙｓｔｉｃｅｒｃｕｓｃｅｌｕｌｏｓａｅ）特异性抗原ｃＣ１、ｃＣ２、ｃＰ１、ｃＨ１（分子量分别为２８ｋＤａ、１８ｋＤａ、１４ｋＤａ、３４ｋＤａ）混合应用诊断人囊虫病的价值。方法：以猪囊尾蚴ｃＤＮＡ表达文库中筛选出的β－半乳糖苷酶－猪囊虫特异性抗原ｃＤＮＡ编码的融合蛋白（ｆｕｓｉｏｎｐｒｏｔｅｉｎｓ，ＦＰ）为抗原，作简化的Ｗｅｓｔｅｒｎｂｌｏｔ（ｉｍｐｒｏｖｅｄＷｅｓｔｅｒｎｂｌｏｔ，ＩＷＢ）分析，检测１０７例囊虫病、４０例华支睾吸虫病、２４例包虫病和３４例健康人血清对融合蛋白的反应。同时应用粗制抗原（ｃｒｕｄｅａｎｔｉ－ｇｅｎ，ＣＡ）进行ＥＬＩＳＡ、ＩＨＡ对比检测。结果：在简化Ｗｅｓｔｅｒｎｂｌｏｔ检测中，ＦＰ被１０７例囊虫病患者血清中９４例（８７．９％）血清所识别，与华支睾吸虫病、包虫病患者及健康人血清无交叉反应，特异性为１００％。以粗制抗原作ＥＬＩＳＡ、ＩＨＡ检测囊虫病人血清中的ＩｇＧ抗体阳性率分别为８４．１％和７４．８％，与华支睾吸虫病患者血清存在交叉反应，假阳性率分别为２．５％、１２．５％；与包虫病患者血清存在交叉反应，假阳性率分别为８．３％、１６．７％；与健康人血清也存在交叉反应, 假阳性率分别为8. 8%、11. 8% 。结论: β－半乳糖苷酶2猪囊尾蚴FP 诊断囊虫病具有较高敏感性和高度的特异性。     

Negative-ELISA using native and filtrated cystic fluid antigens to rule out cystic echinococcosis

An increasing number of cases of echinococcosis in Thailand have been imported, probably native infections and medical transfers. Serodiagnosis is one diagnostic choice for interpreting infections before a further step is done. Due to limited antigen, indirect ELISA has been used as a negative screening test for IgG-detection to rule out echinococcosis. Native hydatid cystic fluid (HCF) antigen from Belgium was used for such testing, in which the ODs-ELISA of samples were compared with those of two positive controls. Subsequently, hydatid cyst fluid from a Thai patient was obtained and the filtrated cyst fluid antigen [(<30)-(>10) kDa, HCF30.10] was prepared to develop negative screening results for the serum samples. By using HCF, three of twenty-four samples resulted in higher ODs-ELISA than the controls. In an attempt to observe the cross-reactivity of this native antigen, IgG-antibodies from many helminthiases cross-reacted and showed high ODs-ELISA. The HCF30.10 Ag was used to develop the test and analyze IgG-antibodies from 5 positive controls (2 parasite-confirmed and 3 positive-serodiagnosed), 183 heterologous cases of 29 diseases and 50 healthy control sera. At a cut-off value of 0.484, the test had 100% sensitivity and 42% specificity. Only Malayan filariasis, onchocercosis, fascioliasis, amebiasis, giardiasis and blastocystosis gave true negatives. Antibodies from nematodiases strongly cross-reacted with HCF30.10 Ag. Nine of fifty (18%) healthy serum controls produced higher OD-values than the cut-off. The routine ELISA uses the HCF30.10 Ag to produce a negative result to echinococcosis, because limited cystic fluid antigen (Thai patient) for test improvement, a lot of cross-reactions and only two protoscolex-positive controls are available.     

细粒棘球绦虫转酮醇酶克隆 表达及免疫性分析

目的 通过原核表达获得细粒棘球绦虫转酮醇酶（TK）表达产物,分析其作为棘球蚴病诊断抗原分子的价值。方法 PCR扩增TK基因,克隆至原核载体pMD19?EgTK,随后亚克隆至表达载体pET?28a,构建目的基因TK原核表达质粒pET?28a（+）?EgTK,转入大肠埃希菌BL21,分离纯化蛋白,经SDS?PAGE、Western blotting鉴定后,收集细粒棘球蚴病（CE组）、多房棘球蚴病（AE组）患者及健康人（健康组）血清,以酶联免疫吸附试验（ELISA）检测重组蛋白作为诊断抗原的价值。结果 成功构建pET?28a（+）?EgTK质粒,经SDS?PAGE和Western blotting分析,EgTK蛋白在70 kDa处出现条带,与理论值一致。ELISA显示,CE组、AE组和健康组血清反应吸光度A450值间差异有统计学意义（F = 44.47,P < 0.01）,CE组（1.46±0.41）、AE组A450值（1.28±0.29）高于健康组（0.66±0.23）（P ＜ 0.05）,但CE组和AE组间A450值差异无统计学意义（P＞ 0.05）。结论 重组TK分子可较好地区分棘球蚴病患者和非棘球蚴病患者,但无法区分细粒棘球蚴病和多房棘球蚴病患者。