旋毛虫Ts21重组蛋白的免疫诊断价值及免疫保护作用的研究

目的 探讨旋毛虫Ts21重组蛋白的免疫诊断价值及免疫保护作用。 方法 应用旋毛虫Ts21重组蛋白ELISA（Ts21-LISA）与肌幼虫ES抗原ELISA（ES-LISA）对旋毛虫病与其他寄生虫病患者血清及5种旋毛虫（T1、T2、T3、T4和T7）感染小鼠血清进行检测,并观察不同剂量旋毛虫感染小鼠后不同时间的血清抗体水平。将Ts21重组蛋白皮下注射免疫小鼠（20 μg/只,免疫3次,每次间隔10 d）,末次免疫后10 d,每只小鼠用300条旋毛虫肌幼虫经口攻击感染,3.5 d和42 d 后剖杀,观察肠道成虫与肌幼虫数并计算减虫率。 结果 Ts21-LISA检测旋毛虫病、并殖吸虫病、囊尾蚴病及棘球蚴病患者血清的抗体阳性率分别为94.7%（18/19）、15.8%（3/19）、9.1%（1/11）和7.7%（1/13）,与血吸虫病、华支睾吸虫病患者血清及健康人血清无交叉反应;Ts21重组蛋白与ES抗原ELISA检测旋毛虫病患者血清抗体的敏感性与特异性差异均无统计学意义（χ²=0,P＞0.05;χ²=0.358,P＞0.05）。Ts21重组蛋白与ES抗原检测T1感染小鼠血清的敏感性差异无统计学意义（χ²=0.104,P＞0.05）,与T2、T3、T4、T7感染小鼠血清的交叉反应率明显低于ES抗原（χ²=17.069,P＜0.05）。小鼠感染300条旋毛虫后4 周,应用Ts21-LISA检测的血清抗体阳性率为100%（10/10）;小鼠感染5条旋毛虫后6周,血清抗体阳性率为100%（10/10）。Ts21重组蛋白免疫小鼠用旋毛虫攻击感染后3.5 d和42 d,肠道成虫与肌幼虫减虫率分别为42.71%和49.8%。 结论 Ts21重组蛋白可用于旋毛虫病的血清学检测,但不能忽视与并殖吸虫病、囊尾蚴病及棘球蚴病患者血清的交叉反应。     

建立和评价ELISA法检测血清和唾液中旋毛虫IgG抗体的研究

目的 建立检测血清和唾液中旋毛虫抗体的酶联免疫吸附试验(ELISA)方法.方法 应用方阵滴定法,筛选适宜的旋毛虫抗原(肌肉幼虫可溶性抗原、肌肉幼虫排泄分泌抗原、成虫可溶性抗原、成虫排泄分泌抗原)浓度、血清和唾液稀释度、辣根过氧化物酶标记的山羊抗兔、山羊抗人IgG抗体稀释度.共有20份旋毛虫感染兔、10份旋毛虫病患者血清和唾液用于这4种抗原的敏感性试验,20份健康兔与38份其他寄生虫感染兔和患者的血清和唾液用于这4种抗原的特异性试验.结果 这4种抗原适宜包被浓度依次为8.0 μg/ml、6.0 μg/ml、10.0 μg/ml、9.0 μg/ml.适宜的血清稀释度依次为1:100、1:200、1:50、1:200,唾液均用原液.适宜的山羊抗兔、山羊抗人IgG稀释度分别为1:2 500和l:2 000.这4种抗原检测旋毛虫感染兔血清和唾液的敏感性分别为100%和80%~100%,检测旋毛虫病患者血清和唾液的敏感性分别为100%和60%~80%;检测血清和唾液的特异性依次为81.03%、89.65%、77.59%、82.76%和93.10%、96.55%、89.65%、91.35%.结论 建立了检测兔和人血清及唾液中旋毛虫lgG抗体的ELISA方法.当采集血清标本有困难时,可将唾液替代血清用于检测旋毛虫病.     

应用斑点免疫金渗滤法检测旋毛虫病患者血清IgG

目的　研究应用斑点免疫金渗滤法(DIGFA)快速检测旋毛虫病患者血清抗旋毛虫IgG抗体。　方法　采用旋毛虫肌肉期幼虫膜抗原,以胶体金颗粒结合的羊抗人IgG为标记抗体,以颜色深浅为判断阳性标准。　结果　纯化的旋毛虫肌肉期幼虫膜抗原与患者血清中特异性抗旋毛虫IgG抗体通过渗滤在硝酸纤维素膜上反应,10min内即可直接观察结果。在76份患者血清的检测中,阳性率为94.74%,与ELISA法的检出阳性率86.84%相比差异无显著性(χ2=2.83,P>0.05)。交叉试验与重复试验结果显示DIGFA具有较好的特异性及稳定性。　结论　DIGFA法可快速检测旋毛虫病患者血清特异性旋毛虫IgG抗体     

小鼠实验感染不同种旋毛虫后血清IgG抗体水平的变化

目的观察小鼠感染不同种旋毛虫后血清IgG抗体水平的变化。方法将50只小鼠随机分成5组（每组10只），分别感染旋毛虫（T1）、乡土旋毛虫（T2）、布氏旋毛虫（T3）、伪旋毛虫（T4）及纳氏旋毛虫（T7），每只感染300条幼虫，感染后1～6周每周尾部静脉采血，6周后每2周尾部静脉采血，至感染后20周，用旋毛虫肌幼虫ES抗原ELISA检测血清中抗旋毛虫IgG抗体水平。结果小鼠感染旋毛虫、乡土旋毛虫、布氏旋毛虫及纳氏旋毛虫后3～5周，血清IgG抗体水平快速升高，至感染后第8周达高峰，此后旋毛虫和乡土旋毛虫感染小鼠的血清IgG抗体水平缓慢下降，布氏旋毛虫及纳氏旋毛虫感染小鼠的血清IgG抗体水平迅速下降；小鼠感染伪旋毛虫后3～5周血清IgG抗体水平快速升高，至第16周达高峰，之后缓慢下降。5种旋毛虫感染小鼠的血清IgG抗体水平差异具有显著性（P〈0．05）。结论5种旋毛虫感染小鼠的血清IgG抗体水平和动态变化不同；旋毛虫肌幼虫ES抗原可用于其他4种旋毛虫（乡土旋毛虫、布氏旋毛虫、伪旋毛虫、纳氏旋毛虫）感染的血清学诊断及流行病学调查。     

肌幼虫可溶性抗原与ES抗原检测抗旋毛虫抗体效果的比较

目的比较旋毛虫肌幼虫可溶性抗原(SAg)与ES抗原(ESAg)检测抗旋毛虫抗体的效果。方法应用SAg-ELISA和ESAg-ELISA对旋毛虫病患者血清、感染旋毛虫的小鼠血清及肉汁、其他寄生虫感染人及动物血清进行抗旋毛虫抗体的检测。结果SAg-ELISA和ESAg-ELISA对10例旋毛虫病患者血清检测时抗体阳性率均为100%,但对10份正常人血清检测时SAg-ELISA的背景较深,两种抗原的A值相比较具有显著性差异(P<0.05);应用两种抗原对旋毛虫感染小鼠和正常小鼠血清及肉汁的检测结果与对人血清的检测结果相似。SAg与肝吸虫、肺吸虫、血吸虫等寄生虫感染人及动物血清均有交叉反应,而ESAg仅与1例肺吸虫病患者血清有交叉反应。结论旋毛虫肌幼虫SAg和ESAg检测抗旋毛虫抗体的敏感性相同,但ESAg的特异性优于SAg;肉汁也可作为样本进行抗旋毛虫抗体的检测。     

检测唾液中特异性抗体诊断人体旋毛虫病的研究

目的探讨检测唾液特异性抗体对人体旋毛虫病的诊断价值。方法用ELISA测定57例旋毛虫病人唾液中旋毛虫IgG抗体,并与血清同种抗体检测结果进行比较。结果检测唾液中旋毛虫IgG抗体诊断旋毛虫病的敏感性为64.91%,特异性为100%;检测血清旋毛虫IgG抗体诊断旋毛虫病的敏感性和特异性分别为91.23%和95.83%;唾液旋毛虫IgG与血清旋毛虫IgG的OD值呈正相关(r=0.4011)。结论检测唾液中特异性抗体对于诊断人体旋毛虫病有一定的应用价值,在采集血清有困难时可将唾液作为血清的替代检测标本。     

应用BA-Dot-ELISA检测旋毛虫血清抗体的研究

以旋毛虫肌幼虫层析抗原及国产BA试剂,建立了快速检验旋毛虫病的生物素亲和素酶免疫斑点法(BA-Dot-ELISA)。用此法和Dot-ELISA、PPA-ELISA同时检测15份旋毛虫病人血清,阳性率分别为100％、93.3％和93.3％,检测417份非旋毛虫病人血清,均为阴性。用三种方法检测30份实验感染猪阳性血清,BA-Dot-ELISA敏感性分别为PPA-ELISA和Dot-ELISA的7.13倍和2.70倍。本法与血吸虫病、囊虫病、弓形虫感染者无交叉反应。表明本法对旋毛虫有较高的特异性和敏感性,有助于低水平血清抗体旋毛虫病的检测,适于早期诊断,流行病学调查及动物的宰前检查。     

胶体金免疫层析法检测广州管圆线虫感染小鼠血清特异性抗体的研究

目的建立一种无需仪器、操作简单,具较好敏感性和特异性的适用于基层快速检测广州管网线虫感染的胶体金免疫层析方法。方法将重组广州管圆线虫五期幼虫抗原Acll蛋白为检测点膜抗原,羊抗兔IgG喷涂存质控线,与胶体金标记兔抗小鼠单抗组装成广州管圆线虫胶体金免疫层析法检测试剂条,用于检测阳性小鼠血清特异性抗体。试验设阴性小鼠血清为对照。结果确定试剂条的检测条件为：检测线重组抗原Acll用量为4mg／mI（喷量1μl／cm）,质控线羊抗兔IgG用量为1．87mg／ml（喷量1 μl／cm）,胶体金标记兔抗小鼠单抗采用吸光度（A）值为5的喷涂世（喷量2 μl／cm）。用该方法检测小鼠血清抗广州管线虫抗体,其敏感性为100％（10／10）,特异性为100％（10／10）。结论胶体金免疫层析法检测广州管圆线虫抗体具有较好的敏感性和特异性,经进一步完善后有望用于广州管网线虫病的临床快速筛查和流行病学调查。     

IEST检测感染犬弓首线虫幼虫鼠血清抗体的研究

用感染犬弓首线虫幼虫鼠肝石蜡切片作为抗原片进行免疫酶染色试验（IEST），检测30份犬弓首线虫幼虫感染鼠血清抗体（IgG），阳性率为96.67％。12份旋毛虫感染鼠血清及12份健康鼠血清抗体均为阴性，结果表明本法的敏感性和特异性均较高。     

Ts21基因在旋毛虫不同期虫体的表达及特性的研究

目的观察旋毛虫Ts21基因在不同发育期虫体的表达及其特性。方法应用RT-PCR检测旋毛虫Ts21基因在成虫、新生幼虫、感染后15d的成囊前幼虫及感染后42d的成囊幼虫(肌幼虫)的转录情况;应用抗Ts21重组蛋白血清通过间接荧光抗体试验(IFA)对成囊前幼虫及肌幼虫冰冻切片抗原进行检测。应用抗Ts21重组蛋白血清对旋毛虫肌幼虫粗(可溶性)抗原及排泄分泌(ES)抗原进行Western-blot分析。结果RT-PCR发现旋毛虫成虫与感染后42d肌幼虫均扩增出一条分子量约540bp的特异性条带(Ts21基因目的条带),而新生幼虫与感染后15d成囊前幼虫则未扩增出目的条带;IFA结果表明抗Ts21重组蛋白血清只与感染后42d成囊幼虫抗原发生阳性反应,而不与感染后15d的成囊前幼虫抗原发生阳性反应。Western-blot结果显示抗Ts21重组蛋白血清只与旋毛虫肌幼虫粗抗原和ES抗原中Mr 21 000的单一蛋白条带发生阳性反应。结论旋毛虫Ts21基因的表达具有期特异性,Ts21蛋白是旋毛虫肌幼虫ES抗原中的一部分。     

The usefulness of ELISA test for early serological detection of Trichinella spp. infection in pigs

Trichinellosis is a parasitic zoonosis transmitted to humans through consumption of raw or undercooked meat from animals infected with nematodes of the Trichinella genus. Every year seropositive cases are found among the human population and thus trichinellosis still remains an epidemiologically important disease. The first step of the study was the optimization of a new ELISA method enabling an early and specific serological diagnosis of trichinellosis in pigs and wild boars using excretory-secretory (ES) antigens obtained from in vitro cultures of L1 T. spiralis. Serum samples were assayed for anti-T. spiralis IgG antibodies using the new ELISA protocol and a reference test--Standard manufactured by Institut Pourquier. The optimization involved the selection of suitable plates for antigen coating, dilution of sera and antibodies and their time of incubation. On the basis of the optimization a new ELISA procedure for the detection of IgG and IgM against T. spiralis was elaborated. Conventional, Iberian pigs and SPF (Specific Pathogen Free) pigs were infected with 200, 1000 and 20,000 muscle larvae of T. spiralis. Serum samples were obtained at 5 and 1 dbi (day before infection), and 5, 10, 15, 20, 25, 30, 40, 50, 60 dpi (day post infection) and screened for specific IgG antibodies against excretory-secretory L1 T. spiralis antigens. Serum samples were obtained from the EU project Trichiporse: "Safe pork and horse meat on EU markets: early and unbiased diagnostic tests for Trichinella". Field samples of conventional pigs (1474) and wild boars (1784) were obtained from slaughter houses in different parts of Poland. Pigs were examined for the presence of Trichinella spp. using the artificial digestion method. Only four pigs were naturally infected with T. spiralis, the remaining were Trichinella larvae free. ELISA was used to examine IgG levels against L1 T. spiralis in pig and wild boar sera. The usefulness of ELISA for anti-IgG detection in pigs is usually limited by the nature of the antigen. The antigens were prepared in different laboratories: in Germany--Ag ES L1 T. spiralis (N), Italy--Ag ES L1 T. spiralis (W)) and in Poland--Ag ES L1 T. spiralis. Cut-off values for ELISA along with the estimated sensitivity and specificity were calculated using different methods: S/P%, M+3SD and ROC (Receiver Operating Characteristic). In SPF and Iberian pigs inoculated with 200, 1000 and 20,000 L1 T. spiralis, specific antibodies were detected 40, 30 and 25 dpi, respectively, with the use of the Standard (reference test). The analysis of the two ELISA procedures demonstrated a high sensitivity and specificity for the newly elaborated test utilizing the Ag ES L1 T. spiralis. In conventional pigs infected with 20,000 L1 T. spiralis specific antibodies were detected from 20 dpi when employing the new protocol. Similar results for the Standard and new ELISA test were obtained for serum samples of conventional pigs infected with 200 and 1000 larvae, which became positive from 40 dpi and 30 dpi, respectively. The results showed that both: the Standard and new protocols were comparable, and based on this, the new test was applied for further research. Results obtained adopting the new protocol with three antigens showed that two of them: Ag ES L1 T. spiralis (W) and Ag ES L1 T. spiralis are similar. The specific IgG antibodies for infective doses of 200 and 1000 larvae for these antigens were detectable 40 and 30 dpi respectively. In pigs infected with the highest dose of T. spiralis larvae IgG antibodies were detectable from 20 dpi when Ag ES L1 T. spiralis was used. These results strongly indicate that in examined pigs, the specific IgG response to T. spiralis infection is dose dependant. Of 1474 examined pig sera only 0.99% gave a positive signal against ES L1 T. spiralis antigen. Of 1784 examined wild boars sera only 0.68 % gave positive results using the new ELISA protocol. ELISA is a useful method for detecting specific IgG antibodies in pigs experimentally infected with different doses of T. spiralis and naturally infected pigs. In pigs the specific IgG response is dose dependant. The Ag ES L1 T. spiralis increases the specifity of the method and reduces false positive results. Simultaneous use of both methods: digestion and ELISA for the diagnosis of Trichinella in naturally infected pigs and wild boars may increase the chances of eliminating meat infected with T. spiralis larvae.     

The influence of the procedure of excretory-secretory L1 trichinella spiralis antigen preparation on the efficiency of an ELISA test in pigs

BACKGROUND: Trichinellosis is a parasitic zoonosis transmitted to humans by consumption of raw or undercooked meat from animals infected by worms of the Trichinella genus. Every year seropositive cases are found among the human population and thus trichinellosis still remains an epidemiologically important disease in Poland. The usefulness of ELISA for anti-T. spiralis IgG detection in pigs is still limited by the nature of antigen. The objective in the present study was to compare the usefulness of excretory-secretory antigens of L1 T. spiralis for the serological detection of IgG antibodies in pigs. MATERIAL AND METHODS: The antigens were prepared in different laboratories: Ag ES L1 T. spiralis (N) in Germany, Ag ES L1 T. spiralis (W) in Italy and Ag ES L1 T. spiralis in Poland. Conventional, Iberian pigs were infected with 200, 1000 and 20 000 muscle larvae of T. spiralis. Serum samples were obtained at 5 and 1 dbi (day before infection), and 5, 10, 15, 20, 25, 30, 40, 50, 60 dpi (day post infection) and screened for specific IgG antibodies to excretory-secretory L1 T. spiralis antigens. Serum samples were obtained from the EU project TRICHIPORSE. The cut-off value of ELISA was determined on serum samples from 248 Trichinella-free pigs from Poznaii and Boza Wola, that were examined by artificial digestion. RESULTS: In pigs infected with 200 L1 T. spiralis larvae, specific IgG were detectable from 50 dpi, when the Ag ES L1 T. spiralis (N) was used, whereas when Ag ES L1 T. spiralis (W) and Ag ES L1 T. spiralis were used, the specific IgG were detectable from 40 dpi. In pigs infected with 1000 LI T. spiralis larvae, specific IgG was observed from 30 dpi when Ag ES L1 T. spiralis (W) and Ag ES L1 T. spiralis were used, but when Ag ES L1 T. spiralis (N) was used specific IgG were detectable from 40 dpi. In the group infected with the highest dose of T. spiralis larvae, specific IgG were detectable from 30 dpi when Ag ES L1 T. spiralis (N) and Ag ES L1 T. spiralis (W) were used, whereas when Ag ES L1 T. spiralis was used specific IgG were detectable from 20 dpi. The results strongly indicated that in the examined pigs, the specific IgG response against T. spiralis infection is dose dependent. Furthermore, it was shown that the high infectious dose induced earlier increasing of specific IgG response. Statistical analysis revealed a significant positive correlation between OD values obtained in procedures based on the three antigens. The results were statistically repeatable for procedures and for single pigs (P<0.01).     

Sandwich ELISA detection of excretory-secretory antigens of Toxocara canis larvae using a specific monoclonal antibody

We produced a new monoclonal antibody (mAb) to the excretory-secretory (ES) antigens of Toxocara canis larvae. The mAb (IgG1) reacts specifically with the 120 kDa protein of many ES molecules and does not have any cross-reactivity with adult T. canis antigens. Sandwich ELISA to detect the ES antigens was performed using the mAb and rabbit polyclonal antiserum. The lower limit for the detection of ES antigen was 4 ng/ml; assay was proportional within a concentration range of 4 ng/ml to 1 microg/ml of ES antigen. This assay system may prove valuable when seeking to quantify parasite burden early in infection and when determining the efficacy of anthelmintic treatment.     

旋毛虫新生幼虫期特异性T668 cDNA在大肠埃希菌中的表达及鉴定

目的对旋毛虫新生幼虫期特异性T668cDNA进行表达及鉴定,以获得基因工程抗原。方法应用PCR技术,从pBK CMV T668重组质粒中扩增到不含信号肽序列的T668cDNA片段,将目的基因克隆于原核表达载体pET28a(+),构建pETT668重组质粒,再将其转化到E.coli表达菌株DE3感受态细胞中,经IPTG诱导表达,以SDS PAGE鉴定表达产物。结果pETT668表达蛋白的分子质量单位为49ku,且随诱导时间的延长蛋白表达量逐渐增加,诱导5h时表达量达到高峰;薄层扫描结果显示,目的蛋白占菌体总蛋白的34.6%。Western blotting检测显示,表达蛋白可被感染旋毛虫家猪血清所识别。结论旋毛虫新生幼虫期特异性T668基因在大肠埃希菌中获得高效表达,且表达蛋白具有良好的抗原性。     

Characterization of a Trichinella spiralis 31 kDa protein and its potential application for the serodiagnosis of trichinellosis

The Trichinella spiralis 31 kDa protein (Ts31) was screened from the excretory-secretory (ES) proteins of muscle larvae (ML) by immunoproteomics using serum from mice infected with T. spiralis at 18 days post infection (dpi). The aim of this study was to characterize the Ts31 protein and to evaluate the potential of the recombinant Ts31 protein (rTs31) for serodiagnosis of human trichinellosis. Ts31 gene was cloned and rTs31 was produced in an E. coli expression system. An anti-rTs31serum recognized the native protein migrating in a 25–55 kDa range by Western blotting of ML crude or ES antigens. Expression of Ts31 gene was observed at all developmental stages of T. spiralis (adult worms, newborn larvae, pre-encapsulated larvae and ML). An immunolocalization analysis identified Ts31 in the cuticle and stichocytes of the parasite. The sensitivity of rTs31-ELISA and ES antigen ELISA for detecting anti-Trichinella IgG antibodies in sera of patients with trichinellosis was 97.83% (45/46) and 86.78% (39/46), respectively (P > 0.05); The specificity of rTs31-ELISA was 99.13% (114/115), which was significantly higher than 85.22% (98/115) of ES antigen ELISA (P < 0.01). The rTs31 protein of T. spiralis could be considered as a potential diagnostic antigen for trichinellosis.     

弓形虫SAG1重组抗原的特征及其应用的研究

用昆虫细胞中表达的弓形虫主要表面抗原（SAGI）为试剂检测弓形虫IgG抗体。方法将昆虫细胞中表达的重组蛋白（rSAGI）通过单克隆抗体制备的亲和层析柱纯化．用纯化的rSAGI为抗原试剂检测弓形虫病血清，与其他试剂盒检测结果比较，然后再用免疫印迹试验确认．结果重组杆状病毒Bac304感染的Sf9细胞与空载bacmid感染的细胞比较，Bac304的SDS裂解物比空载株在SDS—PAGE考马斯亮蓝染色胶上明显多出一条带，分子量约为30kDa．在恒定条件下，分批收集Bac304感染的昆虫细胞，用免疫荧光鉴定，95％以上的细胞可被感染．在Balb／C小鼠中生产的抗SAGI的单抗XllA10C与Bac304的表达产物发生反应，用纯化的单抗与CNBr—Sepharose4B偶联制备的亲和层析柱从1．3X109感染Bac304的昆虫细胞裂解液中获得1．4mgrSAGI，以纯化rSAGI为抗原，采用EIA法检测了412份妇产科就诊者及不明原因淋巴结肿大等病人血清，检出弓形虫lgG抗体阳性13例，其中10例经全虫体蛋白印迹法确认为阳性．结论昆虫细胞表达的重组SAG1能识别人弓形虫病血清，可以用作诊断试剂．     

A case of Ascaris suum visceral larva migrans diagnosed by using A. suum larval excretory-secretory (ES) antigen

A 42-y-old female presented with common cold-like symptoms. Laboratory data showed mild liver dysfunction together with peripheral blood eosinophilia. She was suspected of having a helminthic infection, however parasite eggs or larvae were not detected by repeated stool examinations. Eventually she transpired to have a high IgG antibody titer against excretory-secretary (ES) antigen of Ascaris suum larvae, but not of Toxocara canis larvae, suggesting that she had been suffering from visceral larva migrans (VLM) caused by A. suum. Her sickness improved without any treatment. Current results clearly highlight the usefulness of ES antigens derived from larvae of A. suum for the fine discrimination of VLM caused by A. suum and by T. canis. Application of A. suum derived ES antigens as a diagnostic tool may reveal the distinctive clinical features of VLM caused by A. suum.     

猪鼻支原体vlp重复区融合蛋白的构建表达及反应原性分析

目的 猪鼻支原体(Mhr)是临床猪场常见病原菌之一,同时研究证实其与多种人类肿瘤有关。目前对Mhr的血清学检测尚无有效的方法。本研究以Mhr可变脂蛋白(vlp)家族为对象,设计vlp家族蛋白重复区片段融合蛋白,以作为检测用包被抗原使用。方法 根据大肠杆菌的密码子偏嗜性,设计并构建串联表达7种Mhr可变脂蛋白vlpA、B、C、D、E、F、G重复区片段的重组蛋白vlpA-G基因。将该基因片段装入pET-32a(+)载体中转化大肠杆菌,筛选鉴定获得阳性工程菌。IPTG诱导表达,镍柱亲和层析获得纯化的重组蛋白vlpA-G。Western Blot鉴定该重组蛋白与Mhr阳性血清的反应能力,并利用该重组蛋白为包被抗原初步建立间接ELISA方法用于检测猪血清中的Mhr抗体。结果 构建表达vlpA-G重组蛋白的基因工程菌,经PCR及DNA测序正确。IPTG诱导后出现明显蛋白条带,经镍柱亲和层析纯化获得vlpA-G重组蛋白。Western Blot试验证明重组蛋白vlpA-G能够和Mhr阳性兔血清产生明显的阳性杂交带;利用重组vlpA-G为包被抗原初步建立间接ELISA检测方法可成功检测Mhr阳性猪血清,证明该重组vlpA-G蛋白具有良好的反应原性。结论 本研究构建了重组蛋白vlpA-G并证实该蛋白具有良好的反应原性,可作为Mhr血清学诊断方法研究的候选抗原,同时也为Mhr重组蛋白疫苗提供可选抗原。