杆状病毒表达的猪传染性胃肠炎病毒钉状糖蛋白在其血清学诊断上的应用

The diagnostic application of recombinant transmissible gastroenteritis virus spike glycoprotein expressed in baculovirus expression system

利用从猪传染性胃肠炎病毒（ＴＧＥＶ）Ｍｉｌｅｒ株（Ｍ５Ｃ）克隆建立的一株重组杆状病毒（Ｒ２－２）表达的重组ＴＧＥＶ钉状糖蛋白（Ｓ），建立了一种阻断酶联免疫吸附试验（ＥＬＩＳＡ）来检测猪群抗ＴＧＥＶ抗体。试验表明，用重组病毒Ｒ２－２接种ｓｆ９细胞（ｓｐｏｄｏｐｔｅｒａｆｒｕｇｉｐｅｒｄａ）所表达的重组蛋白量在接种后第７２ｈ达到最高值；该重组蛋白能与抗ＴＧＥＶＳ蛋白Ａ位点的单克隆抗体特异性结合。用阻断ＥＬＩＳＡ检测６８份来自无ＴＧＥＶ感染或ＴＧＥＶ（Ｐｕｒｄｕｅｌ５）免疫的仔猪或母猪血清，结果与ＴＧＥＶ蚀斑减数试验完全相符，灵敏度和特异性均为１００％。同时检测来自ＴＧＥＶ试验免疫猪、美国部分地区猪群、我国进口猪以及我国国内猪群血清６２７份，阳性检出率分别为８２．６１％、６１．６２％、５８．３３％和２９．１０％；用中和试验（微量中和试验或病毒蚀斑减数试验）检测的ＴＧＥ血清抗体阳性率分别为８０．８７％、５９．６０％、５６．１１％和３０．６０％，两种方法对抗ＴＧＥＶ抗体的检出率没有显著差异。

The recombinant spike glycoprotein(s) of transmissible gastroenteritis virus of swine (TGEV) which was expressed by a recombinant baculovirus (R2 2) cloned from virulent TGEV Miller strain (M5C) and a blocking ELISA for TGEV antibody detection.The test showed that the recombinant protein expressed by R2 2 reached peak value 72 h after inoculation. The linkage of the protein and the monoclonal antibody against TGEV S protein site was confirmed.68 piglet or sow sera samples from pig farm where no TGE occurred and with negative results by periodical serological survey and from piglets or sows vaccinated with attenuated TGEV strain (purdue 115) were examined.The result was as the same as the Virus plaque reduction test,the sensitivity and the specificity were 100%.627 sera from TGE vaccination experiments,pig farms in some states in USA,imported breeding pigs and pig farms in China.The positive rate was 82.61%,61.61%,58.33% and 29.10% respectively.The virus neutralization test (microplate VN or plaque reduction test) also were run and the serological antibody positive rate were 80.87%,59.60%,56.10% and 30.60%, nespectively.There were no significant difference between the postive rate gotten from the blocking ELISA and VN test.