Two nanobody‑based immunoassays to differentiate antibodies against genotype 1 and 2 porcine reproductive and respiratory syndrome virus  

作　　者：Xu Chen Yueting Chang Lu Zhang Xinyu Zhao Zhihan Li Zhijie Zhang Pinpin Ji Qingyuan Liu Jiakai Zhao Jiahong Zhu Baoyuan Liu Xinjie Wang Yani Sun Qin Zhao 

机构地区：[1]Department of Preventive Veterinary Medicine,College of Veterinary Medicine,Northwest A&F University,Yangling,Shaanxi 712100,China [2]Shenzhen Branch,Guangdong Laboratory of Lingnan Modern Agriculture,Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs,Agricultural Genomics Institute at Shenzhen,Chinese Academy of Agricultural Sciences,Shenzhen 518100,China

出　　处：《Animal Diseases》2024年第2期98-114,共17页动物疾病（英文）

基　　金：funded by grants from the National Key R&D Program of China(2023YFD1800304);the National Natural Science Foundation of China to QZ(32273041);the Natural Science Foundation of Shaanxi Province of China(2022JC-12);the Central Public-interest Scientific Institution Basal Research Fund,National Data Center of Animal Health.

摘　　要：Porcine reproductive and respiratory syndrome virus(PRRSV)infection causes significant economic loss to the global pig industry.Genotype 1 and 2 PRRSV(PRRSV-1 and-2)infections have been reported in China,Europe and America.For accurate prevention,nanobodies were first used as diagnostic reagents for PRRSV typing.In this study three nanobodies targeting both PRRSV-1 and-2,two targeting PRRSV-1 and three targeting PRRSV-2,were screened and produced.To develop two competitive ELISAs(cELISAs),the g1-2-PRRSV-Nb3-HRP nanobody was chosen for the g1-2-cELISA,to detect common antibodies against PRRSV-1 and-2,and the g1-PRRSV-Nb136-HRP nanobody was chosen for the g1-cELISA,to detect anti-PRRSV-1 antibodies.The two cELISAs were developed using PRRSV-1-N protein as coating antigen,and the amounts for both were 100 ng/well.The optimized dilution of testing pig sera was 1:20,the optimized reaction times were 30 min,and the colorimetric reaction times were 15 min.Then,the cut-off values of the g1-2-cELISA and g1-cELISA were 26.6%and 35.6%,respectively.Both of them have high sensitivity,strong specificity,good repeatability,and stability.In addition,for the 1534 clinical pig sera,an agreement rate of 99.02%(Kappa values=0.97)was determined between the g1-2-cELISA and the commercial IDEXX ELISA kit.For the g1-cELSIA,it can specifically detect anti-PRRSV-1 antibodies in the clinical pig sera.Importantly,combining two nanobody-based cELISAs can differentially detect antibodies against PRRSV-1 and-2.

关 键 词：PRRSV Competitive ELISA NANOBODY Antigen epitope 

分 类 号：S85[农业科学—兽医学]