Nanobodies against African swine fever virus p72 and CD2v proteins as reagents for developing two cELISAs to detect viral antibodies  

作　　者：Jiahong Zhu Qingyuan Liu Liuya Li Runyu Zhang Yueting Chang Jiakai Zhao Siyu Liu Xinyu Zhao Xu Chen Yani Sun Qin Zhao 

机构地区：[1]Department of Preventive Veterinary Medicine,College of Veterinary Medicine,Northwest A&F University,Yangling Observing and Experimental Station of National Data Center of Animal Health,Ministry of Agriculture,Yangling,712100,China

出　　处：《Virologica Sinica》2024年第3期478-489,共12页中国病毒学（英文版）

基　　金：supported by the Natural Science Foundation of China(grant no.32273041);the Natural Science Foundation of Shaanxi Province of China(grant no.2022JC-12);the Key R&D Program of Shaanxi Province(grant no.S2022-YF-YBNY-0673);the Central Public-interest Scientific Institution Basal Research Fund.

摘　　要：African swine fever virus(ASFV)poses a significant threat to the global swine industry.Currently,there are no effective vaccines or treatments available to combat ASFV infection in pigs.The primary means of controlling the spread of the disease is through rapid detection and subsequent elimination of infected pig.Recently,a lower virulent ASFV isolate with a deleted EP402R gene(CD2v-deleted)has been reported in China,which further complicates the control of ASFV infection in pig farms.Furthermore,an EP402R-deleted ASFV variant has been developed as a potential live attenuated vaccine candidate strain.Therefore,it is crucial to develop detection methods that can distinguish wild-type and EP402R-deleted ASFV infections.In this study,two recombinant ASFV-p72 and-CD2v proteins were expressed using a prokaryotic system and used to immunize Bactrian camels.Subsequently,eight nanobodies against ASFV-p72 and ten nanobodies against ASFV-CD2v were screened.Following the production of these nanobodies with horse radish peroxidase(HRP)fusion proteins,the ASFV-p72-Nb2-HRP and ASFV-CD2v-Nb22-HRP fusions were selected for the development of two competitive ELISAs(cELISAs)to detect anti-ASFV antibodies.The two cELISAs exhibited high sensitivity,good specificity,repeatability,and stability.The coincidence rate between the two cELISAs and commercial ELISA kits was 98.6%and 97.6%,respectively.Collectively,the two cELISA for detecting antibodies against ASFV demonstrated ease of operation,a low cost,and a simple production process.The two cELISAs could determine whether pigs were infected with wild-type or CD2v-deleted ASFV,and could play an important role in monitoring ASFV infections in pig farms.

关 键 词：African swine fever virus(ASFV) ASFV-p72 ASFV-CD2v Nanobody-HRP Competitive ELISA 

分 类 号：S852.651[农业科学—基础兽医学]