Preparation Of Monoclonal Antibodies Against Porcine Epidemic Diarrhea Virus SHpd/201 And Identification Of Protein S' Epitope

PED is a highly contagious and infectious disease of piglets with diarrhea caused by PEDV.In recent years,due to the variation of PEDV strains,the original vaccine prevention and control effects are affected.The prevention and control of the disease put forward higher requirements.However,the pathogenic mechanism of the new epidemic strains is not clear,the lack of efficient and specific diagnostic methods,it is urgent need to carry out basic and applied research.In the research,PEDV were purified.We achieved to get MAbs named F1-D6?F21-D5?F21-F3?F21-F5?F31-D3?F31-D6?F31-F3?F31-F5?F31-G3?F31-G4?F42-C6?F51-F4?F51-G4 by the methods of IFA,ELISA and Western blot.3?F31-D3?F31-F3?F1-D6?of them can specifically recognize protein N,and 1?F42-C6?for protein S.Protein S is an important structural protein of PEDV,which contains both the receptor binding domain of the host cells and neutralizing epitopes of the virus.Therefore,we chose MAb F42-C6 to identify its epitope.The overlapping fusion proteins S11,S12,S13,S21 and S22were expressed with the template of SHpd/2012 strains,the results showed that F42-C6 can specifically recognize the truncated protein of S13.The S13 fusion protein was further truncated expression by pinpointing its epitope,results showed that the epitope of the smallest functional domain of F42-C6 S was:S ⁷⁰⁶AYVDDD⁷¹¹.A specific analysis of the epitope concluded that the epitope was relatively conservative among different PEDV classic strains,and the difference between the PEDV popular strains was absolutely conservative.Through the above research,it provides an effective tool for the establishment of PEDV diagnostic methods and antigen characteristics,and lays the foundation for the study of the pathogenesis of the disease in the future.