title: Truncated recombinant non-structural protein 2C-based indirect ELISA for FMD sero-surveillance.
abstract: Foot-and-mouth disease (FMD) is a transboundary animal disease caused by foot-and-mouth disease virus. In India, systematic preventive vaccination using inactivated trivalent (O, A and Asia 1) vaccine is the strategy being adopted to control FMD. The use of non-structural protein (NSP)-contaminated inactivated vaccine raises concerns over differentiation of infected and vaccinated animals (DIVA) by NSP based immunoassays. However, 2C being a membrane associated protein usually remain absent in vaccine formulations and thus, anti-2C response is one of the most reliable indicator of the FMDV infection. In this study, 34 amino acids from N-terminus of 2C protein were removed to eliminate membrane-binding amphipathic helicase activity for the expression of recombinant protein in soluble form. Truncated 2C (2Ct) was utilized for development of an indirect ELISA (I-ELISA) for bovine and the developed 2Ct I-ELISA was validated using a panel constituting of serum of naïve, vaccinated and infected animals. The assay was compared with the in-house r3AB3 I-ELISA and the overall concordance was 85.31%. The diagnostic sensitivity and specificity of the 2Ct I-ELISA were 92.9% and 94.0%, respectively. The apparent prevalence of anti-2C antibodies for random bovine samples tested by the developed assay was 23.7%. The developed ELISA will help in augmenting the sensitivity of detection if used in combination with r3AB3 I-ELISA for sero-surveillance.
authors.affiliation: Project Directorate on Foot and Mouth Disease, Indian Council of Agricultural Research, IVRI Campus, Mukteswar 263138, Uttarakhand, India.
authors.forename: Sonalika
authors.initials: S
authors.lastname: Mahajan
authors.forename: Jajati Keshari
authors.initials: JK
authors.lastname: Mohapatra
authors.forename: Laxmi Kant
authors.initials: LK
authors.lastname: Pandey
authors.forename: Gaurav Kumar
authors.initials: GK
authors.lastname: Sharma
authors.forename: Bramhadev
authors.initials: B
authors.lastname: Pattnaik
mesh_terms: D000086042:3C Viral Proteases; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood*; D000956:Antigens, Viral / Q000235:genetics; D002417:Cattle; D002418:Cattle Diseases / Q000175:diagnosis*; D003546:Cysteine Endopeptidases / Q000235:genetics; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005536:Foot-and-Mouth Disease / Q000175:diagnosis*; D029544:Foot-and-Mouth Disease Virus / Q000276:immunology*; D007159:Immunologic Tests / Q000379:methods*; D007194:India; D011994:Recombinant Proteins / Q000235:genetics; D012680:Sensitivity and Specificity; D014730:Veterinary Medicine / Q000379:methods; D014764:Viral Proteins / Q000235:genetics
chemical_list: D000914:Antibodies, Viral; D000956:Antigens, Viral; D011994:Recombinant Proteins; D014764:Viral Proteins; D003546:Cysteine Endopeptidases; D000086042:3C Viral Proteases
keywords: 2C; DIVA; Foot-and-mouth disease; NSP