The Development and Validation of a Novel Nanobody-Based Competitive ELISA for the Detection of Foot and Mouth Disease 3ABC Antibodies in Cattle.

Sigal Gelkop,Polina Brangel,Julius Julian Lutwama,Nick Strom,Frank Norbet Mwiine,Ema Romão,Shlomit Fedida-Metula,Irene Ataliba,Victoria Yavelsky,Ariel Sobarzo,Rachel A Mckendry,Sylvester Ochwo,Leslie Lobel,Serge Muyldermans,Cécile Vincke,Elizabeth Rieder,Lauro Velazquez-Salinas

doi:10.3389/fvets.2018.00250

Abstract

Effective management of foot and mouth disease (FMD) requires diagnostic tests to distinguish between infected and vaccinated animals (DIVA). To address this need, several enzyme-linked immunosorbent assay (ELISA) platforms have been developed, however, these tests vary in their sensitivity and specificity and are very expensive for developing countries. Camelid-derived single-domain antibodies fragments so-called Nanobodies, have demonstrated great efficacy for the development of serological diagnostics. This study describes the development of a novel Nanobody-based FMD 3ABC competitive ELISA, for the serological detection of antibodies against FMD Non-Structural Proteins (NSP) in Uganda cattle herds. This in-house ELISA was validated using more than 600 sera from different Uganda districts, and virus serotype specificities. The evaluation of the performance of the assay demonstrated high diagnostic sensitivity and specificity of 94 % (95 % CI: 88.9–97.2), and 97.67 % (95 % CI: 94.15–99.36) respectively, as well as the capability to detect NSP-specific antibodies against multiple FMD serotype infections. In comparison with the commercial PrioCHECK FMDV NSP-FMD test, there was a strong concordance and high correlation and agreement in the performance of the two tests. This new developed Nanobody based FMD 3ABC competitive ELISA could clearly benefit routine disease diagnosis, the establishment of disease-free zones, and the improvement of FMD management and control in endemically complex environments, such as those found in Africa.

Highlights

Foot-and-mouth disease (FMD), is a highly contagious disease caused by foot and mouth disease (FMD) virus (FMDV), which is responsible for significant economic losses worldwide [1,2,3]
This study describes the development and validation of a new Nb-based FMD 3ABC competitive enzyme-linked immunosorbent assay (ELISA) for the detection of anti-FMDV NonStructural Proteins (NSP) antibodies in cattle serum in Uganda
These specific peptides were selected based on their amino acid sequence conservation among the seven serotypes of FMDV and have the potential to interact with antibodies against NSP of multiple viral serotype strains

Summary

Introduction

Foot-and-mouth disease (FMD), is a highly contagious disease caused by FMD virus (FMDV), which is responsible for significant economic losses worldwide [1,2,3]. Global FMD control strategy includes reliable and effective surveillance and is supported by competent laboratory diagnostic services [9, 15] Such diagnosis is typically carried out by the combination of virus isolation, serological tests, and nucleic acid recognition methods [9, 16]. Serological tests are an essential component in the diagnosis algorithm of FMD because it is required for animal’s import/export certification, as well as to determine the “free-from-infection” animal state and demonstrate vaccine efficacy [17] In this regard, the detection of antibodies to viral non-structural proteins, NSPs, is considered as one of the most important indicators of infection, irrespective of vaccination status [18], and is routinely performed in FMD free and endemic countries where vaccination is used [19]

Methods

Results

Conclusion