Construction of a FMDV-specific recombinant antibody phage-display bovine library for epitope identification and diagnostic reagents

MANGENA, MARUPING ; FEHRSEN, JEANNI ; MIRAGLIA, MARIA CRUZ ; OPPERMAN, PAMELA ; MANSILLA, FLORENCIA C.; PEREZ-FILGUEIRA, DANIEL MARIANO; CAPOZZO, ALEJANDRA V.; CHITRAY, MELANIE

Kruger Park

Simposio; IVIS 2023 - 13th International veterinary immunology symposium; 2023

Foot-and-mouth disease (FMD) is caused by the foot-and-mouth disease virus (FMDV). It is the most wide-spread transboundary disease due to its highly infectious nature and is endemic in many African countries including, South Africa. There are seven serotypes of FMDV i.e., SAT1, SAT2, SAT3, A, O, C, and Asia1. The disease affects cloven-hoofed animals such as cattle, sheep, pigs and goats. Furthermore, it causes significant economic losses due to high morbidity in infected animals and stringent trade restrictions imposed on animal products from affected countries. An important control measure is vaccination, however, the FMDV high mutation rate results in antigenic variation rendering vaccines less effective. Knowledge of FMDV epitopes is advantageous and can be included in FMDV recombinant vaccine development resulting in vaccines that induce a broad immunological response and thus offer improved protection. In this regard, a bovine immune recombinant phage antibody library was constructed, using tissue samples taken from the (right) prescapular lymph nodes of six Jersey steers vaccinated with a commercial tetravalent FMD vaccine used in Argentina. Following RNA extraction, variable heavy (VH) and light chain (VL) regions of the immunoglobulin G antibody (IgG) genes were amplified by RT-PCR, joined by a flexible linker and cloned into a phagemid vector. The construct was transformed into electro-competent E.coli TG1 cells and an immune library constructed consisting of 1.8 X 107 different clones. Biopanning will be used to identify FMDV-specific single-chain variable fragments (scFvs). These scFvs will be utilised to identify FMDV epitopes and investigate its potential as reagents in a diagnostic ELISA. This is the first report of a FMDV-specific bovine phage library construction.