Work

B-cell epitope mapping of VP5 protein of bluetongue virus serotype 1 using monoclonal antibodies

Year: 2025

Type: article

Abstract: • Truncation of the 79 N-terminal amino acids significantly facilitated VP5 expression in Escherichia coli, enabling the production of recombinant VP5Δ1-79aa. • Five monoclonal antibodies (mAbs) specific to BTV1 VP5 were generated using hybridoma technology. • Comprehensive epitope mapping with the generated mAbs identified four novel linear B-cell epitopes within the BTV-1 VP5 protein. • These findings provide critical insights for the development of diagnostic tools and vaccines against BTV-1. Bluetongue (BT) is a severe infectious disease affecting ruminants, caused by the bluetongue virus (BTV), an Orbivirus transmitted by Culicoides midges. VP5 is a major component of the outer capsid of BTV, and a key constituent of BTV subunit and virus-like particle vaccines. However, to date, the B-cell epitopes on VP5 recognized by humoral immune responses remain unidentified. In this study, recombinant VP5Δ1-79aa was expressed in Escherichia coli ( E. coli ) and purified for mouse immunization. Five monoclonal antibodies (mAbs) were identified through hybridoma fusion, clonal selection, and immunological assays. B-cell epitopes were recognized by mAbs 4G9, 6C9, 3A1, 3C8 and 6B1, these epitopes were mapped using a series of truncated overlapping peptides expressed as glutathione S-transferase fusion proteins. 4G9 recognized the 144 DEKQFDILNK 153 sequence, 6C9 recognized 154 AVTSYNKILT 163 , 3A1 and 3C8 recognized 207 VERDGMQEEA 216 , and 6B1 recognized 312 ENHKELMHIK 321 . These specific mAbs and their corresponding B-cell epitopes provide valuable insights into the structure and function of VP5, contributing to the advancement of serological diagnostic methods and development of epitope-based vaccines for BTV.

Source: Virus Research

DOI: 10.1016/j.virusres.2025.199663