Work

Identification of a novel linear B-cell epitope recognized by a monoclonal antibody against the capsid protein of goose astrovirus genotypes 2

Year: 2025

Type: article

Abstract: Goose astrovirus genotype 2 (GoAstV-2) is a novel and highly infectious pathogen characterized by symptoms of gout, swelling, and hemorrhage of the kidneys in 5–15-day-old goslings. The virus has caused severe economic losses for the goose husbandry industry. The capsid protein of GoAstV-2 is involved in viral packaging and immunogenicity, and it has served as a target antigen for diagnostic methods. In this study, the N-terminus of the GoAstV-2 Cap protein (rCap) was successfully expressed and used to immunize BALB/c mice. A new monoclonal antibody (mAb) named 7B2 against the GoAstV-2 rCap protein was prepared. Immunofluorescence assay and Western blot analysis showed that mAb 7B2 had a strong binding affinity to the GoAstV-2 rCap protein. The results of epitope mapping demonstrated that the minimum linear epitope recognized by mAb 7B2 was located in the amino acids 153 NTAGPESIDT 162 . Sequence homology analysis revealed that this epitope was highly conserved among the GoAstV-2 strains analyzed and that it showed 90% sequence similarity with turkey astrovirus 2 strains and low similarity (less than 50%) with other astroviruses. These findings will be useful for the development of diagnostic kits for GoAstV-2 and will aid further research on the structure and function of the capsid protein.

Source: BMC Veterinary Research

DOI: 10.1186/s12917-025-04687-y