Development of a Recombinant Antibody-Based Lateral Flow Immunoassay for White Spot Syndrome Virus (WSSV) Detection Using VP24, VP26, And VP35 Proteins

Abstract

White Spot Syndrome Virus (WSSV) remains a major threat to shrimp aquaculture, causing mass mortality and severe economic losses. Rapid and field-deployable diagnostics are crucial to prevent viral outbreaks. In this study, we cloned, expressed, and purified three recombinant structural proteins of WSSV—VP24, VP26, and VP35—for immunodiagnostic applications. All proteins were expressed in E. coli and purified to high homogeneity, yielding 3.1–4.3 mg/L. Polyclonal antibodies raised against these proteins elicited strong immune responses, with ELISA titers reaching 1:6,400. VP35 showed the highest antibody reactivity, followed by VP26 and VP24. Lateral flow immunoassay (LFA) strips developed using these antibodies demonstrated sensitivity values ranging from 82–90% and specificity between 91–95%, with detection limits as low as 10³ viral copies/mL. These findings suggest that VP26 and VP35 are promising diagnostic antigens and establish the LFA platform as a cost-effective, portable, and rapid diagnostic tool for WSSV detection in shrimp aquaculture.