Production of polyclonal antibody against the recombinant PirBvp protein of Vibrio parahaemolyticus

Fabrication of lateral flow immunoassay strip for rapid detection of acute hepatopancreatic necrosis disease

Acute hepatopancreatic necrosis disease (AHPND) is a contagious disease for the shrimp cultivation, thus early detection of disease is an unmet need. This present study documented for the first time a simple lateral flow immunoassay (LFIA) strip using polyclonal antibodies was created for the rapid detection both of PirAvp and PirBvp protein simultaneously. LFIA method based on the principle of sandwich format. The label is the colloidal gold. The polyclonal antibody was conjugated with the colloidal gold acting as biorecognition element and coated onto the conjugate pad. The rabbit anti-Pirvp, anti-PirBvp antibodies, and goat anti-rabbit IgG antibody were separately sprayed onto a nitrocellulose membrane to form two test lines and one control line, respectively. The appearance of red bands at the control line and the test line indicated a positive result. A single coloured band at control area indicated a negative result. The limit of detection of LFIA was found to be 125 ng, which could be visually detected by naked eye within 15 min. There was no cross-reactivity observed with VPnon-AHPND. Furthermore, the sensitivity and specificity of LFIA were 94.0% and 98.0%, respectively. The developed test strip could be a game changer for early and in situ diagnosis of AHPND.