Diagnostic methods for African horsesickness virus using monoclonal antibodies to structural and non-structural proteins.

This research article involves the development of diagnostic methods for African horsesickness virus using monoclonal antibodies that react to the virus’ structural and non-structural proteins. The goal was to create a faster and more sensitive way to detect the disease in horses.

Development of Monoclonal Antibodies

• The primary focus of this study was to create a panel of 32 hybridoma cell lines that secrete monoclonal antibodies (MAbs) that react specifically with African horsesickness virus serotype 4 (AHSV-4).
• These 32 hybridoma cell lines were developed with various antibodies targeting different proteins of the virus. Four were specific to the major core antigen VP7, twenty recognized the outer capsid protein VP2, and eight reacted with the non-structural protein NS1.

Sandwich Immunoassay

• Using the VP7-specific MAbs, a double antibody sandwich immunoassay was developed. The purpose of this assay is to detect the viral antigen in infected Vero cells and in spleen tissue from AHSV-infected horses.
• The sandwich immunoassay has a high sensitivity level, being able to detect as little as 10 ng of viral antigen per 100 microliters. This indicates a high level of precision and reliability in identifying the virus at low concentration levels.

Visualizing Non-Structural Protein

• The monoclonal antibodies specific to the non-structural protein NS1 were used to visualize tubule-like structures in the cytoplasm of infected Vero cells via immunofluorescence.
• The ability to see these structures provides a beneficial tool in the diagnosis process, especially for confirmatory procedures where visual evidence of infection is important.

Mapping the Outer Capsid VP2 Protein

• The study also reports on the antigenic map of the outer capsid VP2 protein with the MAbs. This mapping is crucial to understand the interactions between the virus and the antibodies, yielding key information to understand the mechanism of the disease and, possibly, insight into vaccine development strategies.