The serologic response of horses to equine arteritis virus as determined by competitive enzyme-linked immunosorbent assays (c-ELISAs) to structural and non-structural viral proteins.

This study sought to further investigate the immune response of horses to equine arteritis virus (EAV) by developing direct and competitive enzyme-linked immunosorbent assays to identify structural and non-structural viral proteins. Though they were not as sensitive as existing methods, these new processes confirmed that the M protein is a major target of the horse’s immune response to EAV.

Development of New Assays

• The research focused on improving the understanding of the horse’s immune system’s response to the equine arteritis virus (EAV).
• An effort was made to develop direct and competitive enzyme-linked immunosorbent assays (c-ELISAs), which are laboratory tests widely used to detect and measure specific proteins or antibodies.
• Both monoclonal and polyclonal antisera were used in these tests to pinpoint structural (G(L), N, and M) and non-structural (nsp1) viral proteins.
• A unique monoclonal antibody targeting the non-structural protein nsp1 was also produced to facilitate the construction of a c-ELISA for this protein.

Findings and Conclusions

• The data obtained using the different c-ELISAs showed that the M protein is a primary target of the horse’s antibody response to EAV.
• This reaffirms the importance of the M protein within the virus and could be significant for furthering our understanding of the horse’s immune response mechanism to EAV.
• However, despite these new developments, none of the newly designed c-ELISAs were as sensitive in detecting EAV-specific antibodies in horse serum as the pre-existing serum neutralization test.
• This suggests that while the new c-ELISAs contribute to our understanding of the horse’s immune response to EAV, the development of even more sensitive tests in the future might still be necessary.