University of Minnesota - “Direct Physical Characterization of the PRRSV Virion”

Project Summary
Precise and specific knowledge of the physical characteristics of a viral particle provides the basic information about surface antigen candidates for neutralizing antibodies, receptor-binding structural candidates for inhibitors, and essential proteins that initiate the infection process. Surprisingly little is known about the North American PRRSV virion. This information will help to identify likely and unlikely targets for immune protection, to better understand the infectious process, and to guide the development of strategies for reducing or preventing disease in infected pigs.

Project Objective
To determine the complete protein composition of the North American PRRSV virion by a method that is not limited to the availability of antibodies or to preconceived notions about which proteins are expressed from the viral genome.

Relevance to NPB PRRS Initiative Research Objectives
PRRSV clearly does not behave like many other viral diseases of pigs, such as influenza virus, TGE virus, pseudorabies virus, PRCV, and FMDV. Both the 4-5 week course of acute, viremic infection and the months-long persistence in lymphoid tissues are exceptional. Therefore, a better approach to understanding and solving the problem of PRRS in pigs is to begin with concrete knowledge about the virus and the pig’s response. This research proposes to determine the viral proteins that comprise the virion and identify the external epitopes, or regions, that have the potential to interact with host cell membranes and neutralizing antibodies.