PRRS is the most costly disease U.S. swine producers confront and little progress has been made in recent years to mprove the situation. In studying swine antibody responses, we discovered the presence of serum auto-anti-idiotypic antibodies in pigs experimentally infected with PRRSV. Clearance of virus from these animals was associated with the earlier appearance of auto-anti-idiotypic antibodies post infection. We have recently produced a monoclonal anti-idiotypic antibody (designated Mab2-3H) that is functionally like GP5 antigen of PRRS virus by inducing anti-GP5 antibodies in mice and pigs. More importantly, these anti-GP5 antibodies neutralized PRRS virus infection of Marc cells. These results will lead immediately to future work by examining the effectiveness of Mab2-3H in protecting pigs from PRRS virus infection, understanding the mechanism(s) of Mab2-3H-induced protective immunity against PRRS virus infection at molecular and cellular levels and developing a potential marker vaccine and differential diagnostic test to prevent and control PRRS.

For further information please contact Dr. En-Min Zhou at the Department of Veterinary Diagnostic and Production Animal Medicine, 2656 Vet Med Building, Iowa State University, Ames, Iowa 50011. Tel. 515-294-4699, Fax. 515-294-3564, Emai: [email protected]