Elevated serum haptoglobin in pigs infected with porcine reproductive and respiratory syndrome virus

We examined the two acute phase proteins, alpha (alpha)-1 acid glycoprotein (AGP) and haptoglobin (HP), in serum of pigs following experimental porcin e reproductive and respiratory syndrome (PRRS) virus infection. Increased l evels of serum HP, but not AGP, were observed from 7 to 21 days post-inocul ation in the infected pigs. Furthermore, serum IL-6 increased in the infect ed pigs, but TNF-alpha did not. The increase of serum IL-6 in pigs followin g PRRS virus infection may induce production of HP. Also, in the field inve stigation, serum HP in pigs was dramatically increased after exposure to th e PRRS virus. (C) 1999 Elsevier Science B.V. All rights reserved.