REGULATION OF BOVINE ACUTE-PHASE RESPONSES BY RECOMBINANT INTERLEUKIN-1-BETA

The acute phase response is a collection of physiologic changes initia ted early in the inflammatory process. This response is comprised of b oth localized changes at the site of infection or injury and the initi ation of systemic responses, such as the increase in production of acu te phase proteins, Cytokines such as interleukin (IL)-1, IL-6, and tum or necrosis factor (TNF) play key roles in the regulation of acute pha se response in the species studied to date, To better characterize the acute phase response of cattle, recombinant bovine (rBo) IL-1 beta wa s administered to cattle, A single administration of rBoIL-1 beta was able to induce a dose dependent increase in body temperature, circulat ing leukocytes, and serum haptoglobin and fibrinogen concentrations, a s well as a decrease in plasma zinc concentration, Five daily administ rations of rBoIL-1 beta resulted in heightened and prolonged elevation s of haptoglobin and fibrinogen, In addition, alpha(1)-acid glycoprote in levels were increased, a response not seen after a single administr ation of rBoIL-1 beta. These results indicate that IL-1 is an importan t regulator of the acute phase response in cattle,