Submitted to: Veterinary Immunology and Immunopathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: February 20, 2001
Publication Date: N/A
Interpretive Summary: Disease and sickness produce many changes in blood. One such change includes an increase or decrease in certain proteins in serum. Using croton oil, we induced chemical irritation in chickens and found an increase and decrease in several serum proteins. To find why these changes are important, we conducted experiments and showed that serum from birds with chemically-induced irritation increase antibacterial activities of macrophages, a type of white blood cells responsible for defense against bacteria.
Technical Abstract: Inflammation-induced changes in serum protein profiles and the effects of such serum on a chicken macrophage cell line HD11 were studied to find whether the changes in serum affect cellular immunity. Four-week-old male broiler chickens were injected subcutaneously with either olive oil or 50% croton oil mixed in olive oil to induce inflammation. The birds were bled at 48 h after injection, and serum protein profiles were compared using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). At 48 h post-injection the serum from croton oil-injected birds showed distinct changes in protein profiles characterized by a selective increase or decrease in levels of several serum proteins. The protein bands which showed increases had molecular weights (Mr) corresponding to 65 kD, 42 kD, and two or more proteins with Mr #200 kD. The levels of serum albumin (49 kD), and a 56 kD protein were reduced in croton oil-injected birds. The modulating effects of such serum on HD11 cells were studied using bacteria lipopolysaccharide (LPS) or phorbol myristate acetate (PMA) induced functional activation of these cells. The LPS-induced interleukin-6 (IL-6) production by HD11 cells was not affected by the presence of either olive oil-treated control or croton oil-treated inflammatory serum but nitrite production was enhanced by the inflammatory serum. Similarly, inflammatory serum also enhanced PMA-induced respiratory burst measured using dichlorofluorescein diacetate (DCF-DA) oxidation mediated by reactive oxygen intermediates. These results suggest that inflammatory serum can modulate macrophage function by influencing the production of reactive oxygen and nitrogen species which could affect their phagocytic and bactericidal activities.