Location: Food and Feed Safety Research
Title: Differential induction of nitric oxide, degranulation, and oxidative burst activities in response to microbial agonist stimulation in monocytes and heterophils from young commercial turkeys Authors
Submitted to: Veterinary Immunology and Immunopathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 17, 2008
Publication Date: January 21, 2008
Citation: He, H., Genovese, K.J., Swaggerty, C.L., Nisbet, D.J., Kogut, M.H. 2008. Differential induction of nitric oxide, degranulation, and oxidative burst activities in response to microbial agonist stimulation in monocytes and heterophils from young commercial turkeys. Veterinary Immunology and Immunopathology. 123(3-4):177-185. Interpretive Summary: Heterophils and monocytes are turkey white blood cells. They are important immune cells that can produce chemicals to kill bacteria. These bacteria-killing chemicals help turkeys fight infections and stay healthy. Toll-like receptors are a type of proteins that stay on the surface of the turkey white blood cells and recognize the chemical elements of bacteria. Here, we investigated the functions of the Toll-like receptors by exposure of turkey white blood cells to different chemical elements of bacteria. We have found that the Toll-like receptors of turkey white blood cells can identify many chemical elements of bacteria and allow the turkey white blood cells to produce large amount of bacteria-killing chemicals. These results suggest that some of those chemical elements of bacteria can be used to stimulate the immunity of young turkeys. This information is important to the pharmaceutical and poultry industries in the United States because it may offer a new method to increase the immunity of young turkeys and reduce the use of antibiotics.
Technical Abstract: The Toll-like receptors (TLRs) recognize microbial pathogens and pathogen associated molecular patterns and trigger inflammatory immune responses to control the infection. Here, we examined functional innate immune responses to Salmonella enteritidis (SE, live or formalin-killed) and various TLR agonists including lipoteichoic acid (LTA) and peptidoglycan (PGN) from Staphylococcus aureus and synthetic lipoprotein Pam3CSK4 (PAM), poly I:C (synthetic double stranded RNA analog), lipopolysaccharide (LPS) from S. enteritidis, flagellin (FGN) from S. typhimurium, loxoribine (LOX) and R837 (synthetic anti-viral compounds), and CpG oligodeoxydinucleotide (CpG ODN)by measuring antimicrobial activities including oxidative burst and degranulation in heterophils and nitric oxide production in peripheral blood monocytes. Our results demonstrate differential nitric oxide responses to TLR agonists in turkey monocytes. LTA and CpG ODN were the most potent stimuli for nitric oxide induction followed by PAM, poly I:C, and LPS, whereas FGN, PGN, LOX, R837, and control ODN stimulated little or no nitric oxide production. Live SE stimulated significantly less NO production than formalin-killed SE (FKSE). Although FKSE induced significant degranulation and oxidative burst, most TLR agonists stimulate little oxidative burst and degranulation responses in turkey heterophils.