Priming effects of lipopolysaccharide and inflammatory cytokines on canine granulocytes.
Granulocytes play a pivotal role in natural immunity. Under inflammatory conditions, granulocytes are universally primed by several agents, such as endotoxins and inflammatory cytokines. Primed granulocytes exert potent adhesiveness, chemotaxis, phagocytosis and reactive oxygen species (ROS) production, effectively eliminating invading agents. Reactivity against priming agents is known to vary with species; however, there have been few reports on the effects of priming agents on canine granulocytes. In the present study, we assayed the priming effects of lipopolysaccharide (LPS), recombinant canine tumor necrosis factor-alpha (rcTNF-alpha) and recombinant canine granulocyte macrophage colony-stimulating factor (rcGM-CSF) on canine granulocyte function in vitro. Isolated recombinant canine were primed with various concentrations of LPS, rcTNF-alpha and rcGM-CSF, and CD11b expression was assayed. Furthermore, actin polymerization, phagocytosis and ROS production were then assayed at primer concentrations where enhancement of CD11b expression was observed. LPS did not enhance canine granulocyte function. Phagocytosis and actin polymerization were not enhanced by priming agents; however, rcTNF-alpha and rcGM-CSF enhanced CD11b expression and ROS production in canine granulocytes. These results suggest that priming effects are mainly reflected in CD11b expression and ROS production, with rcGM-CSF and rcTNF-alpha having a priming effect similar to that observed in humans.
Maeda
Kenichi
K
School of Veterinary Medicine, Kitasato University, Aomori, Japan.
Sakonju
Iwao
I
Kanda
Aya
A
Suzuki
Tatsuya
T
Kakuta
Tomoko
T
Shimamura
Shunsuke
S
Okano
Shozo
S
Takase
Katsuaki
K
D000199:Actins / Q000378:metabolism; D000818:Animals; D039481:CD11b Antigen / Q000235:genetics / Q000378:metabolism; D002478:Cells, Cultured; D016207:Cytokines / Q000633:toxicity*; D004285:Dogs; D005786:Gene Expression Regulation; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000633:toxicity*; D006098:Granulocytes / Q000187:drug effects*; D008070:Lipopolysaccharides / Q000633:toxicity*; D010587:Phagocytosis / Q000187:drug effects; D016897:Respiratory Burst; D014409:Tumor Necrosis Factor-alpha / Q000633:toxicity*
D000199:Actins; D039481:CD11b Antigen; D016207:Cytokines; D008070:Lipopolysaccharides; D014409:Tumor Necrosis Factor-alpha; D016178:Granulocyte-Macrophage Colony-Stimulating Factor