Maeda Kenichi, Sakonju Iwao, Kanda Aya, Suzuki Tatsuya, Kakuta Tomoko, Shimamura Shunsuke, Okano Shozo, Takase Katsuaki
School of Veterinary Medicine, Kitasato University, Aomori, Japan.
J Vet Med Sci. 2010 Jan;72(1):55-60. doi: 10.1292/jvms.08-0494. Epub 2009 Nov 13.
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.
粒细胞在天然免疫中起关键作用。在炎症条件下，粒细胞普遍会被多种因子激活，如内毒素和炎性细胞因子。被激活的粒细胞具有强大的黏附性、趋化性、吞噬作用和活性氧（ROS）生成能力，能有效清除入侵病原体。已知不同物种对激活因子的反应性存在差异；然而，关于激活因子对犬粒细胞影响的报道却很少。在本研究中，我们检测了脂多糖（LPS）、重组犬肿瘤坏死因子-α（rcTNF-α）和重组犬粒细胞巨噬细胞集落刺激因子（rcGM-CSF）对犬粒细胞体外功能的激活作用。将分离出的重组犬用不同浓度的LPS、rcTNF-α和rcGM-CSF进行激活，并检测CD11b的表达。此外，在观察到CD11b表达增强的激活剂浓度下，检测肌动蛋白聚合、吞噬作用和ROS生成。LPS未增强犬粒细胞功能。激活剂未增强吞噬作用和肌动蛋白聚合；然而，rcTNF-α和rcGM-CSF增强了犬粒细胞中CD11b的表达和ROS生成。这些结果表明，激活作用主要体现在CD11b表达和ROS生成上，rcGM-CSF和rcTNF-α具有与人类相似的激活作用。
