LPS对猪中性粒细胞Mac-1表达的影响及相关信号机制

On the effects and mechanisms of LPS on Mac-1 expression in porcine neutrophils

【目的】研究致炎因子LPS对猪中性粒细胞表达巨噬细胞表面分子抗原(Mac)-1的诱导作用及有关的信号机制,为LPS致炎机制及抗炎药物机理研究提供依据。【方法】采用密度梯度离心法分离猪中性粒细胞,以流式细胞术检测Mac-1表达,以实时荧光定量PCR检测p38丝裂原活化蛋白激酶(p38 MAPK)、磷脂酰肌醇-3-激酶(PI3K)、Janus激酶(JAK)、p65核转录因子(p65 NF-κB)mRNA相对表达量。【结果】1、10、100、1000 ng/mL的LPS对猪中性粒细胞Mac-1表达表现出增加趋势,其中100、1000 ng/mL的LPS明显促进Mac-1表达,差异极显著(P<0.01)。1、10、100、1000 ng/mL的LPS可呈剂量依赖性促进猪中性粒细胞JAK mRNA表达(P<0.01);100 ng/mL LPS可显著促进p38 MAPK mRNA表达(P<0.05);10 ng/mL LPS可分别显著促进PI3K、p65 NF-κB mRNA表达(P<0.05)。【结论】LPS呈剂量依赖性诱导猪中性粒细胞Mac-1表达,其信号机制与上调JAK和p38 MAPKmRNA表达有关。

[Objective]To Clarify the signaling pathway and related molecular mechanism of LPS-induced Mac-1 expression in porcine neutrophils,for providing insight into the mechanism of LPS-induced inflammatory and anti-inflammatory drugs.[Methods]Neutrophils were isolated from the blood through a density gradient centrifugation.Mac-1 expression was detected by flow cytometry.The relative mRNA expressions level of p38 MAPK,PI3K,JAK,and p65 NF-κB were detected by real-time polymerase chain reaction(PCR).[Results]Up-regulation of Mac-1 expression by LPS-stimulated porcine neutrophils was observed in a dose-dependent fashion(P<0.01).Among them,100 and 1000 ng/mL LPS significantly promoted the expression of Mac-1(P<0.01).LPS at 1,10,100,and 1000 ng/mL could promote JAK mRNA expression in porcine neutrophils in a dose-dependent manner(P<0.01).100 ng/mL LPS could significantly promote the expression of p38 MAPK mRNA(P<0.05).10 ng/mL LPS could significantly promote mRNA expression of PI3K and p65 NF-κB,respectively(P<0.05).[Conclusion]LPS upregulates the expression of Mac-1 on porcine neutrophils in a dose-dependent fashion,and its mechanism is at least related to the mRNA up-regulation of p38 MAPK and JAK.