Eotaxin induces degranulation and chemotaxis of eosinophils through the activation of ERK2 and p38 mitogen-activated protein kinases
Eotaxin induces degranulation and chemotaxis of eosinophils through the activation of ERK2 and p38 mitogen-activated protein kinases
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DOI：
10.1182/blood.v95.6.1911
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发表时间：
2000-03-15
期刊：
影响因子：
20.3
通讯作者：
Alam, R
中科院分区：
文献类型：
--
作者：
Kampen, GT;Stafford, S;Alam, R
嗜酸性粒细胞趋化因子和其他CC趋化因子通过CC趋化因子受体-3(CCR3)作用于哮喘和过敏性炎症，在哮喘和过敏性炎症性疾病的发展中起着不可或缺的作用，然而，激动剂与CCR3结合后的细胞内事件以及这些事件与细胞功能反应的关系却知之甚少。本研究的目的是研究CCR3介导的丝裂原激活蛋白(MAP)激酶胞外信号调节蛋白-2(ERK2)、p38和c-jun氨基末端激酶(JNK)在嗜酸性粒细胞中的激活，并评估嗜酸性粒细胞阳离子蛋白(ECP)释放和趋化中对MAP的需求。在嗜酸性粒细胞(纯度大于97%)的刺激下，用免疫印迹和免疫复合激活法研究了MAPK的激活。放射免疫法测定ECP释放量。用Boyden微室检测细胞的趋化性。嗜酸性粒细胞趋化因子(10(-11)~10(-7)mol/L)可诱导ERK2和p38的浓度依赖性磷酸化，30s后即可检测到磷酸化，1min左右达到高峰，2~5min后恢复到基线水平。未检测到高于基线水平的JNK的磷酸化。ERK2和p38的活性与磷酸化平行，ERK2激活酶MEK(MAP ERK)的抑制剂PD980 59以浓度依赖的方式阻断ERK2的磷酸化。用PD98 059研究ERK2和p38的功能相关性，p38抑制剂SB202 190、PD98 059和SB202 190均可抑制嗜酸性粒细胞趋化因子诱导的ECP释放和趋化。我们的结论是，嗜酸性粒细胞中的ERK2和p38的快速激活依赖于浓度，并且这些MAPK的激活是嗜酸性粒细胞脱颗粒和定向运动所必需的。(C)2000年，由美国血液病学会提供。
Eotaxin and other CC chemokines acting via CC chemokine receptor-3 (CCR3) are believed to play an integral role in the development of eosinophilic inflammation in asthma and allergic inflammatory diseases, However, little is known about the intracellular events following agonist binding to CCR3 and the relationship of these events to the functional response of the cell. The objectives of this study were to investigate CCR3-mediated activation of the mitogen-activated protein (MAP) kinases extracellular signal-regulated kinase-2 (ERK2), p38, and c-jun N-terminal kinase (JNK) in eosinophils and to assess the requirement for MAP kinases in eotaxin-induced eosinophil cationic protein (ECP) release and chemotaxis. MAP kinase activation was studied in eotaxin-stimulated eosinophils (more than 97% purity) by Western blotting and immune-complex kinase assays. ECP release was measured by radioimmunoassay. Chemotaxis was assessed using Boyden microchambers. Eotaxin (10(-11) to 10(-7) mol/L) induced concentration-dependent phosphorylation of ERK2 and p38, Phosphorylation was detectable after 30 seconds, peaked at about 1 minute, and returned to baseline after 2 to 5 minutes. Phosphorylation of JNK above baseline could not be detected. The kinase activity of ERK2 and p38 paralleled phosphorylation, PD980 59, an inhibitor of the ERK2- activating enzyme MEK (MAP ERK kinase), blocked phosphorylation of ERK2 in a concentration-dependent manner. The functional relevance of ERK2 and p38 was studied using PD98 059 and the p38 inhibitor SB202 190, PD98 059 and SB202 190 both caused inhibition of eotaxin-induced ECP release and chemotaxis. We conclude that eotaxin induces a rapid concentration-dependent activation of ERK2 and p38 in eosinophils and that the activation of these MAP kinases is required for eotaxin-stimulated degranulation and directed locomotion. (C) 2000 by The American Society of Hematology.