Integrin engagement induces monocyte procoagulant activity and tumor necrosis factor production via induction of tyrosine phosphorylation
Integrin engagement induces monocyte procoagulant activity and tumor necrosis factor production via induction of tyrosine phosphorylation
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DOI：
10.1006/jsre.1996.0330
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发表时间：
1996-08-01
影响因子：
2.2
通讯作者：
Rotstein, OD
中科院分区：
文献类型：
--
作者：
Dackiw, APB;Nathens, AB;Rotstein, OD
单核细胞与内皮细胞表面和下层细胞外基质蛋白的特异性相互作用是通过表面粘附分子介导的，特别是整合素家族的那些。最近的研究表明，这些相互作用可能在调节基因表达和细胞功能方面很重要。我们测试的假设，参与单核细胞表面整合素，模拟整合素/配体的相互作用，可能会调节单核细胞促凝血活性（PCA）和肿瘤坏死因子（TNF）的生产。将来自合并的大鼠血液的单核细胞与小鼠抗大鼠VLA-4（β 1整联蛋白）抗体（20 μ g/ml）或小鼠抗大鼠Mac-1（β 2整联蛋白）抗体（20 μ g/ml）孵育，洗涤，然后将细胞表面整联蛋白与山羊抗小鼠IgG抗体（20 μ g/ml）交联。在37 ° C下孵育4小时后，吸出上清液并通过ELISA测试TNF，并将细胞沉淀物冷冻-解冻以在一阶段凝血测定中测量PCA。单核细胞上β 1整合素VLA-4或β 2整合素Mac-1的交联显著增加细胞促凝血活性和TNF产生（PCA mU/10（6）细胞：对照，30 +/- 3;抗VLA-4，131 +/- 33;抗Mac-1，152 +/- 29; TNF pg/ml：对照，60 +/- 4;抗VLA-4，548 +/- 38;抗Mac-1，701 +/- 134）。由于酪氨酸磷酸化参与巨噬细胞信号转导，我们研究了整合素连接是否可能刺激这一途径。通过Western印迹分析，整合素VLA-4的交联显示诱导酪氨酸磷酸化蛋白的积累，这种作用被酪氨酸激酶抑制剂染料木黄酮抑制。在平行研究中，染料木黄酮抑制细胞PCA。综合考虑，这些研究表明，整合素参与后的单核细胞活化是通过刺激酪氨酸激酶活性诱导的。因此，除了介导细胞粘附外，表面整合素可能在炎症部位调节细胞功能中起作用。(C)出版社：Academic Press，Inc.
The specific interactions of monocytes with the endothelial cell surface and underlying extracellular matrix proteins are mediated via surface adhesion molecules, particularly those of the integrin family. Recent studies have suggested that these interactions may be important in modulating gene expression and thus cell function. We tested the hypothesis that engagement of surface integrins on monocytes, simulating integrin/ligand interactions, might modulate monocyte procoagulant activity (PCA) and tumor necrosis factor (TNF) production. Mononuclear cells from pooled rat blood were incubated with a mouse anti-rat VLA-4 (beta 1 integrin) antibody (20 mu g/ml), or a mouse anti-rat Mac-1 (beta 2 integrin) antibody (20 mu g/ml), washed, and then cell surface integrins were crosslinked with a goat anti-mouse IgG antibody (20 mu g/ml). After incubation at 37 degrees C for 4 hr, supernatants were aspirated and tested for TNF by ELISA and cell pellets were freeze-thawed for measurement of PCA in a one-stage clotting assay. Crosslinking of the beta 1 integrin VLA-4 or the beta 2 integrin Mac-1 on monocytes significantly increased cellular procoagulant activity and TNF production (PCA mU/10(6) cells: control, 30 +/- 3; anti-VLA-4, 131 +/- 33; anti-Mac-1, 152 +/- 29; TNF pg/ml: control, 60 +/- 4; anti-VLA-4, 548 +/- 38; anti-Mac-1, 701 +/- 134). Since tyrosine phosphorylation participates in macrophage signaling, we studied whether integrin ligation might stimulate this pathway. By Western blot analysis, crosslinking of the integrin VLA-4 was shown to induce the accumulation of tyrosine phosphorylated proteins, an effect which was inhibited by the tyrosine kinase inhibitor genistein. In parallel studies, genistein inhibited cellular PCA. Considered together, these studies suggest that monocyte activation following integrin engagement is induced by stimulation of tyrosine kinase activity. Thus, in addition to mediating cell adhesion, surface integrins may play a role in modulating cell function at sites of inflammation. (C) 1996 Academic Press, Inc.