PLATELET REGULATION OF MONOKINE SYNTHESIS

单因子合成的血小板调节

• 批准号: 2030175
• 负责人: Andrew S Weyrich
• 金额: $ 9.7万
• 依托单位: UNIVERSITY OF UTAH
• 依托单位国家: 美国
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-05-01 至 2001-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2030175
• 关键词: T lymphocyte; atherosclerotic plaque; biological signal transduction; chemokine; clinical research; enzyme activity; human subject; immunoregulation; inflammation; interleukin 8; monokines; nuclear factor kappa beta; platelet activation; protein biosynthesis; protein kinase; selectins; tumor necrosis factor alpha

DESCRIPTION: The long term goal of this project is to understand how platelets regulate monocyte function. This issue is particularly important since platelets interact with monocytes in a variety of atherosclerotic disorders. The applicant recently demonstrated that activated platelets, but not unstimulated platelets, induce immediate- early (IE) gene expression in monocytes. Among the IE genes expressed, interleukin-8 (IL-8) and monocyte chemotactic protein-1 (MCP-1) were synthesized and secreted by monocytes exposed to activated platelets. Other IE genes, including tumor necrosis factor-2 (TNF-2), were not generated. Initial results indicate that P-selectin and RANTES (Regulated upon Activation Normal T Cell Expressed presumed Secreted), two platelet-derived molecules, are required for both IL-8 and MCP-1 synthesis in monocytes through P-selectin and RANTES. Signaling in monocytes through P-selectin and RANTES will be compared to signaling induced by LPS, a potent monocyte agonist. In the first Specific Aim, the applicant will further characterize how P-selectin and RANTES regulate monokine synthesis. These studies will initially be defined in a reduced system where different forms of purified P-selectin and RANTES are presented to monocytes; and cellular MRNA, cellular retained protein, and secreted protein for IL-8, MCP-1, and TNF-2 will be measured. A more complex system involving platelet-monocyte interactions to determine if P-selectin and RANTES are required for monokine production will be examined. Specific Aim 3 will determine if P-selectin and RANTES regulate NF-kappaB activity in monocytes. NF- kappaB is a transcription factor that is required for maximal IL-8, MCP-1, and TNF-2 synthesis, and initial results developed by the applicant indicate that NF-kappaB, and its inhibitory factor IkappaB-2, are activated by P-selectin and RANTES. The third Specific Aim will determine if P-selectin and RANTES regulate p70 S6 kinase activity in monocytes. p70 S6 kinase is known to translationally regulate many proteins and other evidence also indicates that p70 S6 kinase can regulate NF-kappaB family members. Initial results suggest that p70 S6 kinase activity is increased in monocytes following exposure to P- selectin and RANTES or activated platelets. Moreover, inhibition of p70 S6 kinase activity by rapamycin attenuates MCP-1 secretion by monocytes exposed to activated platelets. In the final Specific Aim, correlative studies to determine if P-selectin and RANTES are localized in ruptured carotid arterial plaques will be coordinated. Together, these results will begin defining how activated platelets, through P-selectin and RANTES, induce monokine synthesis.

描述：该项目的长期目标是了解如何 血小板调节单核细胞功能。 这个问题特别 很重要，因为血小板在多种情况下与单核细胞相互作用 动脉粥样硬化性疾病。申请人最近证明 活化的血小板，但不是未刺激的血小板，会立即诱导 单核细胞中的早期（IE）基因表达。 在表达的 IE 基因中， 白细胞介素 8 (IL-8) 和单核细胞趋化蛋白 1 (MCP-1) 由暴露于活化血小板的单核细胞合成和分泌。 其他 IE 基因，包括肿瘤坏死因子-2 (TNF-2)，没有被检测到。 生成的。 初步结果表明 P-选择素和 RANTES （根据正常 T 细胞表达和分泌的激活进行调节）， IL-8 和 MCP-1 都需要两种血小板衍生分子 通过 P-选择素和 RANTES 在单核细胞中合成。信号输入 通过 P-选择素和 RANTES 的单核细胞将与信号传导进行比较 由 LPS（一种有效的单核细胞激动剂）诱导。在第一个具体目标中， 申请人将进一步描述 P-选择素和 RANTES 如何 调节单核因子的合成。这些研究最初将被定义 在一个简化的系统中，其中不同形式的纯化 P-选择素和 RANTES 被呈递给单核细胞； 和细胞 mRNA，细胞保留 蛋白以及 IL-8、MCP-1 和 TNF-2 的分泌蛋白将 测量。 涉及血小板单核细胞的更复杂的系统 相互作用以确定 P-选择素和 RANTES 是否是必需的 将检查单核因子的生产。 具体目标 3 将确定 如果 P-选择素和 RANTES 调节单核细胞中的 NF-κB 活性。 NF- kappaB 是最大 IL-8 所需的转录因子， MCP-1 和 TNF-2 的合成以及由 申请人指出NF-kappaB及其抑制因子IkappaB-2， 被 P-选择素和 RANTES 激活。 第三个具体目标将 确定 P-选择素和 RANTES 是否调节 p70 S6 激酶活性 单核细胞。 p70 S6 激酶已知可翻译调节许多 蛋白质和其他证据还表明 p70 S6 激酶可以 调节 NF-κB 家族成员。初步结果表明 p70 S6 暴露于 P-后单核细胞中的激酶活性增加 选择素和 RANTES 或活化的血小板。 此外，抑制p70 雷帕霉素的 S6 激酶活性减弱单核细胞的 MCP-1 分泌 暴露于活化的血小板。 在最终的具体目标中，相关 确定 P-选择素和 RANTES 是否位于破裂区域的研究 颈动脉斑块将得到协调。 综合起来，这些结果 将开始定义如何通过 P-选择素和 RANTES，诱导单核因子合成。