IRF-1 AND PROLACTIN IN T CELL ACTIVATION

T 细胞激活中的 IRF-1 和催乳素

• 批准号: 2143934
• 负责人: LI-YUAN YU-LEE
• 金额: $ 17.18万
• 依托单位: BAYLOR COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-03-01 至 1999-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2143934
• 关键词: T lymphocyte; biological signal transduction; cell cycle; cytokine; gene expression; genetic promoter element; genetic regulatory element; immunomodulators; laboratory mouse; laboratory rabbit; leukocyte activation /transformation; lymphocyte proliferation; oncoproteins; polymerase chain reaction; prolactin; tissue /cell culture; transcription factor

The peptide hormone prolactin (PRL) exerts a profound effect on both cellular proliferation and differentiation in a variety of tissues, but its role as an immunomodulator has not been well-defined. That PRL plays a potentially important role as a novel T and B cell cytokine has been strengthened by the observations that the PRL receptor (PRL-R), a member of the cytokine receptor superfamily, is expressed on cells of the immune system, and that some of these cells also synthesize and secrete biologically-active PRL. The long-term objective of this proposal is to understand the immunoregulatory properties of PRL. As a model system for investigating the role of PRL as a T cell cytokine, we are using the rat Nb2 T lymphoma cells which require PRL for growth. A major target of PRL stimulation in Nb2 T cells is the transcription factor, interferon regulatory factor-1 (IRF-1). In T cells, PRL stimulates the biphasic expression of IRF-1, first during G1 activation, and again over G1/S transition, where its expression is tightly linked to DNA synthesis and subsequent cell proliferation. Our recent studies have implicated the cytokine signaling molecules "signal transducer and activator of transcription" or Stat, and the cell cycle-regulated transcription complex containing retinoblastoma protein (Rb) as possible PRL signaling molecules at the IRF-i promoter. Our working hypothesis is that PRL and its receptors are involved in signaling for G1 activation as well as for S phase progression in activated T cells. Both cytokine and cell cycle signaling molecules are activated at the IRF-I promoter in a biphasic manner. We further suggest that the transcription factor IRF-1 is a nuclear mediator of PRL action during these distinct phases of the T cell cycle. The proposed studies aim to elucidate how cytokine signal transduction may be integrated with cell cycle control signals to regulate IRF-1 expression, and how IRF-1 may be important for T cell activation and proliferation. Studies are proposed to: 1) Characterize the biphasic PRL response at the IRF-1 promoter during G1 versus S phase, and to elucidate how Stat and Rb proteins participate in these responses. Mutational analysis of promoter elements coupled with studies of protein!DNA interactions will help to identify cis-acting elements and the transacting factors important for PRL stimulation of the IRF-1 gene; and 2) Investigate IRF-1 function and PRL action in T cells. CD8+ T cells from thymocytes and splenocytes representing different stages of development will be analyzed as potential targets of PRL immunomodulation. IRF-1 target genes will also be cloned by differential display PCR, as one way of understanding how PRL (a cytokine signal) and IRF-1 (one cytokine target) modulate T cell activation and proliferation. These studies represent a comprehensive molecular, genetic, biochemical and immunological approach to defining how cytokine signals are integrated with cell cycle signals to regulate IRF-1 gene expression in T lymphocytes. Understanding how PRL modulates the biological functions of T cells should elucidate the immunoregulatory properties of PRL, and provide new insights into neuroendocrine-immune system interactions.

肽激素催乳素（PRL）对两者都产生了深远的影响 各种组织中的细胞增殖和分化，但 它作为免疫调节剂的作用尚未明确定义。 PRL播放 作为新型T和B细胞因子的潜在重要作用已经是 通过观察到PRL受体（PRL-R），成员的观察 细胞因子受体超家族的，在免疫细胞上表达 系统，其中一些细胞也合成并分泌 生物活性PRL。该提议的长期目标是 了解PRL的免疫调节特性。作为模型系统 研究PRL作为T细胞细胞因子的作用，我们正在使用大鼠 需要PRL生长的NB2 T淋巴瘤细胞。 PRL的主要目标 NB2 T细胞中的刺激是转录因子，干扰素 调节因子1（IRF-1）。在T细胞中，PRL刺激双相 IRF-1的表达，首先在G1激活期间，然后再次超过G1/S 过渡，其表达与DNA合成紧密相关，并且 随后的细胞增殖。我们最近的研究暗示了 细胞因子信号分子的信号传感器和激活因子的激活因子 转录”或STAT，以及细胞周期调节的转录 含有视网膜细胞瘤蛋白（RB）的复合物作为PRL信号传导 IRF-I启动子的分子。我们的工作假设是PRL和 它的受体参与了G1激活以及 激活的T细胞中的S相进展。细胞因子和细胞周期 在双相中，在IRF-I启动子处激活信号分子 方式。 我们进一步建议转录因子IRF-1是一个 在T细胞的这些不同阶段，PRL作用的核介质 循环。 拟议的研究旨在阐明细胞因子信号 转导可能与细胞周期控制信号集成到 调节IRF-1表达，以及IRF-1对T细胞的重要性 激活和增殖。提出了研究：1）表征 在G1相对S期IRF-1启动子处的双相PRL响应， 并阐明STAT和RB蛋白如何参与这些反应。 启动子元素的突变分析以及研究 蛋白质！DNA相互作用将有助于识别顺式作用元素和 交易因子对于PRL刺激IRF-1基因很重要； 2）研究T细胞中IRF-1功能和PRL作用。 CD8+ T细胞 来自代表不同阶段的胸腺细胞和脾细胞 开发将被分析为PRL的潜在目标 免疫调节。 IRF-1靶基因也将被差分克隆 显示PCR，是一种理解PRL（细胞因子信号）和 IRF-1（一个细胞因子靶）调节T细胞激活和增殖。 这些研究代表了全面的分子，遗传，生化 和免疫学方法来定义细胞因子信号的方式 与细胞周期信号集成以调节IRF-1基因表达 T淋巴细胞。了解PRL如何调节生物学功能 T细胞应阐明PRL的免疫调节特性，并且 提供有关神经内分泌 - 免疫系统相互作用的新见解。