EFFECTS OF ANDROGENS ON THE THYMUS

雄激素对胸腺的影响

• 批准号: 2141590
• 负责人: Nancy J Olsen
• 金额: $ 13.51万
• 依托单位: VANDERBILT UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-02-01 至 1997-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2141590
• 关键词: RNase protection assay; T lymphocyte; androgen receptor; androgens; antireceptor antibody; apoptosis; autoradiography; cell cycle; cell growth regulation; cell population study; enzyme linked immunosorbent assay; flow cytometry; gene expression; hormone regulation /control mechanism; immunocytochemistry; immunoregulation; implant; laboratory mouse; male castration; polymerase chain reaction; receptor binding; receptor expression; solution hybridization; testosterone; thymus; tissue /cell culture; transforming growth factors

Clinical and experimental observations suggest a role for gonadal hormones in modulation of the immune response. The most likely site of interaction between the immune and endocrine systems is the thymus gland. It has been long recognized that changes in androgen status are associated with changes in thymus size and we have demonstrated the presence of classic androgen receptors (AR) in thymocytes, suggesting that such changes are receptor-mediated. In previous studies, including work supported by this grant, we have used murine models to demonstrate effects of alterations in androgen status on the thymus. Androgen withdrawal and replacement and genetic syndromes of androgen resistance were found to be associated with changes in thymus size, composition and function. We now propose to continue to explore underlying cellular and biochemical mechanisms-with the following specific aims: 1. Identification of the cellular targets of androgen action in the thymus with examination of thymocyte and epithelial portions of the gland. 2. Determination of the role of transforming growth factor beta (TGF-beta) in androgen-mediated thymic involution. 3. Investigation of the role of the following physiologic processes in androgen-mediated thymic involution: A. Acceleration of programmed thymocyte death B. Mediation of thymocyte cell cycle entry Androgen status will be altered in normal male mice by castration with and without testosterone replacement. Cellular targets of androgen action will be identified at the RNA level using a nuclease protection assay for measurement of AR-specific RNA and the reverse transcription/polymerase chain reaction (RT/PCR) to identify AR in thymocytes and thymocyte subsets. Results will be confirmed at the protein level using specific anti-AR antibodies in immunohistochemical studies. Changes in TGF-beta levels with alterations in androgen status will be examined using nuclease protection and RT/PCR assays and confirmed using a specific ELISA and bioassays. Further assessment of whether TGF-beta recapitulates androgen effects will utilize intrathymic administration of TGF-beta. Effects of androgens on programmed cell death will examine DNA fragmentation and nuclease activation. The ability of androgens to alter thymocyte proliferation will be examined by measurement of DNA content, quantitation of cycling thymocytes using flow cytometry and histologic examination of thymus with bromodeoxyuridine and 3H thymidine labeling.

临床和实验观察表明性腺的作用 调节免疫反应的激素。 最可能的网站 免疫和内分泌系统之间的相互作用是胸腺。 长期以来，人们已经认识到雄激素状态的变化是 与胸腺大小的变化相关，我们已经证明了 胸腺细胞中经典的雄激素受体（AR）的存在，表明 这种变化是受体介导的。 在先前的研究中，包括 这笔赠款支持的工作，我们使用了鼠模型来证明 雄激素状态改变对胸腺的影响。 雄激素 抗雄激素耐药性的提取和替代和遗传综合征 发现与百里香大小，成分和 功能。 现在，我们建议继续探索潜在的细胞和 生化机制与以下特定目的： 1。鉴定雄激素作用的细胞靶标 胸腺检查胸腺细胞和上皮部分 腺。 2。确定转化生长因子β的作用 （TGF-beta）雄激素介导的胸腺涉及。 3。调查以下生理过程的作用 雄激素介导的胸腺反应： A.编程胸腺细胞死亡的加速 B.胸腺细胞细胞周期进入的介导 正常雄性小鼠将通过cast割而改变雄激素状态 并且没有睾丸激素替代。 雄激素的细胞靶 将使用核酸酶保护在RNA水平上确定作用 测量AR特异性RNA的测定和反向的测定 转录/聚合酶链反应（RT/PCR）以识别AR 胸腺和胸腺亚胸腺。 结果将在 免疫组织化学中使用特定抗AR抗体的蛋白质水平 研究。 随着雄激素状态的改变，TGF-β水平的变化 将使用核酸酶保护和RT/PCR分析进行检查， 使用特定的ELISA和生物测定确认。 进一步评估 TGF-β是否概括雄激素作用将利用胸膜 TGF-beta的给药。 雄激素对编程单元的影响 死亡将检查DNA片段化和核酸酶激活。 这 雄激素改变胸腺细胞增殖的能力将通过 DNA含量的测量，使用流量的循环胸腺细胞定量 用溴脱氧尿苷和 3H胸苷标记。