HORMONAL CONTROL OF CYTOKINES IN BONE AND MARROW CELLS

骨细胞和骨髓细胞中细胞因子的激素控制

• 批准号: 6098701
• 负责人: STAVROS C. MANOLAGAS
• 金额: $ 19.64万
• 依托单位: UNIV OF ARKANSAS FOR MED SCIS
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-06-01 至 2000-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6098701
• 关键词: androgens; bone development; bone marrow; estrogens; genetic regulatory element; hormone regulation /control mechanism; immunocytochemistry; interleukin 6; laboratory mouse; monoclonal antibody; osteoblasts; osteoclasts; polymerase chain reaction; tissue /cell culture; transcription factor

Work leading to this application indicates that the IL-6 gene is transcriptionally regulated by both classes of sex steroids and plays a critical role in the bone loss of gonadal function; that estrogens and androgens also downregulate the expression of the ligand-binding and the signal transducing components of the IL-6 receptor; and that their loss enhances the responsiveness of osteoclast precursors to IL-6 and IL-11, and upregulates osteoblast development. Based on this evidence, it is proposed that IL-6, and other members of the cytokine subfamily that share gp130 for the transduction of their signals, are capable of stimulating not only osteoclast, but also osteoblast, development. The production of IL-6, as well as the action of IL-6 and the action of other members of this cytokine subfamily, is under the inhibitory control of sex steroids. Removal of these inhibitory effects contributes to the increased bone remodeling and the bone loss associated with loss of gonadal function. To test this hypothesis, the mechanism(s) underlying the downregulating effects of estrogens and androgens on the transcription of the genes for IL-6, the ligand-binding subunit of the IL-6 receptor (gp80), and the signal transducing subunit (gp130) will be elucidated by identifying the cis-acting regulatory elements involved and their corresponding transcription factors. Further, the effects of sex steroids on the production of the soluble IL-6 receptor will be studied and cells expressing the mRNAs for IL-6, gp80 and gp130 in ex vivo murine bone marrow cultures and undecalcified cancellous bone sections from sex steroid replete and sex steroid deficient mice will be identified, using in situ RT-PCR in combination with immunohistochemistry. In addition, the role of the IL-6 subfamily of cytokines in the upregulation of osteoblast progenitor formation in the bone marrow following loss of sex steroids, and potential interactions between these cytokines and other growth factors on osteoblastogenesis will be investigated. Finally, chimeric constructs of the soluble IL-6 or CNTF receptor alpha, complexed with monoclonal antibodies recognizing cell surface markers, will be used to selectively direct the corresponding cytokines to either osteoclast or osteoblast progenitors; and investigate the effects of such manipulation on osteoclastogenesis and osteoblastogenesis.

导致此应用的工作表明IL-6基因是 通过两类性类固醇和玩具的转录调节 在性腺功能的骨骼损失中的关键作用；那个雌激素和 雄激素还下调了配体结合的表达和 IL-6受体的信号转导组件；他们的损失 增强破骨细胞前体对IL-6和IL-11的反应性， 并上调成骨细胞的发展。 基于这些证据，是 提出IL-6和其他分享的细胞因子亚家族成员 GP130用于转导信号，能够刺激 不仅是破骨细胞，而且是成骨细胞的发展。 生产 IL-6，以及IL-6的行动和其他成员的行动 这种细胞因子亚家族受到性类固醇的抑制作用。 去除这些抑制作用会导致骨骼增加 重塑和与性腺功能损失相关的骨质流失。 到 检验该假设，即下调的基础机制 雌激素和雄激素对基因转录的影响 IL-6，IL-6受体（GP80）的配体结合亚基， 信号转导亚基（GP130）将通过识别来阐明 顺式作用调节元素及其相应 转录因子。 此外，性类固醇对 将研究可溶性IL-6受体的产生和细胞 在离体鼠骨中表达IL-6，GP80和GP130的mRNA 骨髓培养物和性别不足的取消骨切片 将使用类固醇余和性类固醇缺乏小鼠，使用 原位RT-PCR与免疫组织化学结合使用。 另外， 细胞因子的IL-6亚家族在成骨细胞上调中的作用 性类固醇失去后骨髓中的祖细胞形成， 这些细胞因子与其他生长之间的潜在相互作用 将研究成骨细胞生成的因素。 最后，嵌合 可溶性IL-6或CNTF受体α的构建体，与 识别细胞表面标记的单克隆抗体将用于 选择性地将相应的细胞因子定向到破骨细胞或 成骨细胞祖细胞；并研究这种操纵的影响 在破骨细胞生成和成骨细胞生成上。