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.

导致该应用的工作表明 IL-6 基因是 受两类性类固醇的转录调节，并发挥作用 性腺功能骨质流失的关键作用；雌激素和 雄激素还下调配体结合和配体结合的表达 IL-6受体的信号转导成分；他们的损失 增强破骨细胞前体对 IL-6 和 IL-11 的反应性， 并上调成骨细胞发育。 根据这个证据， 提出 IL-6 和细胞因子亚家族的其他成员共享 gp130 用于信号转导，能够刺激 不仅是破骨细胞，还有成骨细胞的发育。 生产 IL-6，以及 IL-6 的作用和其他成员的作用 该细胞因子亚家族受到性类固醇的抑制控制。 消除这些抑制作用有助于增加骨量 重塑和与性腺功能丧失相关的骨质流失。 到 检验这个假设，下调背后的机制 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，以及 信号转导亚基（gp130）将通过鉴定 涉及的顺式作用调控元件及其相应的 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 在离体小鼠骨中表达 IL-6、gp80 和 gp130 的 mRNA 来自性别的骨髓培养物和未脱钙的松质骨切片 使用类固醇充足和性类固醇缺乏的小鼠将被识别 原位 RT-PCR 与免疫组织化学相结合。 此外， 细胞因子IL-6亚家族在成骨细胞上调中的作用 性类固醇丧失后骨髓中祖细胞的形成， 以及这些细胞因子和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引导至破骨细胞或 成骨细胞祖细胞；并调查这种操纵的影响 关于破骨细胞生成和成骨细胞生成。