TROPHIC DETERMINANTS OF OLIGODENDROCYTE DEVELOPMENT

少突胶质细胞发育的营养决定因素

• 批准号: 2445780
• 负责人: ANTHONY LORENTZ GARD
• 金额: $ 16.35万
• 依托单位: UNIVERSITY OF SOUTH ALABAMA
• 依托单位国家: 美国
• 财政年份: 1991
• 资助国家: 美国
• 起止时间: 1991-09-30 至 1999-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2445780
• 关键词: astrocytes; cell differentiation; cytokine; genetically modified animals; growth factor receptors; laboratory mouse; laboratory rat; leukemia inhibitory factor; molecular cloning; myelin glycoprotein; neurotrophic factors; oligodendroglia; receptor binding; tissue /cell culture

DESCRIPTION: (Adapted from Applicant's Abstract): This competitive renewal application continues to focus on the search for polypeptide factors regulating growth and survival of differentiating oligodendrocytes (OCs). Dr. Gard has identified two modes of trophic support for cultures of oligodendroblasts purified from postnatal brain by antibody capture. Murine astrocytes specifically release into non-supportive, serumless culture medium a powerful oligodendrogiotrophic stimulus (ACM), polypeptide activity significantly more efficacious than other tested cytokines with OC survival-promoting capacity. The astroglial stimulus effecting long- term OC survival is related immunochemically to leukemia inhibitory factor (LIF) but appears distinct from LIF itself. Hypothesizing that another gp130 transducer-activating cytokine is responsible, LIF homologues produced by astrocytes in addition to astrocyte- derived inflammatory cytokines and neurotrophins will be systematically bioassayed in Aim 1 by Dr. Gard as potential gliotrophins for differentiating OBs, and cultured human astrocytes screened for the release for similar activity. Aim 2 proposes to purify the LIF-like stimulus from rat astrocyte-conditioned culture medium by FPLC and its subsequent cloning if amino acid sequencing indicates a novel factor. In Aim 3, the developmental expression of LIF receptors by antigenically distinct OBs and OCs developing in vitro and in vivo will be examined, and their activation by ACM assessed. Cultured OBs deprived of diffusible growth factors can survive differentiation if presented with specific cell adhesion molecules in the immunoglobulin superfamily, the myelin- associated glycoprotein (MAG) and NCAM, which also promote growth by augmenting myelin-like membrano-genesis. The novel concept of cell contact-mediated signaling at the OC surface contributing oligodendrogliotrophic support will be tested in Aim 4 by quantifying OC death occurring (a) naturally in brains of pre-myelinating mice deficient in MAG or its associated non-receptor tyrosine kinase Fyn, and in (b) response to MAG antibody perturbation in vitro and in vivo. Other in vitro studies will characterize the growth, and response to MAG/NCAM, of immunopurified MAG- and Fyn-deficient OBs and begin to address the possible convergence of cytokine-and cell recognition molecule-mediated oligodendrogliotrophic signaling by MAG- and LIF-receptor activation. Dr. Gard's studies are expected to increase knowledge of the changing scope of myelinogenic signals engaged during OC maturation and should provide insight concerning the etiology of dysmyelinating diseases and prospects for trophic factor therapy.

描述：（改编自申请人的摘要）：这种竞争性更新 应用程序继续专注于搜索多肽因素 调节分化的少突胶质细胞（OCS）的生长和存活。 Gard博士确定了两种对文化的营养支持模式 通过抗体捕获从产后大脑纯化的少突胶质细胞。 鼠 星形胶质细胞专门释放到非支持的无血清培养物中 培养基强大的少突可营养刺激（ACM），多肽活性 与其他OC的其他测试细胞因子相比，明显更有效 生存促进能力。 星形胶质刺激影响长期 OC存活与白血病抑制因子（LIF）有关 但似乎与LIF本身不同。 假设另一GP130 传感器激活细胞因子是造成的，由 星形胶质细胞除了星形胶质细胞的炎症细胞因子和 神经营养蛋白将在Gard博士的AIM 1中系统地生化 潜在的神经营养蛋白，以区分观察和培养的人 星形胶质细胞筛选了释放的类似活动。 目标2提议 净化大鼠星形胶质细胞条件培养基的LIF样刺激 通过FPLC及其随后的克隆，如果氨基酸测序表明 新因素。 在AIM 3中，通过 抗原上不同的OBS和OC在体外和体内发育 检查了及其通过ACM的激活评估。 被剥夺了养殖的观察 如果呈现，可扩散的生长因子可以在分化中生存 免疫球蛋白超家族中的特定细胞粘附分子， 髓磷脂相关的糖蛋白（MAG）和NCAM，这也促进了通过 增强髓鞘状的膜生成。 细胞的新颖概念 接触介导的信号在OC表面促成 通过量化OC，将在AIM 4中测试少突齿植物营养的支持 死亡发生（a）自然存在于脓肿的小鼠的大脑中 MAG或其相关的非受体酪氨酸激酶FYN和（b）反应 在体外和体内进行MAG抗体扰动。 其他体外研究 将表征免疫疗法的生长和对MAG/NCAM的反应 杂志和FYN缺陷obs，并开始解决可能的融合 细胞因子和细胞识别分子介导的少突胶质营养素 通过磁受体和LIF受体激活信号传导。 加德博士的研究是 预计将增加对髓纤维信号范围不断变化的知识 在OC成熟期间参与，应提供有关 营养因素的肿瘤疾病和前景的病因 治疗。