EXTRACELLULAR MATRIX ALVEOLAR CELL DIFFERENTIATION

细胞外基质肺泡细胞分化

• 批准号: 3344049
• 负责人: Jeanne Marie Snyder
• 金额: $ 9.38万
• 依托单位: UT SOUTHWESTERN MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 1985
• 资助国家: 美国
• 起止时间: 1985-06-01 至 1989-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3344049
• 关键词: cell differentiation; cortisol; electron microscopy; embryo /fetus; extracellular matrix; gestational age; histochemistry /cytochemistry; histogenesis; hormone regulation /control mechanism; immunofluorescence technique; lung alveolus; mammalian embryology; mesenchyme; radiotracer; respiratory epithelium; tissue /cell culture

An interaction between mesenchyme and epithelium is required for the normal differentiation of many tissues. The extracellular matrix may mediate this interaction. We propose to investigate several aspects of the relationship between lung alveolar epithelial cells and the underlying mesenchyme and extracellular matrix during fetal lung development. These studies will be performed using rabbit lung obtained from fetuses of varying gestational ages, and an in vitro model, day 19 gestational age rabbit fetal lung tissue explants maintained in culture, a model in which type II cell differentiation is predominant. Ultrastructural morphometry will be used to describe changes in the structure of the basal lamina and physical interactions between mesenchyme and epithelium during fetal lung development. The fetal lung extracellular matrix will be described at the various stages of development by use of light and electron microscopic immunohistochemical staining for 2 components of the extracellular matrix, laminin and fibronectin. In correlative biochemical studies, we will determine the rate of synthesis and accumulation of laminin and fibronectin at different stages of fetal lung development. Once we have determined the normal pattern of changes in the extracellular matrix during fetal lung development, we will examine the effect of cortisol, a hormone which is known to accelerate fetal lung development, on the morphological and biochemical parameters described above. In this manner we can determine if cortisol stimulation of fetal lung maturation is mediated, in part, by changes in the mesenchyme and/or extracellular matrix. In addition, dispersed fetal lung cells will be cultured on artificial extracellular matrices produced by lung endothelial cells or fibroblasts as well as on matrices of laminin, fibronectin and/or type IV collagen. In this way we will determine if extracellular matrix components which appear to play an important role during development in vivo are capable of promoting differentiation in a controlled in vitro environment. The results of these studies will provide important information with respect to interactions between extracellular matrix and epithelial cells during differentiation of fetal lung alveolar epithelium and will be relevant to understanding the mechanisms of tissue differentiation in general. A better understanding of the process of normal fetal lung maturation could allow the development of better methods to stimulate the lung of the right risk-fetus in a manner that could serve to prevent RDS after birth.

间充质和上皮细胞之间的相互作用是正常的 许多组织的分化。 细胞外基质可能介导了这一过程 互动 我们建议调查几个方面的关系 肺泡上皮细胞和下面的间质之间， 细胞外基质在胎肺发育中的作用。 这些研究报告将 使用从不同妊娠期胎儿获得的兔肺进行 年龄，和体外模型，胎龄19天兔胎肺 组织外植体保持在培养物中，其中II型细胞 分化占主导地位。 将使用超微结构形态测定法 描述基底层结构的变化， 胎肺发育过程中间充质与上皮的相互作用 发展 胎儿肺细胞外基质将在 利用光学和电子显微镜观察发育的各个阶段 细胞外基质2种成分的免疫组织化学染色， 层粘连蛋白和纤连蛋白。 在相关的生化研究中，我们将 测定层粘连蛋白和纤连蛋白的合成和积累速率 在胎儿肺发育的不同阶段。 一旦我们确定了 胎肺期细胞外基质变化的正常模式 发展，我们将研究皮质醇的影响，一种激素， 已知加速胎儿肺发育，在形态学和 上述生化参数。 通过这种方式，我们可以确定是否 皮质醇刺激胎肺成熟部分是由 间充质和/或细胞外基质的变化。 此外，本发明还提供了一种方法， 将分散的胎肺细胞培养在人工细胞外基质上， 由肺内皮细胞或成纤维细胞产生的基质以及 层粘连蛋白、纤连蛋白和/或IV型胶原的基质。 这样我们 将决定是否细胞外基质成分，似乎发挥作用， 在体内发育过程中重要作用是能够促进 在受控的体外环境中分化。 的结果予以 研究将提供关于相互作用的重要信息 细胞外基质和上皮细胞之间的关系 胎儿肺泡上皮细胞，并将相关的了解， 组织分化的一般机制。 更好地了解 正常的胎儿肺成熟过程可能会导致 更好的方法来刺激右风险胎儿的肺部， 可以预防出生后的RDS。