MECHANISMS OF T-LYMPHOCYTE DEVELOPMENT

总的目标是定义参与的细胞和分子事件， 胸腺微环境-胸腺细胞相互作用导致正常T细胞 发展或导致异常的T细胞成熟，如在 先天性和获得性T细胞免疫缺陷状态， 恶性肿瘤。 实现这一总体目标所需的研究分为 两个主要领域--上皮细胞的表型和功能特征 人胸腺微环境中的细胞，以及表型和 人T细胞及其前体的功能表征 成熟的阶段。 研究胸腺上皮成熟 人内分泌胸腺上皮的角蛋白亚类将用作 胸腺微环境成熟的标志物。 使用新开发的 胸腺上皮细胞-T细胞结合试验，我们将研究和定义 功能相关的胸腺上皮表面分子， 胸腺上皮-T细胞结合、胸腺激素分泌和 其他免疫调节分子的分泌。 表型和 恶性胸腺上皮细胞（胸腺瘤）的分化能力 与正常和增生性重症肌无力相比，将使用 我们最近开发的长期体外培养人 胸腺上皮 此外，EGF非依赖性转化的胸腺 上皮细胞系将通过引入转化基因来开发 （N-ras，c-Myc）的表达。 使用人 恶性多能干细胞系（DP.528），我们将开发特异性 确定表面或细胞质抗原的单克隆抗体探针 特异于早期（多能干细胞、淋巴样干细胞、定型T细胞 细胞前体，前胸腺细胞）T细胞成熟的阶段。 最后我们 将开发细胞、分子和遗传的体外分析系统， 在T细胞成熟的早期阶段可能发生的事件。 与 这些测定系统、培养的胸腺上皮的作用、其它 辅助细胞，胸腺上皮上清液，合成胸腺激素， 纯化的白细胞介素1或白细胞介素2对分化能力的影响 将研究未成熟的正常和恶性T细胞。

The general goal is to define cellular and molecular events involved in thymic microenvironment-thymocyte interactions that lead to normal T cell development or lead to aberrant T cell maturation, such as is seen in congenital and acquired T cell immunodeficiency states, and in T cell malignancies. The studies required to achieve this general goal fall into two main areas--phenotypic and functional characterization of epithelial cells within the human thymic microenvironment, and phenotypic and functional characterization of human T cells and their precursors at defined stages of maturation. To study thymic epithelial maturation keratin subclasses of human endocrine thymic epithelium will be used as markers of thymic micro-environment maturation. Using a newly developed assay of thymic epithelial-T cell binding, we will study and define functionally relevant thymic epithelial surface molecules with regard to thymic epithelial-T cell binding, secretion of thymic hormones and secretion of other immunoregulatory molecules. The phenotype and differentiating capacity of malignant thymic epithelial cells (thymomas) compared to normal and hyperplastic myasthenia gravis will be studied using our recently developed techniques for long term in vitro growth of human thymic epithelium. In addition, EGF-independent transformed thymic epithelial cell lines will be developed by introducing transforming genes (N-ras, c-Myc) into cultured normal thymic epithelial cells. Using a human malignant pluripotent stem cell line (DP.528), we will develop specific monoclonal antibody probes that define surface or cytoplasmic antigens specific for early (pluripotent stem cell, lymphoid stem cell, committed T cell precursor, prothymocyte) stages of T cell maturation. Finally, we will develop in vitro assay systems for cellular, molecular and genetic events that might transpire during early stages of T cell maturation. With these assay systems, the effects of cultured thymic epithelium, other accessory cells, thymic epithelial supernatants, synthetic thymic hormones, purified Interleukin 1 or Interleukin 2 on the differentiating capacity of immature normal and malignant T cells will be studied.