CHARACTERIZATION OF DIFFERENT TYPES OF HUMAN MAST CELLS

已经鉴定了两种不同类型的人肥大细胞， 与主要基于中性蛋白酶的嗜碱性粒细胞不同 其分泌颗粒的组成。MCrc型肥大细胞 含有类胰蛋白酶、糜蛋白酶、组织蛋白酶6样蛋白酶和肥大细胞 羧肽酶; MCr型仅含类胰蛋白酶;嗜碱性粒细胞 含有可忽略不计至检测不到量的这些蛋白酶。每个小区 型也具有特殊的超微结构特征和分布 在他们的主人。 目的1研究人肥大细胞的特殊成分， 嗜碱性粒细胞蛋白聚糖类型将与蛋白聚糖类型一起沿着确定。 类胰蛋白酶和糜蛋白酶蛋白及mRNA在不同类型胃癌中的表达 人肥大细胞和嗜碱性粒细胞。我们希望确定是否成熟， 发育中的MCt和MCrc细胞含有相同的蛋白聚糖种类， 这些肥大细胞亚型是否在糜蛋白酶mRNA含量上不同， 蛋白质含量，以及类胰蛋白酶或糜蛋白酶的原位杂交 mRNA在蛋白质表达前鉴定定型肥大细胞祖细胞 并将活化的肥大细胞与静止的肥大细胞区分开来， 人类嗜碱性粒细胞的一种明显独特的成分。 目标2将研究不同的生长，分化和生存 人类肥大细胞和嗜碱性粒细胞的类型。这些研究部分基于 重要的新发现，干细胞因子（Kit配体）是一个主要的 人肥大细胞生长因子最初的重点将是IL-4， 干扰素α和γ以及各种类固醇。对FcepsilonRI的影响 和Kit表达，对蛋白酶和组胺的影响，以及对MCt的选择性 细胞、MCrc细胞和嗜碱性粒细胞。最后，能力 小鼠和人成纤维细胞完成干细胞成熟 将检查因子依赖性肥大细胞。 目的3将确定不同类型的人肥大细胞的参与 和嗜碱性粒细胞在人类疾病中的作用， 目标。此外，通过一种手段，肥大细胞祖细胞的频率在 外周血可以评估将被设计和用于分析 外周血肥大细胞增生性疾病患者 （系统性肥大细胞增多症）、耗竭（AIDS）和活化（过敏性 鼻炎）。 肥大细胞和嗜碱性粒细胞的更好表征将提供更多 精确的测量和监控手段。它们与人类疾病的关系， 以及更好的治疗干预策略。

Two different types of human mast cells have been identified and distinguished from basophils based primarily on the neutral protease composition of their secretory granules. The MCrc type of mast cell contains tryptase, chymase, cathepsin 6-like protease and mast cell carboxypeptidase; the MCr type contains only tryptase; and basophils contain negligible to undetectable amounts of these proteases. Each cell type also exhibits special ultrastructural features and distributions within their host. Aim 1 will investigate the special constituents of human mast cells and basophils. The proteoglycan type(s) will be determined along with the expression of tryptase and chymase protein and mRNA in different types of human mast cells and basophils. We expect to determine whether mature and developing MCt and MCrc cells contain the same proteoglycan species, whether these mast cell subtypes differ in chymase mRNA content, like protein content, and whether in situ hybridization for tryptase or chymase mRNA identifies committed mast cell progenitors prior to protein expression and distinguishes activated from resting mast cells, and to clone and sequence an apparently unique constituent of human basophils. Aim 2 will examine the growth, differentiation and survival of different types of human mast cells and basophils. These studies are based in part on the important new finding that stem cell factor (Kit ligand) is a major growth factor for human mast cells. Initially the focus will be on IL-4, interferons alpha and gamma and various steroids. Effects on FcepsilonRI and Kit expression, on proteases and histamine, and selectivity for MCt cells, MCrc cells and basophils will be studied. Finally, the capacity of murine and human fibroblasts to complete the maturation of stem cell factor-dependent mast cells will be examined. Aim 3 will determine the involvement of different types of human mast cells and basophils in human diseases, using techniques developed in previous aims. Also, a means by which mast cell progenitor frequency in the peripheral blood can be assessed will be devised and used to analyze peripheral blood patients with diseases with mast cell hyperplasia (systemic mastocytosis), depletion (AIDS) and activation (allergic rhinitis). Better characterization of mast cells and basophils will provide more precise means to measure and monitor. their involvement in human disease, and better strategies for therapeutic interventions.