MOLECULAR PATHOLOGY OF PNEUMOCYSTIS PNEUMONIA

描述：来自卡氏肺孢子虫感染宿主的肺泡巨噬细胞， 吞噬功能缺陷和转录因子的表达 这些细胞中的加塔-2被严重下调。引入 加塔-2特异性反义寡核苷酸进入正常人肺泡巨噬细胞 未感染的动物也导致了 这些细胞。在这项拟议的研究中，将进行实验，以进一步 探讨加塔-2在肺泡巨噬细胞吞噬中的作用。A加塔-2 将表达载体导入来自P. 卡氏虫感染宿主，以研究加塔-2过表达是否可以 纠正缺陷。为了进一步了解加塔-2在P. 在卡氏病发病机制中，单核细胞中受加塔-2调节的基因将被 鉴定DNA微阵列将用来自野生型和 加塔-2敲除单核细胞。然后分析杂交的微阵列， 确定哪些基因受加塔-2调控。实验也将 以确定是否存在编码MMR，MIP-1 α， MCP-1、IL-6和TNF-α与肺泡上皮细胞功能相关 巨噬细胞受加塔-2调节。卡氏肺孢子虫引起 将探索肺泡巨噬细胞中加塔-2的下调。正常 肺泡巨噬细胞将直接或间接与活的或死的 卡氏肺孢子虫生物体，以确定卡氏肺孢子虫蛋白是否负责 用于下调加塔-2转录，从而导致细胞凋亡减少。 肺泡巨噬细胞的吞噬活性。蛋白质如玻连蛋白， 纤连蛋白、表面活性蛋白A和D以及卡氏肺孢子虫主表面 糖蛋白，这是已知的相互作用与肺泡巨噬细胞在P。 卡氏杆菌感染，亦会接受检查。这些蛋白质将被孵化 单独或与正常巨噬细胞组合，以确定是否 它们对加塔-2下调有任何影响。不同级分 来自卡氏肺孢子虫感染的肺的支气管肺泡灌洗液也将被 测试.任何卡氏肺孢子虫或宿主蛋白被发现具有以下能力： 下调加塔-2表达将通过对一部分 蛋白质。

DESCRIPTION: Alveolar macrophages from Pneumocystis carinii-infected hosts are defective in phagocytosis, and the expression of the transcription factor GATA-2 in these cells is severely down-regulated. Introduction of a GATA-2-specific antisense oligonuceotide into alveolar macrophages from normal uninfected animals also resulted in a decrease in the phagocytic activity of these cells. In this proposed study, experiments will be performed to further investigate the role of GATA-2 in alveolar macrophage phagocytosis. A GATA-2 expression vector will be introduced into alveolar macrophages from P. carinii-infected hosts to investigate whether GATA-2 over-expression could correct the defect. To further understand the involvement of GATA-2 in P. carinii pathogenesis, genes that are regulated by GATA-2 in monocytes will be identified. DNA microarrays will be probed with labeled cDNA from wild type and GATA-2 knockout monocytes. The hybridized microarrays will then be analyzed to determine which genes are regulated by GATA-2. Experiments will also be performed to determine whether genes such as those encoding MMR, MIP-1alpha, MCP-1, IL6 and TNF-alpha that are associated with functions of alveolar macrophages are regulated by GATA-2. The mechanisms by which P. carinii causes down regulation of GATA-2 in alveolar macrophages will be explored. Normal alveolar macrophages will be incubated directly or indirectly with live or dead P. carinii organisms to determine whether a P. carinii protein is responsible for down regulation of GATA-2 transcription leading to a reduction in the phagocytic activity of alveolar macrophages. Proteins such as vitronectin, fibronectin, surfactant proteins A and D, and P. carinii major surface glycoprotein, which are known to interact with alveolar macrophages during P. carinii infection, will also be examined. These proteins will be incubated either alone or in combination with normal macrophages to determine whether they have any effect on GATA-2 down regulation. Different fractions of bronchoalveolar lavage fluids from P. carinii-infected lung will also be tested. Any P. carinii or host protein that is found to have the ability to down regulate GATA-2 expression will be identified by sequencing a portion of the protein.