IRON ACQUISITION BY H CAPSULATUM, AND AIDS OPPORTUNIST

H Capsulatum 获取铁和艾滋病机会主义者

• 批准号: 2004823
• 负责人: DEXTER H HOWARD
• 金额: $ 17.94万
• 依托单位: UNIVERSITY OF CALIFORNIA LOS ANGELES
• 依托单位国家: 美国
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-09-15 至 1998-09-14
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2004823
• 关键词: AIDS; histoplasmosis; host organism interaction; iron metabolism; laboratory mouse; membrane proteins; opportunistic infections; siderophores; tissue /cell culture; virulence

DESCRIPTION: (Adapted from Applicant's Abstract). Disseminated histoplasmosis occurs in a large percentage of AIDS patients who reside in highly endemic areas. The zoopathogenic fungus Histoplasma capsulatum requires iron for growth and like other pathogens must cope with the iron-limiting environment of the host. Since H. capsulatum is a facultative intracelllular parasite, it must rely on the iron reserves of the phagocyte. The long term goal of this work is to study the intracellular nutrition and metabolism of H. capsulatum for the purpose of understanding how intracellular growth of the fungus is interrupted in the macrophages of a recovering host. The goal of the work proposed in this grant is to study aspects of iron acquisition by H. capsulatum. There are three specific aims. (1) Hydroxymate siderophore production of the fungus will be monitored in vitro and following its infection in a murine macrophage cell line and in human monocytes. (2) Histoplasma membrane protein profiles will be revealed again in both in vitro grown organisms, incubated with and without iron sources, as well as following infection in the two populations of macrophages indicated in specific aim 1. The applicant will specifically look for protein alterations induced in the fungus by an iron-restrictive environment. Protein profiles will be examined by standard gel techniques and Western blotting. (3) Mutants of the fungus in hydroxymate siderophore production will be sought using restriction enzyme mediated integration (REMI), a technique similar in principal to transposon mutagenesis. The virulence of such mutants will be tested by their ability to grow in macrophages and by determining their virulence in a murine model of the infection. Such studies may lead to a more effective therapy in histoplasmosis by interrupting the supply of iron to the organism.

描述：（改编自申请人的摘要）。传播 组织胞浆病发生在很大一部分的艾滋病患者中 在高度流行的地区。浮食性真菌组织囊肿 需要铁才能生长，就像其他病原体一样必须应对 宿主的铁限制环境。由于H. capsulatum是 辅助细胞内寄生虫，必须依靠铁为储量 吞噬细胞。 这项工作的长期目标是研究 为此目的 了解真菌的细胞内生长如何中断 在恢复宿主的巨噬细胞中。 提出的工作的目标 在这笔赠款中是研究H. capsulatum的铁采集方面。 有三个特定的目标。 （1）羟基甲酸盐铁载体的产生 真菌将在体外进行监测，并在感染中 鼠巨噬细胞系和人单核细胞中。 （2）组织肿瘤 膜蛋白轮廓将在两种体外生长中再次揭示 有和没有铁源的生物，以及遵循 特定目标中指示的两个巨噬细胞中的感染 1。申请人将特别寻找诱发的蛋白质改变 在真菌中，铁限制性环境。 蛋白质特征会 通过标准凝胶技术和蛋白质印迹进行检查。 （3）突变体 羟基甲酸盐的铁载体生产中的真菌的生产将被寻求 限制酶介导的整合（REMI），这是一种类似的技术 转座子诱变的主。这种突变体的毒力将 通过其在巨噬细胞中成长的能力和确定的能力来测试 它们在感染的鼠模型中的毒力。 这样的研究可能 通过中断，导致在组织胞浆中更有效的疗法 铁向有机体供应。