MAMMALIAN CELL CYCLE BLOCK BY A C JEJUNI CYTOTOXIN

空肠杆菌细胞毒素阻断哺乳动物细胞周期

基本信息

批准号：
2887473
负责人：
CAROL L PICKETT
金额：
$ 17.09万
依托单位：
UNIVERSITY OF KENTUCKY
依托单位国家：
美国
项目类别：
财政年份：
1997
资助国家：
美国
起止时间：
1997-07-01 至 2001-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/2887473
关键词：
HeLa cells Helicobacter bacterial disease bacterial toxicology cell growth regulation enterotoxins gastritis gastrointestinal epithelium host organism interaction swine virulence

项目摘要

DESCRIPTION (Adapted from the applicant's abstract): Campylobacter jejuni is the most common bacterial cause of diarrheal disease of humans in the United States. It has recently also been implicated as one of the most common infections to precede the development of Guillain-Barre syndrome. The study of C. jejuni pathogenesis has not yet identified many major virulence factors; in particular, almost nothing is known about the contribution of C. jejuni to disease. The broad long term goal of this proposal are to characterize the interactions of a C. jejuni toxin, called cytolethal distending toxin (CDT) with eukaryotic cells, and to determine the role of CDT in human disease. To date, CDT is the only toxin produced by C. jejuni which has actually been proven to exist. CDT blocks eukaryotic cells in the G2 phase of the cell cycle, an action unlike that of any other known bacterial toxin; and, the predicted amino acid sequence of CDT proteins share no homology with the amino acid sequences of any proteins in the database. The specific aims of the proposal are designed to test the hypothesis that CDT is a virulence factor in C. jejuni diarrheal disease by virtue of its ability to block eukaryotic cells in the G2 phase of the cell cycle. Under aim 1, the ability of the CDT to cause a G2 block in cultured cell line derived from intestinal epithelial cells will be tested. In addition, Dr. Pickett will test whether CDT is active against the cell lines when they are relatively undifferentiated or still proliferating. Under aim 2, the initial interactions of CDT with HeLa cells will be characterized and experiments will be performed to determine if all or a portion of CDT enter the cells. In aim 3, the nature of the G2 block caused by CDT will be examined in greater detail. Under aim 4, the ability of CDT to contribute to C. jejuni diarrheal disease in a piglet model will be tested.

描述（改编自申请人的摘要）：空肠弯曲菌是人类腹泻病最常见的细菌原因美国。它最近也被认为是最严重的问题之一发生格林-巴利综合征之前的常见感染。空肠弯曲菌发病机制的研究尚未确定许多主要的机制毒力因子；特别是，人们对它几乎一无所知空肠弯曲菌对疾病的贡献。该提案的广泛长期目标是描述空肠弯曲菌毒素（称为细胞致死膨胀毒素 (CDT)）的相互作用与真核细胞，并确定 CDT 在人类疾病中的作用。迄今为止，CDT 是空肠弯曲菌产生的唯一已被实际研究的毒素。证明存在。 CDT将真核细胞阻断在细胞的G2期循环，其作用不同于任何其他已知的细菌毒素；并且， CDT蛋白的预测氨基酸序列与数据库中任何蛋白质的氨基酸序列。该提案的具体目标旨在检验以下假设： CDT 是空肠弯曲菌腹泻病的毒力因子，因为它具有能够阻断真核细胞处于细胞周期的 G2 期。在下面目标 1，CDT 在培养细胞系中引起 G2 阻滞的能力来自肠上皮细胞的细胞将被测试。此外，博士。 Pickett 将测试 CDT 是否对细胞系有活性。相对未分化或仍在增殖。在目标 2 下， CDT 与 HeLa 细胞的初始相互作用将被表征并将进行实验以确定是否全部或部分 CDT 进入细胞。在目标 3 中，由 CDT 引起的 G2 块的性质将是更详细地进行了检查。在目标 4 下，CDT 做出贡献的能力将在仔猪模型中测试空肠弯曲菌腹泻病。