CHARACTERIZATION OF CHRONIC, ASYMPTOMATIC INTESTINAL SHEDDING OF SHIGELLA

这些研究针对的是利用特定克隆的毒力基因。 志贺菌作为DNA探针的区域或其序列信息 聚合酶链式反应检测粪便中志贺氏菌。我们的早期 研究表明，DNA探针非常敏感、快速和有效 腹泻患者粪便中志贺氏菌的检测 秘鲁。在最近利用聚合酶链式反应分析的研究中 健康(即无症状)非人类灵长类动物的粪便和它们的 健康的人类照顾者，我们发现慢性病的发生率很高，很低 水平(即低于细菌学检测)无症状携带 志贺氏菌。我们的具体目标是确定(1)这些志贺氏菌 具有完全的毒力潜力，(2)志贺氏菌所处的确切状态 驻留在这些载体中(例如，在粘膜上皮细胞内 冒号？)，(3)携带者对志贺氏菌的免疫状态，以及(4)如果 这种慢性低水平载体状态负责维持 志贺氏菌在美国的地方性流行，目前美国有超过25,000例 每年。

These studies are directed at utilizing specific cloned virulence gene regions of Shigella as DNA probes or their sequence information in polymerase chain reaction assays to detect Shigella in stools. Our early studies showed that DNA probes were very sensitive, quick, and effective in detecting Shigella in the stool of diarrheal disease patients in Peru. In more recent studies utilizing polymerase chain reaction analysis of stools of healthy (i.e. asymptomatic) nonhuman primates and their healthy human caretakers, we have found a high rate of chronic, low level( i.e. below bacteriologic detection) asymptomatic carriage of Shigella. Our specific objectives are to determine (1) if these Shigella have full virulence potential,(2) the exact state in which Shigella are residing in these carriers( e.g. inside mucosal epithelial cells in the colon?), (3) the immune status of the carrier to Shigella, and (4) if this chronic low level carrier state is responsible for maintaining Shigella endemicity in the U.S. where there are now over 25,000 cases per year.