ISOLATION OF TOXINS FROM C DIFFICILE AND C SORDELLII

艰难梭菌和索氏梭菌中毒素的分离

• 批准号: 3126412
• 负责人: Tracy D. Wilkins
• 金额: $ 13.67万
• 依托单位: VIRGINIA POLYTECHNIC INST AND ST UNIV
• 依托单位国家: 美国
• 财政年份: 1979
• 资助国家: 美国
• 起止时间: 1979-07-01 至 1988-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3126412
• 关键词: Clostridium; antibiotics; antitoxins; bacterial toxins; chemical structure function; colitis; diarrhea; drug adverse effect; enteric bacteria; enterotoxins; enzyme linked immunosorbent assay; feces analysis; hemagglutination test; monoclonal antibody; virulence

Pseudomembranous colitis is a life-threatening disease that is caused indirectly by antibiotic therapy. Physicians now are forced to use large doses of antibiotics to eliminate increasingly resistant pathogens, and such therapy kills many of the beneficial anaerobic bacteria in our colons. In this altered ecosystem, other pathogens can grow and produce toxins that can kill the patient. Clostridium difficile is the most common cause of this antibiotic-associated colitis. This species produces an enterotoxin (toxin A) and a potent cytotoxin (toxin B) both of which appear to be involved in the disease. We have purified both toxins and shown that they are composed of subunits. We will isolate the subunits and define the toxic and binding subunits (if they are different). We have identified a glycoprotein receptor for the enterotoxin, and we also will isolate this receptor. The carbohydrate specificity of the binding site will be determined, and we will define whether this receptor is involved in internalization of the toxin. We will examine the binding of the toxins in vivo to the hamster's colon and in vitro to brush border membranes. The receptor for toxin A will be used in rapid latex agglutination and passive hemagglutination tests to detect the toxin in fecal specimens. Our monoclonal antibodies to toxin A also will be used in such assays, and we will develop monoclonal antibodies for toxin B. We also are developing ELISA tests for other clostridial toxins that may cause antibiotic-associated diarrheas. Once such toxin is the iota toxin of C. spiroforme, which we have found to consist of two synergistic proteins. Toxins A and B of C. difficile also appear to act synergistically, and we will examine the mechanisms involved. Our research will result in a better understanding of colitis and diarrhea resulting from antibiotics and should lead to improved diagnosis.

伪膜性结肠炎是一种危及生命的疾病，由 间接通过抗生素治疗。 医生现在被迫使用大量 使用抗生素剂量来消除日益耐药的病原体，以及 这种疗法杀死了我们体内的许多有益厌氧菌 冒号。 在这个改变的生态系统中，其他病原体可以生长和产生 可以杀死病人的毒素。 艰难梭菌是最常见的 这种抗生素相关性结肠炎的原因。 该物种产生 肠毒素（毒素 A）和强效细胞毒素（毒素 B）均出现 参与该疾病。 我们已经纯化了两种毒素并表明 它们由亚基组成。 我们将分离子单元并定义 有毒和结合亚基（如果它们不同）。 我们已经确定了一个 肠毒素的糖蛋白受体，我们也将分离它 受体。 结合位点的碳水化合物特异性为 确定了，我们将定义该受体是否参与 毒素的内化。 我们将检查毒素的结合 体内为仓鼠结肠，体外为刷缘膜。 这 毒素 A 受体将用于快速乳胶凝集和被动反应 血凝试验检测粪便样本中的毒素。 我们的 毒素 A 的单克隆抗体也将用于此类测定，我们 将开发毒素 B 的单克隆抗体。我们也在开发 ELISA 检测其他可能导致的梭菌毒素 抗生素相关性腹泻。 这种毒素曾经是C.的iota毒素。 螺旋形，我们发现它由两种协同蛋白组成。 艰难梭菌的毒素 A 和 B 似乎也具有协同作用，我们 将检查所涉及的机制。 我们的研究将带来更好的结果 了解抗生素引起的结肠炎和腹泻，并应 从而改善诊断。