DNA PROBES FOR THE DIAGNOSIS OF PERIODONTAL PATHOGENS

特定细菌作为牙龈炎病原体的作用， 越来越多的科学文献支持牙周炎。 然而，在这方面， 传统的微生物学技术限制了疾病的进展 诊断和监测。 第一期工程的目的是 从细菌的染色体DNA中开发DNA探针， 牙龈炎和牙周炎。 探针将用32 P标记， 与固定在硝酸纤维素上的细菌DNA杂交。 的 每种探针的杂交特异性将在标准品中进行评价 氯化钠溶液，并在一个新的盐溶液，四乙基氯化铵 （TEACl）。 这种新的盐体系取消了A-T的优先熔融 与DNA杂交中的G-C碱基对相比， 熔融曲线的锐化（TEACl中小于1C，NaCl中为5- 10 C） 并增强探针的特异性。 TEACl盐中的DNA探针 该系统将允许开发高度敏感和特异的DNA 用于检测、计数和监测病原体的探针测定 细菌 这个项目的长期目标是提供一个简单的， 快速、准确和低成本的检测方法， 鉴定患者临床分离株中存在的细菌 牙龈炎或牙周炎。 特定病原体的诊断试验 将被开发和商业化生产，用于临床诊断 实验室和牙科诊所。

The role of specific bacteria as the etiologic agents of gingivitis and periodontitis is supported by a growing scientific literature. However, conventional microbiological techniques have restricted advances in disease diagnosis and monitoring. The purpose of this Phase I project is to develop DNA probes from the chromosomal DNA of bacteria associated with gingivitis and periodontitis. The probes will be labeled with 32P and hybridized against bacterial DNA immobilized on nitrocellulose. The hybridization specificity of each probe will be evaluated in the standard NaCl solution, and in a new salt solution, tetraethylammonium chloride (TEACl). This new salt system abolishes the preferential melting of A-T versus G-C base pairs in DNA hybrids, thus producing a significant sharpening of the melting profile (less than 1C in TEACl vs. 5-10C in NaCl) and enhancing the specificity of the probes. DNA probes in a TEACl salt system will allow the development of highly sensitive and specific DNA probe assays for the detection, enumeration and monitoring of pathogenic bacteria. The long-term objective of this project is to provide a simple, rapid, accurate and low-cost methodology for the detection and identification of the bacteria present in clinical isolates from patients with gingivitis or periodontitis. Diagnostic tests for specific pathogens will be developed and produced commercially for use by clinical diagnostic laboratories and in the dental office.