Microbial diagnosis by nucleic acid sandwich hybridization.

Sandwich hybridization is a three-component nucleic acid hybridization method suitable for the identification of microbes. In this method, one specific DNA fragment on solid support acts as catching reagent, and the second reagent is a labeled probe. The labeling of the support is mediated by a specimen nucleic acid homologous to both reagents. Because the specimen is kept in solution, relatively crude specimens not requiring elaborate pretreatments can be tested without background problems. The utility of the method in microbial diagnosis (adenovirus, cytomegalovirus, and Chlamydia trachomatis) has been demonstrated. Increased sensitivity and nonradioactive detection methods will no doubt further extend the applicability of the sandwich hybridization method.