Development of a highly sensitive nucleic acid amplification-based detection for human leptospirosis infection

Abstract

The availability of highly sensitive diagnostic tools is crucial for individual screening during the epidemic of leptospirosis. A new approach was evaluated to target lipL32 gene amplification that combines a conventional quantitative polymerase chain reaction (qPCR) approach and strand displacement isothermal amplification (qPCDR). The gene target used in this study was LipL32 genes. The qPCDR and qPCR reactions carried out with SD polymerase and taq polymerase, respectively. The results showed that qPCDR technique presented higher sensitivity than qPCR (can detect 2 copies/µL vs. 20 copies/µL) . Evaluation of qPCDR using pathogenic Leptospira DNA diluted with human DNA samples showed at least ten-fold more sensitive than qPCR assays. Therefore, the qPCDR-based technique developed in this study is a promising approach for pathogenic Leptospira detection and further diagnostic kit development.