• Biomedical Science Letters
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• v.13 no.1
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• pp.33-38
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• 2007

The aim of this work was to validate a rapid and an accurate method for detecting Mycobacterium leprae in clinical specimens using nested PCR targeting M. leprae-specific repetitive element (RLEP) sequence. The primers were derived from the RLEP sequence which yield a 272 bp outer product and a 230 bp inner product. The specificity and the sensitivity of the nested PCR were compared with those of single PCR for detecting M. leprae using DNAs isolated from reference strain and various species of Mycobacterium. The results showed that the sensitivity of the nested PCR was about 100 to 1,000 times higher than that of the single PCR and also showed that both the single and the nested PCR were highly specific to M. leprae. Subsequently, the usefulness of the single and nested PCR was evaluated with clinical samples isolated from leprosy patients. The number of positive detections by the single and the nested PCR with a total of 20 specimens from leprosy patients were 9 (45%) and 20 (100%), respectively. The results clearly showed that nested PCR has highest sensitivity in detecting M. leprae from clinical specimens. Therefore, nested primers targeting RLEP sequence developed in this study seems to be useful to detect the presence of M. leprae.

• Biomedical Science Letters
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• v.16 no.2
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• pp.127-131
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• 2010

Mycobacterium leprae detection is difficult even with molecular biological techniques due to the low sensitivity of current methodologies. In this report, real-time PCR targeting the M. leprae-specific repetitive element (RLEP) sequence was developed as a new diagnostic tool and evaluated using clinical specimens. For this, M. leprae DNAs were extracted from skin biopsy specimens from 80 patients and analyzed by real-time PCR using TaqMan probe. Then, the detection efficiency of the real-time PCR was compared with that of standard PCR. In brief, the rate of positive detection by the standard PCR and real-time PCR was 32.50% and 66.25%, respectively. The results seemed to clearly show that the TaqMan real-time PCR developed in this study may be a useful tool for sensitive detection of M. leprae from clinical specimens.

• Biomedical Science Letters
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• v.13 no.4
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• pp.319-324
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• 2007

One-tube nested polymerase chain reaction (PCR) was evaluated for its efficacy in detecting Mycobacterium leprae in biopsy samples from leprosy patients. Primers were derived from the M leprae-specific element (RLEP) sequences which yield a 230 bp fragment. The specificity and the sensitivity of the one-tube nested PCR were compared with those of single PCR for detecting M leprae. The results showed that the one-tube nested PCR was about 100 times more sensitive than that of the single indicating the one-tube nested primer sets developed in this study can be an effective screening tool for the detection of M leprae in clinical diagnostic laboratories.