Sensitive and rapid detection of Schistosoma japonicum DNA by loop-mediated isothermal amplification (LAMP)

• Published in: International journal for parasitology 2010-03, Vol.40 (3), p.327-331
• Main Authors: Xu, J., Rong, R., Zhang, H.Q., Shi, C.J., Zhu, X.Q., Xia, C.M.
• Format: Article
• Language: English
• Subjects: Animals; Biological and medical sciences; DNA, Helminth - genetics; DNA, Helminth - isolation & purification; Early diagnosis; Feces - parasitology; Fundamental and applied biological sciences. Psychology; Humans; Life cycle. Host-agent relationship. Pathogenesis; Loop-mediated isothermal amplification (LAMP); Nucleic Acid Amplification Techniques - methods; Parasitology - methods; Protozoa; Rabbits; Schistosoma japonicum; Schistosoma japonicum - genetics; Schistosoma japonicum - isolation & purification; Schistosomiasis; Schistosomiasis japonica - diagnosis; Schistosomiasis japonica - parasitology; Sensitivity and Specificity; Serum - parasitology; Therapy evaluation; Time Factors
• ISSN: 0020-7519; 1879-0135
• DOI: 10.1016/j.ijpara.2009.08.010

In this study, a loop-mediated isothermal amplification (LAMP) assay was established to detect Schistosoma japonicum DNA in faecal and serum samples of rabbits, and serum samples of humans infected with S. japonicum. This LAMP assay was based on the sequence of highly repetitive retrotransposon SjR2, and was able to detect 0.08 fg S. japonicum DNA, which is 10 4 times more sensitive than conventional PCR. The LAMP assay was also highly specific for S. japonicum and able to detect S. japonicum DNA in rabbit sera at 1 week p.i. Following administration of praziquantel, detection of S. japonicum DNA in rabbit sera became negative at 12 weeks post-treatment. These results demonstrated that LAMP was effective for early diagnosis of, and evaluation of therapy effectiveness for, S. japonicum infection. Both PCR and LAMP assays were then used to detect S. japonicum DNA in 30 serum samples from S. japonicum-infected patients and 20 serum samples from healthy persons. The percentage sensitivity of LAMP was 96.7%, whereas that of PCR was only 60%, indicating that LAMP was more sensitive than conventional PCR for clinical diagnosis of schistosomiasis cases in endemic areas. The established LAMP assay should provide a useful and practical tool for the routine diagnosis and therapeutic evaluation of human schistosomiasis.