| Schistosomiasis is a infectious and parasitic disease of humans and mammals which is caused by Schistosoma japonicum. The symptoms of the disease are hepatauxe,emaciation,anemia,splenomegaly,edema and ascites. Human or cattle would result in death if could not be treated in time.The traditional pathogenic examination methods for schistosomiasis are stool smear for microscope and miracidia hatching method(MHM), these methods are inexpensive and simple, but labor-intensive, time-consuming and need experienced stuff. The ir low sensitivity limited its use for the diagnosis in the field.There are various immunological detection methods for schistosome infection. For example:indirect haemaglutination test, enzyme-linked immunosorbent assay, immunomagnetic beads technique, dipstick dye immunoassay. These methods are useful for epidemiological study because of its convenience. Immunological detection of schistosome infection also suffers from low sensitivity of the assays, as well as the fundamental problem of persistent antibodies after chemotherapy even though egg counts and circulating antigens. So these methods can not differentiate the primary and post infection, so it can not be used for therapeutic evaluation.RNA binding-protein play an important role in the posttranscriptional modification of the gene expression, it participates in the RNA montage, transport and keep the balance of the RNA steady and degradation. Some of RNA binding protein is highly conservative intraspecifically.A rapid, simple and sensitive technique called loop-mediated isothermal amplification (LAMP) was developed by Notomi et al. which did not require expensive equipment. This method enables the amplification of a few copies of DNA to attain 109 copies in less than 1 h under isothermal conditions and the amplification products are observed visually. The use of four LAMP primers which are designed to recognize six distinct regions on the target gene assures specific amplification.LAMP assays have been developed for the detection of various pathogens, including virus, bacterial and protozoon of animals. It also be used for detecting the transgene soy bean and differentiate gender of fetus of animals.This study developed a LAMP assay and PCR method for detecting S. japonicum-specific DNA in fecal samples based on rbp gene of S. japonicum. We find the LAMP assay has higher sensitivity than the conventional PCR method, which can detect 1.25 eggs/gram feces equivalently through the animal experiment. We do not find the cross-activity of LAMP assay for the common pathogens of cattle, including:Babesia oriental, Theileria spp, indicating that LAMP assay has high specificity.We use the rabbits infected with cerceria for the animal experiment, fecal samples were collected and the DNA of S. japonicum eggs was extracted. We used the MHM, PCR and LAMP assays for detecting S. japonicum egg DNA in feces of internal of rabbits. The LAMP assay was also highly specific for S.japonicum and able to detect S.japonicum DNA in rabbit feces on 35th day post-infection. Whereas the PCR assay and traditional miracidia hatching method detected positive results on 38th day and 41st day p.i., respectively, indictiving that LAMP assay can detect S. japonicum eggs in fecal samples earlier.And we also use the enzyme-linked immunosorbent assay established our laboratory for detecting antibody of the infectious rabbits. The result suggest that antibody can convert to positive 3 weeks after infection, keep at high level and turn negative until 20 weeks gradually.Finally, we use MHM, LAMP and PCR assays for detecting the field samples collected from the epidemic areas of S. japonicum of Hubei and Hunan provinces. Out of 82 clinical stool samples analyzed,2 (2.44%) and 3 (3.7%) were found positive for S. japonicum by MHM and PCR, respecitively, while LAMP detected positive from 9(11%) samples.In conclusion, owning to the easy performance, rapid reaction and low cost, LAMP may therefore be applied as a detecting kit.
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