Detection of Schistosomia japonicum 5D gene by polymerase chain reaction and genechip technique / 中华流行病学杂志

<p><b>OBJECTIVE</b>In order to develop the diagnostic genechip for specific detection of Schistosoma japonicum (Chinese mainland strain).</p><p><b>METHODS</b>Probe and primers were designed based on the Schistosoma japonicum 5D gene encoding an immunogenic miracidial antigen. The probe for the conservative and specific gene sequence was spotted onto the specially treated glass slides by pin-based spotting robot Pixsys 5500 and was employed to make genechips. A polymerase chain reaction (PCR) protocol was designed to effectively amplify the 5D gene fragment containing the probe sequence from cercaria, egg, adult worm and infected Oncomelania DNA as well as other flukes DNA, respectively. After 35 cycles by PCR, the products were then labeled with fluorescent Cy3-labeled primer, using dissymmetrical PCR. The labeled PCR products of the target genes were hybridized to the diagnostic genechips for detection of Schistosoma japonicum and a fluorescent scanner (ScanArray 3000) was used to observe and record the hybridization signals.</p><p><b>RESULTS</b>The result obtained from the study showed that a 262 bp DNA fragment was amplified from cercaria, egg and adult worm with the designed primers and enable the genechip be applied to detect a single cercaria, egg and adult worm. When the genechip was used to detect Clonorchis sinensis, Fasciolopsis busk, and Paragonimus westermani DNA, the results showed negative, indicating that the genechip had good specificity.</p><p><b>CONCLUSION</b>The genchip technique for detection of Schistosoma japonicum was established successfully and having the characteristics of high sensitivity and specificity.</p>

Construction and Expression of Plasmid Coexpressing Human Papillomavirus Type 11 E7 and Human IFN?-2b / 中华皮肤科杂志

Objective To construct an expression plasmid of human papillomavirus type 11 E7 (HPV11-E7)/hurnan IFN?-2b fusion gene, to express the fusion gene in E.coli BL21, and pave way for further immunological study. Methods The recombinant plasmid was introduced into E.coli BL21, then the expression product was analyzed by SDS-PAGE and Western blotting after induction with isopropy-?-D-thiogalactoside (IPTG). Results The fusion gene of HPV11-E7 and human IFN?-2b was successfully cloned into pET-32a by a linker with the same sequence as we expected. The expressed fusion protein was confirmed by SDS-PAGE and Western blotting. Conclusions The successful construction of prokaryotic expression plasmid and expression of HPV11-E7/human IFN?-2b fusion gene enable further immunological study.