[Investigation of two blood parasitic protozoa infection in farmed Macaca fascicularis in Guangxi Zhuang Autonomous Region].

OBJECTIVE: To investigate the infection situation of blood parasitic protozoa in farmed Macaca fascicularis in an animal breeding ground in Nanning, Guangxi Zhuang Autonomous Region, so as to provide the evidence for the prevention and control of human blood parasitic protozoa. METHODS: A total of 993 blood samples from farmed M. fascicularis were collected and stored on FTA cards. Among them, 550 thin blood smears were made. Each 10 samples were mixed in groups, and then the Babesia spp. and Plasmodium spp. in the blood of M. fascicularis were detected by Nest-PCR and PCR, respectively. The positive groups were tested individually. The thin blood smears stained with Giemsa were examined microscopically when PCR reported the samples were positive. RESULTS: When detected by Nest-PCR, the positive rate of Babesia. microti was 6.95% (69/993); only 1 positive sample with Plasmodium inui was detected by PCR. Among the 22 positive thin blood smears detected by PCR, 16 were determined with B. microti by microscopic examinations, on which the ring forms could be observed in the erythrocytes, but no hemozoin. CONCLUSIONS: The positive rate of B. microti in M. fascicularis in Guangxi Zhuang Autonomous Region is high, and the animal may play a role as a reservoir host in the transmission of B. microti. In the screening of B. microti with low infection density, Nest-PCR has a higher sensitivity.

[Cloning and characterization of ß-carbonic anhydrase, a potential drug target of Schistosoma japonicum].

OBJECTIVE: To express the beta carbonic anhydrase (ß-CA) of Schistosoma japonicum, and analyze its catalytic activity. METHODS: The cDNA and amino sequence which may encode ß-CA of S. japonicum were obtained by the bioinformatics-method, and then the cDNA sequence was cloned into prokaryotic expression vector pET-32a (+) and expressed. After examining by SDS-PAGE and Western blotting, the recombinant protein was purified by Ni-affinity chromatography and the catalytic activity was determined. RESULTS: The sequence Sjp_0056790.1 took on the conservative position of ß-CAs. The PCR and restriction enzyme digestion confirmed the construction of recombinant plasmid pET-32a (+) -SjaCA. SDS-PAGE and Western blotting analyses showed that the molecular weight of recombinant protein was about 38 kDa as expected, and it could be recognized by anti-His tag antibody. The catalytic activity determining revealed that the recombinant protein SjaCA owned the carbonic anhydrase activity. CONCLUSIONS: Sjp_0056790.1 encodes the ß-CA of S. japonicum, and the ß-CA with catalytic activity is successfully expressed, so it lays a foundation for the subsequent research of pharmacological inhibition, providing theoretic basis for searching and developing a new feasible anti-schistosome drug.

Prokaryotic expression, purification of prM of JEV and preparation of monoclonal antibody / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To prepare monoclonal antibody (mAb) against prM epitope.</p><p><b>METHODS</b>The gene encoding prM was isolated using RT-PCR from brain of JEV infected mouse and cloned into prokaryotic expression vector pET-32a. Recombinant plasmid was transformed into E.coli BL21/DE3/LysS, then the transformed cells were expressed with the induction of IPTG. The expression and purification of the prM protein was analyzed by SDS-PAGE. The BALB/c mice were immunized with purified prM protein. Hybridoma cell lines secreting monoclonal antibodies against prM were established after cell fusion of mouse splenic cell and P3-X63-Ag8.653 cells. The specificity of mAb was identified by ELISA, Western Blot and Immunohistochemistry assay.</p><p><b>RESULTS</b>mAb against prM epitope of JEV was prepared successfully.</p><p><b>CONCLUSION</b>The obtained prM specific mAb was valuable for the prevention and dignosis of Japanese encephalitis.</p>