Primary culture of cat intestinal epithelial cell and construction of its cDNA library / 中国血吸虫病防治杂志

Objective To establish the primary cat intestinal epithelial cells(IECs)culture methods and construct the cD-NA library for the following yeast two-hybrid experiment,so as to screen the virulence interaction factors among the final host. Methods The primary cat IECs were cultured by the tissue cultivation and combined digestion with collagenase XI and dispase I separately. Then the cat IECs cultured was identified with the morphological observation and cyto-keratin detection ,by using goat anti-cyto-keratin monoclonal antibodies. The mRNA of cat IECs was isolated and used as the template to synthesize the first strand cDNA by SMARTTM technology,and then the double-strand cDNAs were acquired by LD-PCR,which were subsequently cloned into the plasmid PGADT7-Rec to construct yeast two-hybrid cDNA library in the yeast strain Y187 by homologous recom-bination. Matchmaker?Insert Check PCR was used to detect the size distribution of cDNA fragments after the capacity calcula-tion of the cDNA library. Results The comparison of the two cultivation methods indicated that the combined digestion of colla-genase XI and dispase I was more effective than the tissue cultivation. The cat IECs system of continuous culture was established and the cat IECs with high purity were harvested for constructing the yeast two-hybrid cDNA library. The library contained 1.1× 106 independent clones. The titer was 2.8 × 109 cfu/ml. The size of inserted fragments was among 0.5-2.0 kb. Conclusion The yeast two-hybrid cDNA library of cat IECs meets the requirements of further screen research,and this study lays the foundation of screening the Toxoplasma gondii virulence interaction factors among the cDNA libraries of its final hosts.

Prokaryotic expression and identification of rhoptry protein 38 of Toxoplas-ma gondii / 中国血吸虫病防治杂志

Objective To explore the biological function of rhoptry protein 38(ROP38)of Toxoplasma gondii,and to iden?tify the reactogenicity of the recombinant protein(rROP38). Methods The ROP38 was amplified by RT?PCR from T. gondii RH strain,and was cloned into prokaryotic expression vector pET?28a(+). The recombinant plasmid was transformed into E. co?li BL21(DE3)competent cells. Then the rROP38 was analyzed by SDS?PAGE and identified by Western blot. Results SDS?PAGE showed that rROP38 was efficient expression with a molecular weight of about 43 kD. Western blot showed that rROP38 reacted with antibody of His tag or human positive antibody,which indicated that ROP38 had good reactogenicity and could be a serological diagnostic antigen. Conclusion The study successfully obtains the rROP38 of T. gondii with good reactogenicity.

Construction and identification of pcDNA3-HBsAg-p30-ROP2 expression vec-tor / 中国血吸虫病防治杂志

Objective To construct a multi-gene recombinant pcDNA3-HBsAg-p30-ROP2 expression vector and identify it preliminarily. Methods According to recombinant pcDNA3-p30-ROP2 restriction sites,HBV HBsAg gene sequences of primers were designed and synthesized to amplify target fragment,and then cloned into pcDNA3-HbsAg-p30-ROP2 expression vector. Af-ter sequencing,it was identified finally by restriction enzyme digestion and other molecular biology techniques. Results HBV HBsAg gene segment was amplified by PCR and the multi-gene recombinant pcDNA3-HBsAg-p30-ROP2 expression vector was constructed and identified to be correct as theoretical values. The PCR and restriction enzyme digestion results showed that HBsAg and p30-ROP2 gene in recombinant plasmid were confirmed by DNA sequencing. Conclusion The multi-gene recombinant pcD-NA3-HBsAg-p30-ROP2 expression vector is successfully constructed.