利什曼原虫的 L ACK抗原是利什曼原虫活性蛋白激酶 C受体同源物 ,是一种新发现的抗原蛋白。我们以本实验室的重组质粒 T- L ACK为模板 ,PCR扩增获得 L ACK基因 ,与真核表达载体 pc DNA3.1(+)定向重组 ,重组质粒经酶切和 PCR分析 ,含有约...利什曼原虫的 L ACK抗原是利什曼原虫活性蛋白激酶 C受体同源物 ,是一种新发现的抗原蛋白。我们以本实验室的重组质粒 T- L ACK为模板 ,PCR扩增获得 L ACK基因 ,与真核表达载体 pc DNA3.1(+)定向重组 ,重组质粒经酶切和 PCR分析 ,含有约 95 0 bp的 L ACK基因 ,成功构建含有 L ACK基因的真核表达重组质粒 pc D-NA3- L ACK。将此重组质粒转染 COS- 7细胞 ,通过 RT- PCR及免疫荧光检测 L ACK基因在真核细胞中的表达。实验结果显示转染了重组质粒的 COS- 7细胞 ,其 RT- PCR及免疫荧光检测均呈阳性反应 ,证实重组质粒 pc DNA3-L ACK能在 COS- 7细胞中有效表达 L ACK蛋白。展开更多
OBJECTIVE: To confirm the existence of point mutations in the SSU rDNA variable regions of 5 Leishmania donovani (L.d.) isolates from different epidemic foci in China. METHODS: Specific SSU rDNA fragments from nuclear...OBJECTIVE: To confirm the existence of point mutations in the SSU rDNA variable regions of 5 Leishmania donovani (L.d.) isolates from different epidemic foci in China. METHODS: Specific SSU rDNA fragments from nuclear DNA of 7 Leishmania species/isolates were amplified by PCR and then cloned into pGEM(R)-T Easy Vectors. After that, the specific fragments were sequenced by an automated DNA sequencer. RESULTS: Sequence analysis showed that the amplified DNA fragments of 7 Leishmania species/isolates were all 392 bp in length. All 5 point mutations were located in two unique sequence blocks (UQ-I and UQ-II), and no insertions or deletions were found. The identities of comparison of Leishmania in GeneBank were more than 98%. CONCLUSION: Five point mutations exist in the SSU rDNA variable region of 5 L.d. isolates from different epidemic foci of visceral leishmaniasis (VL) in China. Sequence differences of the SSU rDNA variable region exist among L.d. isolates from different foci.展开更多
To confirm the existence of point mutations in the SSU rDNA variable regions of 5 Leishmania donovani (L d ) isolates from different epidemic foci in China Methods Specific SSU rDNA fragments from nuclear DNA of 7...To confirm the existence of point mutations in the SSU rDNA variable regions of 5 Leishmania donovani (L d ) isolates from different epidemic foci in China Methods Specific SSU rDNA fragments from nuclear DNA of 7 Leishmania species/isolates were amplified by PCR and then cloned into pGEM R T Easy Vectors After that, the specific fragments were sequenced by an automated DNA sequencer Results Sequence analysis showed that the amplified DNA fragments of 7 Leishmania species/isolates were all 392 bp in length All 5 point mutations were located in two unique sequence blocks (UQ Ⅰ and UQ Ⅱ), and no insertions or deletions were found The identities of comparison of Leishmania in GeneBank were more than 98% Conclusion Five point mutations exist in the SSU rDNA variable region of 5 L d isolates from different epidemic foci of visceral leishmaniasis (VL) in China Sequence differences of the SSU rDNA variable region exist among L d isolates from different foci展开更多
Background The vaccination of mice with DNA encoding single candidate antigens has failed to induce significant protection against Schistosoma japonicum (S. japonicum) challenge infections In this study, we evaluated ...Background The vaccination of mice with DNA encoding single candidate antigens has failed to induce significant protection against Schistosoma japonicum (S. japonicum) challenge infections In this study, we evaluated the feasibility of using a multivalent DNA vaccine which co expressed S japonicum integral membrane protein Sj23 and murine cytokine IL 12 to induce protective immune responses Methods The plasmid pVIVO2 IL12 Sj23, a eukaryotic expression vector expressing Sj23 and murine IL 12 simultaneously, was constructed, identified, and tested for expression in vitro Its ability to protect against S japonicum challenge infections was analyed according to worm reduction rate and egg reduction rate after vaccination of BALB/c mice The serum levels of specific IgG antibody were determined by enzyme linked immuno sorbent assay (ELISA) and Western blot analysis Using cultured spleen cells, IFN γ and IL 4 post stimulation were quantified by ELISA The phenotypes of splenocyte populations were analyzed by flow cytometry (FCM) Results The plasmid DNA pVIVO2 IL12 Sj23 was proven to express well in vitro by transient transfection of HEK 293 cells Immunization resulted in a worm reduction rate of 45 53% and egg reduction rate of 58 35% ELISA and Western blot analysis indicated that immunized mice generated specific IgG against Sj23 Spleen cells showed significant increases in IFN γ but decreases in IL 4 No significant differences in CD4 + and CD8 + subgroup ratios were observed after the challenges Conclusions The multivalent DNA vaccine pVIVO2 IL12 Sj23 is sufficient to elicit moderate but highly significant levels of protective immunity against challenge infections Cytokine IL 12, as a gene adjuvant, was able to enhance the Th1 responses and, hence, the protective immunity展开更多
Background Recently congenital infection with Schistosoma japonicum (S. japonicum) has been domonstrated in pigs, rabbits, mice and dogs. We explored the rabbit as an animal model for the congenital infection of schi...Background Recently congenital infection with Schistosoma japonicum (S. japonicum) has been domonstrated in pigs, rabbits, mice and dogs. We explored the rabbit as an animal model for the congenital infection of schistosomiasis japonica and assessed the effect of a congenital S. japonicum infection on the resistance of rabbit kittens to a postnatal challenge infection.Methods Sixteen pregnant New Zealand white rabbits were infected with a single dose of S. japonicum cercariae. The exposed animals were divided into three groups according to the gestation age at the time of infection. Diagnosis of prenatally acquired S. japonicum infection in the rabbit kittens was primarily based on serological tests in combination with parasitological and histopathological findings. Congenitally infected kittens were challenged percutaneously with 100 S. japonicum cercariae to assess the effect of a congenital S. japonicum infection on kitten resistance to a postnatal challenge infection.Results The overall prevalence of congenital infection in offspring of infected mothers was 20% (12/60). The congenital infection rate in group L (late gestation) was much higher than in group E (early gestation) and group M (mid-gestation) (P<0.05). After a postnatal challenge infection, prenatally infected kittens had a 54.66% worm reduction rate, 41.45% egg reduction rate, and 51.76% granuloma size reduction rate compared to nave kittens.Conclusions This study demonstrates the possibility of congenital infection of S. japonicum in rabbits and the resistance of congenitally infected kittens to a postnatal challenge infection. These results have important implications not only for epidemiological investigations, but also in designing government control programs for schistosomiasis.展开更多
文摘利什曼原虫的 L ACK抗原是利什曼原虫活性蛋白激酶 C受体同源物 ,是一种新发现的抗原蛋白。我们以本实验室的重组质粒 T- L ACK为模板 ,PCR扩增获得 L ACK基因 ,与真核表达载体 pc DNA3.1(+)定向重组 ,重组质粒经酶切和 PCR分析 ,含有约 95 0 bp的 L ACK基因 ,成功构建含有 L ACK基因的真核表达重组质粒 pc D-NA3- L ACK。将此重组质粒转染 COS- 7细胞 ,通过 RT- PCR及免疫荧光检测 L ACK基因在真核细胞中的表达。实验结果显示转染了重组质粒的 COS- 7细胞 ,其 RT- PCR及免疫荧光检测均呈阳性反应 ,证实重组质粒 pc DNA3-L ACK能在 COS- 7细胞中有效表达 L ACK蛋白。
文摘OBJECTIVE: To confirm the existence of point mutations in the SSU rDNA variable regions of 5 Leishmania donovani (L.d.) isolates from different epidemic foci in China. METHODS: Specific SSU rDNA fragments from nuclear DNA of 7 Leishmania species/isolates were amplified by PCR and then cloned into pGEM(R)-T Easy Vectors. After that, the specific fragments were sequenced by an automated DNA sequencer. RESULTS: Sequence analysis showed that the amplified DNA fragments of 7 Leishmania species/isolates were all 392 bp in length. All 5 point mutations were located in two unique sequence blocks (UQ-I and UQ-II), and no insertions or deletions were found. The identities of comparison of Leishmania in GeneBank were more than 98%. CONCLUSION: Five point mutations exist in the SSU rDNA variable region of 5 L.d. isolates from different epidemic foci of visceral leishmaniasis (VL) in China. Sequence differences of the SSU rDNA variable region exist among L.d. isolates from different foci.
基金ThisprojectwassupportedbyagrantfromtheNationalNaturalScienceFoundationofChina (No 39970 667)
文摘To confirm the existence of point mutations in the SSU rDNA variable regions of 5 Leishmania donovani (L d ) isolates from different epidemic foci in China Methods Specific SSU rDNA fragments from nuclear DNA of 7 Leishmania species/isolates were amplified by PCR and then cloned into pGEM R T Easy Vectors After that, the specific fragments were sequenced by an automated DNA sequencer Results Sequence analysis showed that the amplified DNA fragments of 7 Leishmania species/isolates were all 392 bp in length All 5 point mutations were located in two unique sequence blocks (UQ Ⅰ and UQ Ⅱ), and no insertions or deletions were found The identities of comparison of Leishmania in GeneBank were more than 98% Conclusion Five point mutations exist in the SSU rDNA variable region of 5 L d isolates from different epidemic foci of visceral leishmaniasis (VL) in China Sequence differences of the SSU rDNA variable region exist among L d isolates from different foci
文摘Background The vaccination of mice with DNA encoding single candidate antigens has failed to induce significant protection against Schistosoma japonicum (S. japonicum) challenge infections In this study, we evaluated the feasibility of using a multivalent DNA vaccine which co expressed S japonicum integral membrane protein Sj23 and murine cytokine IL 12 to induce protective immune responses Methods The plasmid pVIVO2 IL12 Sj23, a eukaryotic expression vector expressing Sj23 and murine IL 12 simultaneously, was constructed, identified, and tested for expression in vitro Its ability to protect against S japonicum challenge infections was analyed according to worm reduction rate and egg reduction rate after vaccination of BALB/c mice The serum levels of specific IgG antibody were determined by enzyme linked immuno sorbent assay (ELISA) and Western blot analysis Using cultured spleen cells, IFN γ and IL 4 post stimulation were quantified by ELISA The phenotypes of splenocyte populations were analyzed by flow cytometry (FCM) Results The plasmid DNA pVIVO2 IL12 Sj23 was proven to express well in vitro by transient transfection of HEK 293 cells Immunization resulted in a worm reduction rate of 45 53% and egg reduction rate of 58 35% ELISA and Western blot analysis indicated that immunized mice generated specific IgG against Sj23 Spleen cells showed significant increases in IFN γ but decreases in IL 4 No significant differences in CD4 + and CD8 + subgroup ratios were observed after the challenges Conclusions The multivalent DNA vaccine pVIVO2 IL12 Sj23 is sufficient to elicit moderate but highly significant levels of protective immunity against challenge infections Cytokine IL 12, as a gene adjuvant, was able to enhance the Th1 responses and, hence, the protective immunity
文摘Background Recently congenital infection with Schistosoma japonicum (S. japonicum) has been domonstrated in pigs, rabbits, mice and dogs. We explored the rabbit as an animal model for the congenital infection of schistosomiasis japonica and assessed the effect of a congenital S. japonicum infection on the resistance of rabbit kittens to a postnatal challenge infection.Methods Sixteen pregnant New Zealand white rabbits were infected with a single dose of S. japonicum cercariae. The exposed animals were divided into three groups according to the gestation age at the time of infection. Diagnosis of prenatally acquired S. japonicum infection in the rabbit kittens was primarily based on serological tests in combination with parasitological and histopathological findings. Congenitally infected kittens were challenged percutaneously with 100 S. japonicum cercariae to assess the effect of a congenital S. japonicum infection on kitten resistance to a postnatal challenge infection.Results The overall prevalence of congenital infection in offspring of infected mothers was 20% (12/60). The congenital infection rate in group L (late gestation) was much higher than in group E (early gestation) and group M (mid-gestation) (P<0.05). After a postnatal challenge infection, prenatally infected kittens had a 54.66% worm reduction rate, 41.45% egg reduction rate, and 51.76% granuloma size reduction rate compared to nave kittens.Conclusions This study demonstrates the possibility of congenital infection of S. japonicum in rabbits and the resistance of congenitally infected kittens to a postnatal challenge infection. These results have important implications not only for epidemiological investigations, but also in designing government control programs for schistosomiasis.