Time filter

Source Type

Xie S.Y.,Jiangxi Provincial Institute of Parasitic Diseases
Zhongguo ji sheng chong xue yu ji sheng chong bing za zhi = Chinese journal of parasitology & parasitic diseases | Year: 2010

To synthesize and express the gene of egg protein IPSE (IL-4-inducing principle of Schistosoma mansoni eggs) and evaluate its immunologic characteristics. The IPSE gene of S. mansoni was synthesized by overlapping PCR, and confirmed by DNA sequencing, The recombinant plasmid IPSE-pET32a(+) was constructed by inserting the gene of IPSE into expression vector pET32a(+) at the downstream of thioredoxin (Trx) coding sequence. The recombinant plasmid IPSE-pET32a(+) was transformed into E. coli BL21(DE3) and followed by expression of the protein induced by IPTG. Large-scale fusion protein was prepared and purified with Ni affinity chromatography gel under denaturing conditions. A small amount of soluble Trx-IPSE was obtained by dialyzing the fusion protein in a large volume of PBS. Western blotting was used to detect if the recombinant IPSE was recognized by the IgG antibody in the pooled patient sera of schistosomiasis japonica and its binding capacity to the non-specific IgE antibody in the sera of healthy persons. DNA sequencing confirmed that the nucleotide sequence of synthesized IPSE gene was completely identical to the native one. SDS-PAGE showed that the recombinant plasmid IPSE/pET32a(+) expressed a fusion protein with an Mr 35700 after being induced by IPTG. The pure fusion protein Trx-IPSE reacted positively with the pooled sera of schistosomiasis patients under either denaturing or renaturing conditions. The protein Trx-IPSE also reacted with the nonspecific IgE in the sera of healthy persons. The IPSE gene of Schistosoma mansoni has been synthesized, and the recombinant can react with natural antibody IgG against S. japonicum and non-specifically bind to IgE antibody. Source

Alberts C.J.,Rotterdam University | Smith W.C.S.,University of Aberdeen | Meima A.,Municipal Public Health Service Rotterdam Rijnmond | Wang L.,Jiangxi Provincial Institute of Parasitic Diseases | Richardus J.H.,Rotterdam University
Bulletin of the World Health Organization | Year: 2011

Objective To assess different countries' chances of attaining the 2011-2015 global leprosy target set by the World Health Organization (WHO) and to assess the strategy's effect on the prevalence of grade 2 disability (G2D). Methods Trends in G2D rate were analysed for Brazil, China, India and Thailand and figures were compared with the WHO target: a 35% decrease by 2015 relative to the 2010 baseline. To estimate the prevalence of G2D in 2015 and 2035 for each country three assumptions were made: (i) maintenance of the current trend; (ii) attainment of the WHO target, and (iii) reduction of G2D by 50% every 5 years relative to 2010. Findings Since 1995, the G2D rate has decreased every 5 years in Brazil, China, India and Thailand by 12.7% (95% confidence interval, CI: 6.6-18.3), 7.7% (95% CI: 1.1-12.8), 53.7% (95% CI: 38.1-65.4) and 35.9% (95% CI: 23.4-46.3), respectively. New cases with G2D detected after 2010 will contribute 15% (Brazil), 3% (China), 2.5% (India) and 4% (Thailand) to the total prevalence of G2D in 2015. If no policies are changed, between 2015 and 2035, the prevalence of G2D will decrease by more than half in China, India and Thailand, and by 16% in Brazil. Conclusion The implications of attaining the WHO target are different for each country and using indicators other than G2D prevalence will help monitor progress. The strategy will not immediately reduce the prevalence of G2D, but if it is applied consistently over the next 25 years, its long-term effect can be substantial. Source

Tian F.,Nanjing Medical University | Tian F.,Yangzhou University | Lin D.,Nanjing Medical University | Lin D.,Jiangxi Provincial Institute of Parasitic Diseases | And 8 more authors.
PLoS ONE | Year: 2010

Background: The vaccination of radiation-attenuated Schistosoma japonicum cercariae can induce effective protection in artiodactyl, but the immune events related to protective immunity are not fully understood. To provide a paradigm for a human recombinant antigen vaccine, we have undertaken a vaccination and challenge experiment in pigs, which was recognized as an appropriate animal model in this type of study because of their similarity to human in immunology, and investigated the relative immune events induced by the radiation-attenuated S. japonicum cercariae. Methods and Findings: We found that pigs immunized once with 400 mw UV-irradiated cercariae exhibited 63.84% and 71.82% reductions in worm burden and hepatic eggs respectively. Protective immunity in vaccinated pigs was associated with high level productions of IgM, total IgG, IgG1 and IgG2; IgG2 was significantly increased in the acute infection. IFN-γ levels could be elicited by immunization. At week 6 post-infection, IFN-γ, IL-4 and IL-10 levels also showed a dramatic rise synchronously in vaccinated pigs. Moreover, the granzyme b, nk-lysin, ifnc, il4 and il10 mRNA levels in early skin-draining lymph nodes of immunized pigs were higher than those in pigs with non-irradiated cercariae infection. In addition, cytotoxicity-related genes in the mesenteric lymph nodes were significantly upregulated in vaccinated pigs in the acute infection. Conclusion/Significance: Our results demonstrated that IFN-γ and IgG2 antibody production, as well as genes related to cytotoxicity are associated with the high level protection induced by UV-irradiated Schistosoma japonicum vaccine. These findings indicated that optimal vaccination against S. japonicum required the induction of IFN-γ, IgG2 antibody related to Th1 responses and cytotoxicity effect. © 2010 Tian et al. Source

Yu L.-L.,Zhejiang Academy of Medical science | Ding J.-Z.,Zhejiang Academy of Medical science | Wen L.-Y.,Zhejiang Academy of Medical science | Lou D.,Zhejiang Academy of Medical science | And 5 more authors.
Parasites and Vectors | Year: 2011

Background: Schistosomiasis japonica (schistosomiasis) is a zoonosis that can seriously affect human health. At present, the immunodiagnostic assays for schistosomiasis detection are time-consuming and require well-trained personnel and special instruments, which can limit their use in the field. Thus, there is a pressing need for a simple and rapid immunoassay to screen patients on a large scale. In this study, we developed a novel rapid dipstick with latex immunochromatographic assay (DLIA) to detect anti-Schisaosoma japonicum antibodies in human serum. Results: Using latex microspheres as a color probe, DLIA was established to test standard positive and negative sera, in comparison with the classical enzyme-linked immunosorbent assay (ELISA). The sensitivity and specificity of DLIA were 95.10% (97/102) and 94.91% (261/275), respectively. The cross-reaction rates with clonorchiosis, intestinal nematodes, Angiostrongylus cantonensis and paragonimiasis were 0, 0, 0 and 42.11% respectively. All the results showed no significant difference to the ELISA. In field tests, 333 human serum samples from an endemic area were tested with DLIA, and compared with ELISA and Kato-Katz method. There was no significant difference between DLIA and ELISA on positive and negative rates of detection; however, significant differences existed between DLIA and Kato-Katz method, and between ELISA and Kato-Katz method. The kappa value between DLIA and ELISA was 0.90. Conclusions: This is the first study in which DLIA was used to detect anti-Schistosoma japonicum antibody. The results show that DLIA is a simple, rapid, convenient, sensitive and specific assay for the diagnosis of schistosomiasis and is therefore very suitable for large-scale field applications and clinical detection. © 2011 Yu et al; licensee BioMed Central Ltd. Source

Xie S.-Y.,Jiangxi Provincial Institute of Parasitic Diseases | Yuan M.,Jiangxi Provincial Institute of Parasitic Diseases | Ji M.-J.,Nanjing Medical University | Hu F.,Jiangxi Provincial Institute of Parasitic Diseases | And 6 more authors.
Parasites and Vectors | Year: 2014

Background: In recent field surveys, we failed to detect the presence of specific antibody against Schistosoma japonicum in some egg-positive patients by commonly used immunodiagnostic kits. To find out whether low levels of specific antibody truly exist among egg-positive individuals and elucidate the underlying immune mechanisms, we carried out a cross-sectional epidemiologic study in a S. japonicum low transmission endemic area of Poyang Lake region, China and compared the humoral and cellular immune characteristics between S. japonicum high and low antibody responders. Methods. Kato-Katz thick smear assay was used to determine the schistosomiasis status of 3,384 participants residing in two Poyang Lake region villages, Jiangxi, China. Among the 142 stool egg-positive participants, we identified low and high S. japonicum antibody responders with soluble egg antigen (SEA) and adult worm antigen (AWA) specific IgG levels by adopting ROC curve analysis. To compare the humoral and cellular immune responses between high and low S. japonicum antibody responders, serum specific antibody levels as well as the percentage of T lymphocyte subpopulation in PMBC, and cell stimulated cytokines (IFN- gamma and interlukin-10) were detected. Results: Eight S. japonicum egg-positive participants were defined as low antibody responders. Although the percentage of CD3+T cells in low responders was slightly higher and the percentage of CD4+ T cells, CD8+ T cells, the ratio of CD4+/CD8+ and CD4+ CD25+ Treg cells were lower than those in high responders, the differences between the two groups were not significant (P > 0.05). AWA -stimulated interlukin-10 level was significantly higher in high responders, while other cytokines did not show differences between two groups. For antibody profiles, except AWA specific IgA, significant differences of each antibody isotype between low and high responders were detected (P < 0.05). Conclusions: Our study confirmed that there are S. japonicum antibody low responders among schistosome egg-positive residents in S. japonicum low-transmission areas in China. Thus, mis-diagnosis using immune-diagnosis kits do exist. Significant differences of responding antibody levels between low and high responders were detected, while no major cellular response changes were observed. © 2014 Xie et al.; Licensee BioMed Central Ltd. Source

Discover hidden collaborations