Aim To study the effects on T lymphocyte subsets in spleen of mice immunized with recombinant BCGSj26GST. Methods Inthe first experiment, BALB/c mice were immrnized subcutaneously by 106 and 108 CFU BCG-Sj26GST respectively. ALLthe mice were artifically challenged with cerariae of Schistosoma japonicum on 8weeks after immunization, six after challenge, the mice were killed, and the spleens were removed, cells were prepared seperately and were analysed by immunofluorescence with conjugated monoclonal antibodies in a FACsort cytofiuorimeter at 523 nm, PBS treated mice were serwed as control. In the second experiment, after immunized subcutanenously or inntraveously by 106 CFU vaccine, 4 mice were ranndonly killed to separate spleens on 0wk, 4wk, 8wk, 10wk, 14wk and 16wk after immurization, the percentage of CD+4 and CDs+ subsets was analysed as above. Results In the first experiment, CD+4 subsets increased renarkably, but CD+8 subsetsdid slightly by immunization with the vaccine against challenge with S.j. Cercariae, in the second experiment, the dynamic observation showed that in the subcutaneous and intravenous group, CD+4 subsets increased obviously since 10wk and 8wk respectively, CD8+ subsets hadno obvious changeover 16 weeks of observation , in the subcutaneous groupbuttheCD8+ subsets rose lightly on 4-16wk in the intravenous group. Conclusion On the basis of this study it's suspected that CD+4 subsets might play an important role in the protective immunity induced by the vaccine

Aim Protective immunity of DNA vaccine pCDSj32 for Schistosoma japonica by different injection times and challenge time after the last inoculation in mice was investigated. Methods 100μg/100μl DNA vaccine pCDSj32 was injected into the quadriceps muscles of the BALB/c mice. The mice were divided into once immunized groups and three times immunized groups. Challenge infection was applied 4wk or 8wk after the last inoculation with 40 cercariae each mouse. The adult reduction rates and the EPG in the livers of mice were detected 6wk after challenge. Results Substantially protective immunity was obtained when compared the immunized groups with the control. The adult reduction rates were 35.61～44.44 ％ ,and the egg reduction rates in the livers were 39. 64～69.06％. Conclusion The protective immunity could be influenced by different times of DNA vaccine inoculation and the challenge time after the last immunization. The best protective results could be obtained with inoculation once combined with the challenge 8wk after the immunization of DNA vaccine.

Objective To study the expression of bivalent DNA vaccine against Schistosoma japonicum in vitro/vivo and lasting time in vivo. Methods The bivalent DNA pVIVO2-SjFABP/Sj23 was transfected transiently into the human embryonic kidney cells of the line 293. RT-PCR was used to detect the expressions of SjFABP and Sj23 mRNA in the 293 cells. Indirect immunofluorescence antibody test(IFAT) was used to detect the expressions of SjFABP and Sj23 proteins. Twelve BALB/c mice were inoculated with pVIVO2-SjFABP/Sj23 via intramuscular injection. Two blood samples were collected from eye sockets and two mice were vivi-perfused each month. This work lasted for 6 months. IFAT was used to detect the expression of proteins in skeletal muscle. Western-blot was used to detect the serum IgG level. Results RT-PCR and IFAT showed the expressions of SjFABP and Sj23 in the HEK-293 cells. IFAT showed SjFABP/ Sj23 was present in vivo at least for 6 months. Special IgG was not detected by Western blot. Conclusions pVIVO2-SjFABP/Sj23, bivalent DNA vaccine, could express correctly in vitro/vivo, and lasts for 6 months at least in vivo.

Objective To construct a multivalent DNA vaccine.\ Methods\ The multivalent DNA vaccine candidates pBK Sj26 Sj23,pBK Sj32 Sj23 were constructed based on the plasmids pBluescript Sj26,pBluescript Sj32 and pBluescript Sj23 with three pairs of specific primers using DNA recombinant technique. In the primers, a synthetic linker sequence encoding a peptide was designed,and the antigen genes Sj26 and Sj23,Sj32 and Sj23 were then ligated. After identification, the quadriceps muscle of mice were immunized with the multivalent antigen genes. Four weeks after immunization, the multivalent antigen genes were present in the muscular tissue of mice by PCR.\ Results\ The eukaryotic plasmids including multivalent antigens of S.japonicum were constructed successfully, and the plasmids including multivalent antigen gene could be stably existing in the muscle tissue of mice and the multivalent antigens could be expressed in the muscle tissue cells of mice.\ Conclusion\ A multivalent S.japonicum DNA vaccine has been established.

Objective To observe the dynamic change of immune response in mice infected with Echinococcus alveolaris(AE) at difference period of time, and to explore hostalveo’s immune regulation. Methods The infection lasted and was followed up for 25 weeks. The spleen cells from BALB/c mice infected with AE stimulated with EmAg and ConA or PHA in vitro . IL-2R, IFN-?, TNF-?, IL-1 and specific IgG subclasses were determined by ELISA. NO was tested by chemical assay. Results NO level sharply rised in 16 weeks after BALB/c mice were infected with AE. The levels of IgG1 and IgG3 significantly increased 8 weeks after infection, and remained elevating throughout the period of observation. IgG3 showed slight increase, IgG2a and IgG2b appeared low level following infection. The production of IL-2R and TNF? increased significantly 8 weeks of infection, while IL-2R sharply decreased in 12 weeks of infection. During the period of 2-12 weeks of infection there was an increase in IL-1 secreting. The level of IL-1 and TNF? rapidly increased since 16 weeks post infection. High level of IFN-? was detected during the period of observation, and showed a peak at 12 weeks. Conclusion Th1 is the major response in the early stage of infection,which is replaced by Th2 response in later period of infection.

Immuno-blot was used in diagnosis of schistosomiasis japonica using diagnostic 31/32 KD proteins in S.japonicum Among 52 confirmed schistosemiasis cases 100% showed positive reaction while none of the sera of 20 normal control reacted. No cross reactions occured with sera from 36 paragonimiasis; 26 cysticercosis and 50 trichinelliasis cases. However, 11.5-58.3%cross reactions were found with above sera in IHA and ELISA. The diagnostic value of immuno-blot and 31/32 kD schistosome proteins were confirmed.A field application of immuno-blot in diagnosis of schistosomiasis japonica was performed. The positive rates in immuno-blot and IHA were 58.1% and 54.4% respectively in 136 cohorts with and without past history of schistosomiasis in the endemic area. It was found that immuno-blot was highly sensitive, specific and reproducible.It was easy to perform and suitable for field use.

Objective To explore the feasibility of establishing animal model of schistosomiasis through subcutaneous injection of IMDM liquid and intramuscular injection of IMDM liquid both of which contained the cercariae.Methods The mice were infected with schistosome cercariae by three different ways: subcutaneous injection(Group A),intramuscular infection(Group B) and the classical method: skin infection(Group C).Forty-five days post-infection, the mice were sacrified and the adult schistosomes were investigated. The serum IgG antibodies were detected by indirect ELISA in 15 and 45 days after infection. Results The recovery adult worm rates were 39.2% in Group A,32.3% in Group B and 72.8% in Group C,and there was a significant difference among them (P

Objective To evaluate the mutagenicity of Schistosoma japonicum bivalent DNA vaccine.Methods The mutagenicity of Schistosoma japonicum bivalent DNA vaccine was studied by Ames test,micronucleus test and chromosome aberration test.Results On the conditions of actived and unactived,Schistosoma japonicum bivalent DNA vaccine did not lead obvious increase of colony units,and the result of the Ames test was negative.Compared with the control group,there were no significant differences in the treated groups on the frequency of micronucleus in PCE or chromosome aberration.Conclusion There is no mutagenicity of Schistosoma japonicum bivalent DNA vaccine.

Objective To study the immune protection of Schistosoma japonicum fatty acid binding protein (Sj14FABP) DNA vaccine enhanced by IL-12. Methods The recombinant plasmids pVIVO2-Sj14FABP and pVIVO2-IL12-Sj14FABP were constructed respectively, and were prepared on a large scale after identification. 48 male BALB/c mice were divided into 4 groups randomly. In group A, B, C, and D, each mouse was injected intramuscularly with 100 ?l 0.9% NaCl, 100?g pVIVO2, 100?g pVIVO2-Sj14FABP and 100 ?g pVIVO2-IL12-Sj14FABP respectively. 30 days after immunization each mouse was challenged with 40?2 cercariae of S. japonicum. On day 45 after challenge, all mice were sacrificed to count the number of recovered adult worms and the hepatic eggs. Sera from mice were used to detect IgG antibody. The production of IL-2, IL-4 and IFN-? in the supernatant of spleen cells was observed by means of sandwich ABC-ELISA. Results The recombinant plasmids pVIVO2-Sj14FABP and pVIVO2-IL12-Sj14FABP were constructed. The worm reduction rate in group C and D was 24.11% and 39.4%, as well as liver egg reduction rate of 27.2% and 32.8% respectively. The level of IL-2 and IFN-? in group D increased significantly, while IL-4 secretion decreased(P0.05). Conclusion Sj14FABP DNA vaccine induces partial protective immunity in BALB/c mice. IL-12 drives the immune response toward a Th1 direction, and enhances the protective immune effect of the vaccine. [

OBJECTIVETo investigate the association between histocompatibility leukocyte antigen (HLA)-DRB1 alleles and alveolar echinococcosis (AE).

METHODSThirty-five patients with AE in high prevalence areas in Gansu Province of China were tested for the HLA-DRB1 gene using the polymerase chain reaction with sequence-specific primer (PCR-SSP) technique. The results were compared with those of 104 healthy individuals.

RESULTSThe frequency of the HLA-DRB1 * 040x gene was 26% in the patient group, which was significantly higher than that in the control group (9.62%) with a relative risk (RR) of 4.45 (chi(2) = 13.67, P < 0.01), and an etiological fraction (EF) of 0.20. The frequency of the HLA-DRB1 * 0701 allele was significantly lower in the patient group (2.86%) as compared to the control group (13.94%; chi(2) = 6.67, P < 0.05) with a preventable fraction (PF) of 0.30. The frequencies of other DRB1 alleles were not significantly different.

CONCLUSIONSusceptibility to AE is significantly associated with the HLA-DRB1 * 040x. HLA-DRB1 * 0701 gene might confer protection against AE in humans.

Adolescent ; Adult ; Aged ; Alleles ; Child ; China ; epidemiology ; Echinococcosis, Hepatic ; epidemiology ; genetics ; Female ; HLA-DR Antigens ; genetics ; HLA-DRB1 Chains ; Humans ; Male ; Middle Aged ; Prevalence