ABSTRACT
OBJECTlVE To establish Tg(-6.3CYP3A65∶EGFP) transgenic zebrafish for quick, intuitive detection of heavy metals ( copper, cadmium and zinc) , dioxin-like PCBs ( PCB126) and other environmental pollutants. METHODS Tol2 transposon system was used to generate transgenic zebrafish lines Tg(-6.3CYP3A65∶EGFP) in which CYP3A65 promoter regualated labeled fluorescence. The effect of heavy mentals ( copper, cadmium and zinc ) and PCB126 on the relative amounts of CYP3A65 gene expression was determined by observing the change in fluorescence intensity. RESULTS The relative gene expression of CYP3A65 was significantly increased after 96 h exposure to copper 0.1 and 0.2μmol·L-1 , cadmium 0.35 and 0.7μmol·L-1 , zinc 1.5 and 3μmol·L-1 , and PCB126 2-32μmol·L-1 , respectively ( P<0.01) , but decreased after 96 h exposure to copper 0. 9 μmol·L-1 , cadmium 2. 7 and 5.4 μmol·L-1 , and zinc 24μmol·L-1 , respectively( P<0.01) . CYP3A65 gene expression was significantly increased after 168 h exposure to copper 0.1 and 0.2 μmol·L-1 , cadmium 0.35 and 0.7 μmol·L-1 , zinc 1.5 and 3 μmol·L-1, and PCB126 2-32 μmol·L-1, respectively(P<0.01), but decreased after 168 h exposure to copper 0.9 μmol·L-1, cadmium 2.7 and 5.4 μmol·L-1, and zinc 12 and 24 μmol·L-1( P<0.05) , in a concentration-dependent manner. CONCLUSlON The results suggest that zebrafish CYP3A65 gene expression and the CYP3A65 labeled fluorescence lines can be another candidate biomarker for detecting environmental pollutants.
ABSTRACT
OBJECTlVE To investigate the effect of α-glycan isolated from Isatis indigotica on humoral immunity and cellular immunity functions in mice immunized with H1N1 influenza vaccine. METHODS BALB/c mice were immunized intramuscularly once with H1N1 influenza vaccine ( 3 μg) plusα-glycan ( 100μg) each mouse. The serum total antibody titer and its isotype antibody titer of immu-nized mice were analyzed by ELlSA at 5, 8, 10, 12 and 14 d after injection at vaccine. The proliferation activities of spleen T and B lymphocytes were determined with MTT method. The levels of cytokines interferon-γ( lFN-γ) , tumor necrosis factorα( TNF-α) , interleukin-4( lL-4) and lL-12 were measured by ELlSA kits. The populations of CD4+, CD8+, CD3+ and CD19+ lymphocytes were determined by flow cytometry. Furthermore, the proliferation rate of macrophages was studied with MTT method in vitro. RESULTS The α-glycan from I.indigotica could gradually induce high specific-antibody production 5-14 d after immunization with H1N1 influenza antigen plus theα-glycan in mice compared to immunization with antigen alone ( P<0.01) . After injection of antigen withα-glycan for 5 d, the main lgG isotype was lgM, and the titer levels of total lgG, lgG1 , lgG2a and lgG2b were also significantly raised following 5-14 d after immunization. The α-glycan significantly promoted the spleen T and B lymphocytes proliferation ( growth rate 44.2%and 37.8%) , stimulated the secretion of lFN-γand lL-12 of splenocytes ( P<0.01, P<0.05) , and also promoted lL-4 secretion of thymocytes (P<0.01). The polysaccharide significantly raised the percent age of CD3+T cells ( P<0.01) , CD3+/CD19+ T lymphocytes ( P<0.01) , and CD8+ T cells ( P<0.01) but decreased the percentage of CD4+/CD8+ T lymphocytes compared with antigen alone group ( P<0.01) . Furthermore, the α-glycan exhibited significant effects on the proliferation and TNF-α secre-tion of MH-S macrophages. CONCLUSlON Theα-glycan isolated from I.indigotica can improve humoral and cellular immunity response in mice immunized with H1N1 influenza vaccine.