RESUMO
OBJECTIVE: This study aimed to evaluate the immunogenicity and protective efficacy of recombinant bacille calmette-guerin (rBCG) strains expressing Ag85A (A), CFP10 (C), ESAT6 (E), IL-12p70 (I), and fusion protein GM-CSF (G). METHOD: rBCGs were established by integrating of A, C, E, I, G, AE, CE, IE, GC, GE and GCE into Mycobacterium bovis BCG-1173 and BCG-SH. The macro-effects of rBCGs on mice were evaluated by phenotype and weight. The immunogenicity of rBCGs was analyzed by lgG, lgG1 and lgG2a antibody titers, and IFN-γ and IL-4 contents through Enzyme-linked immunosorbent assay (ELISA). Meanwhile, the proportions of CD4+ and CD8+ T splenic lymphocytes were determined using flow cytometry. The protective efficacy of rBCGs was evaluated by bacterial load in spleen and lung tissues from immunized mice. RESULTS: rBCGs exhibited no obvious side effects on mice. The antibody titers of lgG, lgG1 and lgG2a, proportion of CD4+ and CD8+ T cells, and concentrations of IFN-γ were found to be significantly higher in multiple-gene rBCGs than that in single-gene rBCGs (P < 0.05). Bacterial load in both spleen and lung tissues from mice infected with M. tuberculosis H37Rv were significantly reduced by rBCGs. A significantly lower bacterial load was revealed in rBCG-1173:A compared with multiple-gene rBCGs (P < 0.05). CONCLUSION: Immunogenicity was better on multiple-gene rBCGs than on single-gene rBCGs, while excellent protective efficacy was exhibited on rBCG-1173:A and BCG-1173.
Assuntos
Aciltransferases/imunologia , Antígenos de Bactérias/imunologia , Vacina BCG/imunologia , Proteínas de Bactérias/imunologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Interleucina-12/farmacologia , Tuberculose/prevenção & controle , Aciltransferases/genética , Animais , Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/genética , Vacina BCG/administração & dosagem , Vacina BCG/genética , Proteínas de Bactérias/genética , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Modelos Animais de Doenças , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Interferon gama/metabolismo , Interleucina-12/genética , Interleucina-4/metabolismo , Pulmão/microbiologia , Camundongos Endogâmicos BALB C , Mycobacterium bovis/genética , Mycobacterium bovis/imunologia , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/imunologia , Baço/microbiologia , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologiaRESUMO
Bacille Calmette-Guerin (BCG) is currently the only available vaccine against tuberculosis (TB), but its protective efficacy in adults is highly variable. This study aimed to compare the immune response induced by two widely used BCG strains: BCG China strain (derivative of BCG Danish strain) in DU2-III group and BCG Pasteur in DU2 -IV group. Healthy BALB/c mice were immunized with BCG China strain or BCG Pasteur strain. Specific IgG, IgG1, and IgG2a antibodies titers, the proliferation of splenocytes, the percentages of splenocyte subsets and the concentrations of induced IFN-γ and IL-4 at 6(th), 8(th), 10(th), and 12(th) weeks after the immunization were detected. We found that BCG Pasteur strain induced higher specific IgG and IgG1 titers, higher proliferation of splenocytes, higher percentages of CD4(+) or CD8(+) T cells, and higher concentration of secreted IFN-γ than BCG China strain. However, there were no significant differences in IgG2a titer and IL-4 concentration between both strains. In conclusion, our study shows that immune responses to BCG vaccine differ by strain, which may account for variable outcomes of BCG immunization.
RESUMO
OBJECTIVE: To investigate the association between KCNQ1 gene polymorphisms and type 2 diabetes (T2D) in an admixed ethnic minority, Uyghur population, living in the Northwest region of China. MATERIALS AND METHODS: We genotyped three tagging single-nucleotide polymorphisms rs2283171, rs11023485, and rs2283208 of the KCNQ1 gene in 1006 T2D participants and 1004 controls and conducted association analysis. RESULTS: The frequencies of the AG and GG genotypes and the G allele of rs2283171 were higher in the control group (51.4%, 22%, and 47.7%, respectively) than in the case group (49%, 17.6%, and 42.1%, respectively). The minor G allele decreased the risk of T2D with a per-allele odds ratio of 0.79 (95% CI: 0.70-0.90) for the additive genetic model in univariate analysis (p = 0.0001). After adjustment for the covariates of age, gender, smoking, alcohol use, systolic blood pressure (SBP), diastolic blood pressure (DBP), body mass index (BMI), triglyceride (TG), and total cholesterol (TC), the diabetic protective effect of the rs2283171-G allele remained. No difference was observed in the frequency distributions of the rs11023485 and rs2283208 genotypes between the two groups. CONCLUSION: We identified a novel association between rs2283171 of KCNQ1 and T2D in the Uyghur population. Further association and functional studies are required to identify the causal functional variant that is in linkage disequilibrium with this polymorphism.