The imbalance between β-amyloid (Aβ) generation and clearance plays a fundamental role in the pathogenesis of Alzheimer's disease (AD). The sporadic form of AD is characterized by an overall impairment in Aβ c...The imbalance between β-amyloid (Aβ) generation and clearance plays a fundamental role in the pathogenesis of Alzheimer's disease (AD). The sporadic form of AD is characterized by an overall impairment in Aβ clearance. Immunotherapy targeting Aβ clearance is believed to be a promising approach and is under active clinical investigation. Autophagy is a conserved pathway for degrading abnormal protein aggregates and is crucial for Aβ clearance. We previously reported that oral vaccination with a recombinant AAV/Aβ vaccine increased the clearance of Aβ from the brain and improved cognitive ability in AD animal models, while the underlying mechanisms were not well understood. In this study, we first demonstrated that oral vaccination with rAAV/Aβ decreased the p62 level and up-regulated the LC3B- II/LC3B-I ratio in APP/PS1 mouse brain, suggesting enhanced autophagy. Further, inhibition of the Akt/mTOR pathway may account for autophagy enhancement. We also found increased anti-Aβ antibodies in the sera of APP/PS1 mice with oral vaccination, accompanied by elevation of complement factors C1q and C3 levels in the brain. Our results indicate that autophagy is closely involved in oral vaccination-induced Aβ clearance, and modulating the autophagy pathway may be an important strategy for AD prevention and intervention.展开更多
为研制一种能有效控制猪圆环病毒2型(porcine circovirus type 2,PCV2)的新型疫苗,本试验将PCV2的ORF2基因克隆至植物乳杆菌表达载体pSCPSP超强启动子SCP的下游,构建重组表达质粒pSCPSP-Cap,用电击转化法转化克隆至表达宿主菌植物乳杆菌...为研制一种能有效控制猪圆环病毒2型(porcine circovirus type 2,PCV2)的新型疫苗,本试验将PCV2的ORF2基因克隆至植物乳杆菌表达载体pSCPSP超强启动子SCP的下游,构建重组表达质粒pSCPSP-Cap,用电击转化法转化克隆至表达宿主菌植物乳杆菌,获得一株重组植物乳杆菌。以SDS-PAGE和Western blotting法检测24h上清液中表达的蛋白;将8周龄的SPF级BALB/c小鼠随机分组,每组8只,分别设置对照组、空载体组、灌胃组、饮水组、灭活疫苗组,试验14、28、42和56d后对小鼠采血,分离血清,利用PCV2ELISA抗体检测试剂盒检测小鼠血清中PCV2的抗体水平。SDS-PAGE、Western blotting结果显示,PCV2衣壳蛋白在植物乳杆菌中成功分泌表达,表达的蛋白分子质量为28ku,且具有良好的反应原性,重组植物乳杆菌免疫小鼠诱导机体产生PCV2特异性抗体显著高于其他组(P<0.05)。结果表明,PCV2的ORF2基因在植物乳杆菌中成功表达,且具有良好的生物活性,可为PCV2口服疫苗的开发研究提供理论参考。展开更多
AIM: To construct the recombinant Lactococcus/actis as oral delivery vaccination against malaria. METHODS: The C-terminal 19-ku fragments of MSP1 (MSP-119) of Plasmodium yoelii265-BY was expressed in L. lactis and...AIM: To construct the recombinant Lactococcus/actis as oral delivery vaccination against malaria. METHODS: The C-terminal 19-ku fragments of MSP1 (MSP-119) of Plasmodium yoelii265-BY was expressed in L. lactis and the recombinant L. lact/s was administered orally to BALB/c and C57BL/6 mice. After seven interval vaccinations within 4 wk, the mice were challenged with P. yoelii 265-BY parasites of erythroo/tic stage. The protective efficacy of recombinant L. lactiswas evaluated. RESULTS: The peak parasitemias in average for the experiment groups of BALB/c and C57BL/6 mice were 0.8± 0.4% and 20.8±26.5%, respectively, and those of their control groups were 12.0±0.8% and 60.8±9.6%, respectively. None of the BALB/c mice in both experimental group and control group died during the experiment. However, all the C57BL/6 mice in the control group died within 23 d and all the vaccinated mice survived well. CONCLUSION: The results imply the potential of recombinant L. lactis as oral delivery vaccination against malaria.展开更多
基金supported by the National Basic Research Development Program of China(2012CB911000 and 2012CB911004)the NSFC-JSPS Cooperation Program (81211140047)the National Natural Science Foundation of China(81171015)
文摘The imbalance between β-amyloid (Aβ) generation and clearance plays a fundamental role in the pathogenesis of Alzheimer's disease (AD). The sporadic form of AD is characterized by an overall impairment in Aβ clearance. Immunotherapy targeting Aβ clearance is believed to be a promising approach and is under active clinical investigation. Autophagy is a conserved pathway for degrading abnormal protein aggregates and is crucial for Aβ clearance. We previously reported that oral vaccination with a recombinant AAV/Aβ vaccine increased the clearance of Aβ from the brain and improved cognitive ability in AD animal models, while the underlying mechanisms were not well understood. In this study, we first demonstrated that oral vaccination with rAAV/Aβ decreased the p62 level and up-regulated the LC3B- II/LC3B-I ratio in APP/PS1 mouse brain, suggesting enhanced autophagy. Further, inhibition of the Akt/mTOR pathway may account for autophagy enhancement. We also found increased anti-Aβ antibodies in the sera of APP/PS1 mice with oral vaccination, accompanied by elevation of complement factors C1q and C3 levels in the brain. Our results indicate that autophagy is closely involved in oral vaccination-induced Aβ clearance, and modulating the autophagy pathway may be an important strategy for AD prevention and intervention.
基金Supported by the UNDP/World Bank/WHO Special Programme for Research and Training in Tropical Diseases (TDR), No.980198
文摘AIM: To construct the recombinant Lactococcus/actis as oral delivery vaccination against malaria. METHODS: The C-terminal 19-ku fragments of MSP1 (MSP-119) of Plasmodium yoelii265-BY was expressed in L. lactis and the recombinant L. lact/s was administered orally to BALB/c and C57BL/6 mice. After seven interval vaccinations within 4 wk, the mice were challenged with P. yoelii 265-BY parasites of erythroo/tic stage. The protective efficacy of recombinant L. lactiswas evaluated. RESULTS: The peak parasitemias in average for the experiment groups of BALB/c and C57BL/6 mice were 0.8± 0.4% and 20.8±26.5%, respectively, and those of their control groups were 12.0±0.8% and 60.8±9.6%, respectively. None of the BALB/c mice in both experimental group and control group died during the experiment. However, all the C57BL/6 mice in the control group died within 23 d and all the vaccinated mice survived well. CONCLUSION: The results imply the potential of recombinant L. lactis as oral delivery vaccination against malaria.