目的研究重组毕赤酵母表达的乙型肝炎病毒preS2S蛋白的纯化方法及免疫效果。方法甲醇诱导含preS2S基因的重组毕赤酵母菌,采用蔗糖区带速率离心、Butyl-S-Sepharose 4FF疏水层析和DEAE-Sepharose Fast Flow离子交换层析等方法,对表达产...目的研究重组毕赤酵母表达的乙型肝炎病毒preS2S蛋白的纯化方法及免疫效果。方法甲醇诱导含preS2S基因的重组毕赤酵母菌,采用蔗糖区带速率离心、Butyl-S-Sepharose 4FF疏水层析和DEAE-Sepharose Fast Flow离子交换层析等方法,对表达产物进行纯化。纯化后蛋白经SDS-PAGE和Western blot方法鉴定,制备成疫苗,并进行效力试验。放射免疫法检测免疫小鼠血清抗体浓度,计算ED50和相对效力。ELISA法检测血清中的preS2S抗体。结果纯化后的preS2(epi)S蛋白相对分子质量约为27000,且能与特异性抗体结合。两批纯化蛋白制备的疫苗ED50分别为0.35和0.48μg/ml,参比苗为0.52μg/ml。2批疫苗的体外相对效力分别为1.5和1.1,均合格,血清抗体平均浓度为808和784mIU/ml,参比苗为312mIU/ml。2批疫苗免疫小鼠后均产生了preS2抗体。结论该纯化方法实用有效,纯化后的preS2(epi)S蛋白比S蛋白具有更好的免疫原性。展开更多
Despite the long availability of a traditional prophylactic vaccine containing the HBV surface antigen(HBsA g) and aluminum adjuvant, nearly 10% of the population remains unable to generate an effective immune respons...Despite the long availability of a traditional prophylactic vaccine containing the HBV surface antigen(HBsA g) and aluminum adjuvant, nearly 10% of the population remains unable to generate an effective immune response. Previous studies have indicated that hepatitis B virus(HBV) PreS 2-S is abundant in T/B cell epitopes, which induces a stronger immune response than HBsA g, particularly in terms of cytotoxic T lymphocyte(CTL) reaction. In the current study, the HBV PreS 2-S gene encoding an extra26 amino acids(PreS 2 C-terminus) located at the N-terminus of HBsA g was cloned into the pV CH1300 expression vector. Pre S2-S expressed in the methylotrophic yeast, Hansenula polymorpha, was produced at a yield of up to 250 mg/L. Subsequent purification steps involved hydrophobic adsorption to colloidal silica, ion-exchange chromatography and density ultracentrifugation. The final product was obtained with a total yield of ~15% and purity of ~99%. In keeping with previous studies, ~22 nm viruslike particles were detected using electron microscopy. The generated PreS 2-S antigen will be further studied for efficacy and safty in animals.展开更多
Objective:To investigate the relationship between variation of HBV preS genes and clinical consequencesof HBV infection. Methods: We selected 3 groups (3 in each) of HBV infected individuals including those of acutein...Objective:To investigate the relationship between variation of HBV preS genes and clinical consequencesof HBV infection. Methods: We selected 3 groups (3 in each) of HBV infected individuals including those of acuteinfection with complete recovery, chronic HBV carriers and chronic severe hepatitis B. The preS genes were amplified from serum samples with half nested PCR. The PCR products were cloned into M13 vectors and 10 cloneswere randomly selected for each individual and sequenced with standard methods. A total of 90 clones were sequenced and analyzed by DNA homological comparison. Results: The characteristics of the preS genes were significantly different in HBV-infected individuals with different clinical consequences.①As for acute hepatitis B, thepreS function domains were stable and no changes in epitopes for T and B cells were found. ②For chronic HBVcarriers, the function domains within preS proteins showed potentially changes with epitope drifts of T and B cellsbecause of the high variation of HBV preS genes. ③For chronic severe hepatitis B, there were special changes inthe function domains of B cells. The abnormally high immune response would cause severe liver injury in these individuals. Conclusion: This study provides experimental evidence for researches about the possible association ofvariation of preS1/S2 functional regions with clinical consequences.展开更多
目的探讨包含前S1、前S2和S抗原的新型重组乙型肝炎疫苗(简称SS1S2疫苗)在小鼠中诱导体液和细胞免疫应答的能力以及在无应答小鼠中的免疫原性。方法以不同剂量(2.0、0.5、0.125、0.03μg)的SS1S2疫苗或商品化单S乙型肝炎疫苗(简称S疫苗...目的探讨包含前S1、前S2和S抗原的新型重组乙型肝炎疫苗(简称SS1S2疫苗)在小鼠中诱导体液和细胞免疫应答的能力以及在无应答小鼠中的免疫原性。方法以不同剂量(2.0、0.5、0.125、0.03μg)的SS1S2疫苗或商品化单S乙型肝炎疫苗(简称S疫苗)免疫BALB/c小鼠,于免后1、2、4周时采血,采用ELISA法检测两组疫苗单只小鼠血清的S、前S1和前S2抗体。以SS1S2疫苗或单S疫苗于0和3周时免疫BALB/c小鼠,每只5μg,于每次免疫后1周处死一半小鼠,制备脾脏淋巴细胞,采用ELISPOT法检测分泌IFNγ的细胞毒T淋巴细胞(cytotoxic T lymphocyte,CTL)频数。以单S疫苗于0、2、4周时免疫NIH小鼠,于末次免疫后4周采血,测定S抗体,筛选无应答小鼠。将无应答小鼠分为两组,分别用SS1S2疫苗或单S疫苗加强免疫1次,于免后1个月采血,测定S抗体。结果免后1、2周,2.0、0.5、0.125μg的SS1S2疫苗组S抗体阳转率均高于同剂量的单S疫苗组,且能诱导前S1、前S2抗体产生,而单S疫苗组无前S1、前S2抗体产生;免后4周,两组疫苗的抗体阳转率在总体上继续增加,2.0、0.5、0.125μg的SS1S2疫苗组S抗体几何平均滴度(GMT)均高于同剂量的单S疫苗组,且有一定滴度的前S1、前S2抗体,而单S疫苗组无前S1、前S2抗体产生。初免后1、4周,SS1S2疫苗组小鼠IFNγ分泌细胞频数均明显高于单S疫苗组(P<0.05或<0.01)。以0.5μg SS1S2疫苗或单S疫苗对经3剂单S疫苗免疫无应答NIH小鼠进行1次加强免疫后,SS1S2疫苗组小鼠抗体阳转率和GMT均明显高于单S疫苗组(P均<0.01)。结论与商品化单S乙肝疫苗相比,SS1S2疫苗在小鼠中诱导的抗体产生时间较早,抗体阳转率和抗体滴度较高,还能诱导前S1、前S2抗体产生;SS1S2疫苗比单S疫苗诱导了更高水平的特异性CTL应答;在无应答小鼠中能诱导更大比例和更高滴度的保护性抗体产生,表现出更好的免疫原性。展开更多
乙型肝炎病毒(Hepatitis B Virus,HBV)外膜蛋白含PreS1、PreS2和S 3种蛋白,位于病毒颗粒的外表面,参与病毒颗粒的吸附、组装与成熟,在保护性免疫应答反应中起重要作用,HBV感染肝细胞所合成的外膜蛋白对肝细胞的生长、代谢,甚至是恶性转...乙型肝炎病毒(Hepatitis B Virus,HBV)外膜蛋白含PreS1、PreS2和S 3种蛋白,位于病毒颗粒的外表面,参与病毒颗粒的吸附、组装与成熟,在保护性免疫应答反应中起重要作用,HBV感染肝细胞所合成的外膜蛋白对肝细胞的生长、代谢,甚至是恶性转化产生一系列重要的生物学调节效应,外膜蛋白的变异使得HBV对受染肝细胞的影响非常复杂且成多样化,在病毒性乙型肝炎慢性化及其相关疾病演变过程的分子病理机制扮演重要角色。展开更多
文摘目的研究重组毕赤酵母表达的乙型肝炎病毒preS2S蛋白的纯化方法及免疫效果。方法甲醇诱导含preS2S基因的重组毕赤酵母菌,采用蔗糖区带速率离心、Butyl-S-Sepharose 4FF疏水层析和DEAE-Sepharose Fast Flow离子交换层析等方法,对表达产物进行纯化。纯化后蛋白经SDS-PAGE和Western blot方法鉴定,制备成疫苗,并进行效力试验。放射免疫法检测免疫小鼠血清抗体浓度,计算ED50和相对效力。ELISA法检测血清中的preS2S抗体。结果纯化后的preS2(epi)S蛋白相对分子质量约为27000,且能与特异性抗体结合。两批纯化蛋白制备的疫苗ED50分别为0.35和0.48μg/ml,参比苗为0.52μg/ml。2批疫苗的体外相对效力分别为1.5和1.1,均合格,血清抗体平均浓度为808和784mIU/ml,参比苗为312mIU/ml。2批疫苗免疫小鼠后均产生了preS2抗体。结论该纯化方法实用有效,纯化后的preS2(epi)S蛋白比S蛋白具有更好的免疫原性。
文摘Despite the long availability of a traditional prophylactic vaccine containing the HBV surface antigen(HBsA g) and aluminum adjuvant, nearly 10% of the population remains unable to generate an effective immune response. Previous studies have indicated that hepatitis B virus(HBV) PreS 2-S is abundant in T/B cell epitopes, which induces a stronger immune response than HBsA g, particularly in terms of cytotoxic T lymphocyte(CTL) reaction. In the current study, the HBV PreS 2-S gene encoding an extra26 amino acids(PreS 2 C-terminus) located at the N-terminus of HBsA g was cloned into the pV CH1300 expression vector. Pre S2-S expressed in the methylotrophic yeast, Hansenula polymorpha, was produced at a yield of up to 250 mg/L. Subsequent purification steps involved hydrophobic adsorption to colloidal silica, ion-exchange chromatography and density ultracentrifugation. The final product was obtained with a total yield of ~15% and purity of ~99%. In keeping with previous studies, ~22 nm viruslike particles were detected using electron microscopy. The generated PreS 2-S antigen will be further studied for efficacy and safty in animals.
文摘Objective:To investigate the relationship between variation of HBV preS genes and clinical consequencesof HBV infection. Methods: We selected 3 groups (3 in each) of HBV infected individuals including those of acuteinfection with complete recovery, chronic HBV carriers and chronic severe hepatitis B. The preS genes were amplified from serum samples with half nested PCR. The PCR products were cloned into M13 vectors and 10 cloneswere randomly selected for each individual and sequenced with standard methods. A total of 90 clones were sequenced and analyzed by DNA homological comparison. Results: The characteristics of the preS genes were significantly different in HBV-infected individuals with different clinical consequences.①As for acute hepatitis B, thepreS function domains were stable and no changes in epitopes for T and B cells were found. ②For chronic HBVcarriers, the function domains within preS proteins showed potentially changes with epitope drifts of T and B cellsbecause of the high variation of HBV preS genes. ③For chronic severe hepatitis B, there were special changes inthe function domains of B cells. The abnormally high immune response would cause severe liver injury in these individuals. Conclusion: This study provides experimental evidence for researches about the possible association ofvariation of preS1/S2 functional regions with clinical consequences.
文摘目的探讨包含前S1、前S2和S抗原的新型重组乙型肝炎疫苗(简称SS1S2疫苗)在小鼠中诱导体液和细胞免疫应答的能力以及在无应答小鼠中的免疫原性。方法以不同剂量(2.0、0.5、0.125、0.03μg)的SS1S2疫苗或商品化单S乙型肝炎疫苗(简称S疫苗)免疫BALB/c小鼠,于免后1、2、4周时采血,采用ELISA法检测两组疫苗单只小鼠血清的S、前S1和前S2抗体。以SS1S2疫苗或单S疫苗于0和3周时免疫BALB/c小鼠,每只5μg,于每次免疫后1周处死一半小鼠,制备脾脏淋巴细胞,采用ELISPOT法检测分泌IFNγ的细胞毒T淋巴细胞(cytotoxic T lymphocyte,CTL)频数。以单S疫苗于0、2、4周时免疫NIH小鼠,于末次免疫后4周采血,测定S抗体,筛选无应答小鼠。将无应答小鼠分为两组,分别用SS1S2疫苗或单S疫苗加强免疫1次,于免后1个月采血,测定S抗体。结果免后1、2周,2.0、0.5、0.125μg的SS1S2疫苗组S抗体阳转率均高于同剂量的单S疫苗组,且能诱导前S1、前S2抗体产生,而单S疫苗组无前S1、前S2抗体产生;免后4周,两组疫苗的抗体阳转率在总体上继续增加,2.0、0.5、0.125μg的SS1S2疫苗组S抗体几何平均滴度(GMT)均高于同剂量的单S疫苗组,且有一定滴度的前S1、前S2抗体,而单S疫苗组无前S1、前S2抗体产生。初免后1、4周,SS1S2疫苗组小鼠IFNγ分泌细胞频数均明显高于单S疫苗组(P<0.05或<0.01)。以0.5μg SS1S2疫苗或单S疫苗对经3剂单S疫苗免疫无应答NIH小鼠进行1次加强免疫后,SS1S2疫苗组小鼠抗体阳转率和GMT均明显高于单S疫苗组(P均<0.01)。结论与商品化单S乙肝疫苗相比,SS1S2疫苗在小鼠中诱导的抗体产生时间较早,抗体阳转率和抗体滴度较高,还能诱导前S1、前S2抗体产生;SS1S2疫苗比单S疫苗诱导了更高水平的特异性CTL应答;在无应答小鼠中能诱导更大比例和更高滴度的保护性抗体产生,表现出更好的免疫原性。
文摘乙型肝炎病毒(Hepatitis B Virus,HBV)外膜蛋白含PreS1、PreS2和S 3种蛋白,位于病毒颗粒的外表面,参与病毒颗粒的吸附、组装与成熟,在保护性免疫应答反应中起重要作用,HBV感染肝细胞所合成的外膜蛋白对肝细胞的生长、代谢,甚至是恶性转化产生一系列重要的生物学调节效应,外膜蛋白的变异使得HBV对受染肝细胞的影响非常复杂且成多样化,在病毒性乙型肝炎慢性化及其相关疾病演变过程的分子病理机制扮演重要角色。
