HBV疫苗接种后机体T细胞应答和TCR CDR3受体库特征的研究进展

接种HBV疫苗诱导机体免疫应答,产生保护性的HBsAb是预防HBV感染最重要的措施。T细胞在HBV疫苗应答过程中发挥极为重要的作用,这与个体HBsAb滴度的水平密切相关。该文就T细胞对HBV疫苗的应答以及形成的T细胞受体互补决定区3(T cell receptor complementarity determining region 3,TCR CDR3)受体库特征的研究概况和进展进行综述。     

T细胞抗原受体β链互补决定区3受体库高通量测序分析及其在重要疾病中的研究应用

T细胞受体(TCRs)既是T细胞特异性识别和连接抗原的分子,也是T细胞发生免疫应答的关键分子.其中TCR高变区的CDR3变异最大,最能代表T细胞的应答特征,其在外周形成了具有多样性的T细胞CDR3受体库.因此,对T淋巴细胞β链CDR3组库的研究,以期更好地理解疾病的发病机理,并对疾病的临床诊断和治疗、监测疾病提供理论基础和新的思路.     

三种人乳头瘤病毒疫苗接种后T、 B细胞应答差异的研究进展

宫颈癌是全球女性常见癌症之一,高危型人乳头瘤病毒16(HPV16)、 HPV18的长期感染是宫颈癌的主要病因,目前广泛应用的HPV疫苗主要有2价Cervarix疫苗、 4价Gardasil疫苗及9价Gardasil-9疫苗,三种疫苗接种后在T细胞效应分子变化,B细胞产生的抗体水平、持续时间、年龄及接种针剂等方面存在差异。     

B7-2表达质粒对HBV DNA疫苗诱导的特异性免疫应答的影响

目的：探讨B7－2分子是否能够增强乙型肝炎病毒（HBV）DNA疫苗诱导的特异性免疫应答。方法：将B7－2表达质粒与HBV DNA疫苗共接种于小鼠腓肠肌内，检测细胞毒性T淋巴细胞（CTL）活性，迟发性超敏反应（DTH）及抗－HBs滴度。结果：B7－2表达质粒与HBV DNA疫苗共接种组的DTH反应和CTL活性，明显强于单独接种HBV DNA疫苗组（P＜0．01）。两组的抗－HBs滴度差异无显著性（P＞0．05）。结论：B7－2表达质粒与HBV DNA疫苗共接种可显著增强抗－HBV特异性细胞免疫应答（CMI）。     

慢性乙型肝炎患者外周血CD8~+T细胞TCR Vβ基因亚家族克隆化的研究

目的:分析慢性乙型肝炎(CHB)患者CD8+T细胞TCR Vβ基因亚家族克隆化特征。方法:采用逆转录-聚合酶链反应(RT-PCR)扩增8例CHB患者外周血CD8+T细胞TCR Vβ基因22个亚家族的CDR3区,基因扫描技术对TCR Vβ亚家族的克隆化进行鉴定。结果:基因扫描显示所有8例CHB患者CD8+T细胞TCR Vβ基因亚家族均出现一个或一个以上单克隆或寡克隆增生。Vβ8、Vβ11、Vβ12出现单克隆增生的频率相对较高。8例健康者TCR Vβ基因亚家族均为多克隆。结论:CHB患者外周血CD8+T细胞TCR Vβ亚家族存在克隆性增生。     

无症状HBV携带者外周血CD4~+TCR Vβ基因亚家族克隆化特征的研究

分析无症状HBV携带者(AsC)CD4+TCR Vβ基因家族克隆化特征。采用逆转录-聚合酶链反应(RT-PCR)扩增7例AsC外周血CD4+TCR Vβ基因22个亚家族的CDR3区,基因扫描技术对CD4+TCR Vβ亚家族的克隆化进行鉴定。结果基因扫描显示,7例AsC CD4+TCR Vβ基因亚家族均出现一个或一个以上单克隆或寡克隆增生;7例健康者CD4+TCR Vβ基因亚家族均呈正态分布。提示,AsC外周血CD4+TCR Vβ亚家族存在克隆性增生,这可能与AsC免疫耐受的形成有关。     

乙肝疫苗免疫失败儿童病毒S基因"a"决定簇变异研究

目的 探讨江苏常州地区乙型肝炎疫苗免疫失败儿童病毒S基因“a”决定簇的变异情况。方法 对15例乙肝疫苗接种后血清表面抗原(HBsAg)阳性的儿童,采用聚合酶链反应方法(PCR)扩增其血清中HBV DNA S基因区。并对PCR产物直接标记测序。结果 15例HBsAg阳性儿童有14例血清HBV DNA阳性,其中有4例出现了S基因“a”决定簇的变异,变异率为28．6％,第126位的异亮氨酸（Ile)被苏氨酸(Thr)替代1例,第134位苯丙氨酸(Phe)被异亮氨酸替代1例。第145位甘氨酸(Gly)被丙氨酸(Pha)替代2例。结论乙型肝炎疫苗免疫失败儿童中存在s基因“a”抗原决定簇变异,江苏常州地区存在HBVS基因“a”决定簇变异的新类型。     

Lack of awareness of Hepatitis B screening and vaccination in high-risk groups

Background/aim Hepatitis B virus (HBV) vaccination rates are insufficient in high-risk patients worldwide. This study aimed to investigate the screening, immunization, and vaccination rates in three high-risk groups for HBV infection: allogeneic hematopoietic stem cell transplantation (AHSCT), renal transplantation (RT), and chronic hepatitis C (CHC) groups. Materials and methods The serological data of consecutive patients between 2014 and 2019 were reviewed using the hospital database. Results The HBV screening rates were 100.0%, 90.4%, and 82.4% in the AHSCT, CHC, and RT groups, respectively (p = 0.003). The immunization rates against HBV through either previous exposure or vaccination were 79.5%, 71.7%, and 46.5% in the AHSCT, RT, and CHC groups, respectively (p < 0.001). The HBV vaccination rate was significantly low in the CHC group (71.5%, 69.0%, 34.6% in the AHSCT, RT, and CHC groups, respectively, p < 0.001). If patients lost their immunity due to immunosuppressive therapy were accounted, the vaccination rates increased to 95.2% in the AHSCT group and 72.9% in the RT group. The rate of annual screening for HBV status was 97.9% in the AHSCT group, but it was only 23.9% in the RT group. Conclusion HBV screening and vaccination rates were significantly lower in the RT and CHC groups than in the AHSCT group.     

乙型肝炎疫苗免疫19年后乙型肝炎病毒感染流行规律的变化

目的探讨乙肝疫苗长期免疫地区人群HBV流行规律的变化趋势。方法整群抽样结合横断面调查，用固相放射免疫法检测研究对象血清HBV感染标志并进行分析。结果（1）平均HBsAg阳性率为7．5％，0～19岁人群HBV感染指标显著低于≥20岁人群。（2）0～19岁人群HBsAg阳性率1985年高于2005年；1985年的抗-HBs水平随着年龄增长而上升，从1～岁组的12．4％到60～岁组的53．8％，而2005年0～19岁组的抗-HBs随着年龄的增长而下降；1985年抗-HBc阳性水平随着年龄增长而上升，2005年的0～19岁组的仅为2．8％～26．8％，显著下降。结论研究人群中HBV流行规律发生显著变化，0～19岁人群的HBV感染率远低于20岁以上人群，证实乙肝疫苗预防HBV感染取得显著成果。     

Hepatitis B vaccination in children: The Taiwan experience

The world's first nationwide hepatitis B virus (HBV) universal vaccination program for infants was launched in Taiwan in July, 1984. All infants received three to four doses plasma or recombinant HBV vaccines. In addition, infants of HBeAg-positive mothers received 0.5 ml of hepatitis B immunoglobulin within 24 hours after birth. The vaccination coverage rate is as high as 97%. Seroprevalence of hepatitis B surface antigen (HBsAg) declined from 9.8% (prevaccination period) to 0.6% in children in Taipei City after 20 years of mass vaccination. The seropositive rates for HBsAg, antibody to HBsAg, and antibody to hepatitis B core antigen were 1.2%, 50.5%, and 3.7%, respectively, in those born after the vaccination program (< 20 years old) in 2004. In line with the decrease of chronic HBV infection, the incidence of hepatocellular carcinoma (HCC) also decreased in children in Taiwan. From 1981 to 1994, the incidence of HCC in 6- to 9-year-olds declined from 0.52/100,000 for those born between 1974 and 1984 to 0.13 for those born between 1984 and 1986 (p < 0.001). We extended the observation to 2000, the incidence of HCC per 100,000 children declined from 0.54 to 0.20. The prevalence of a determinant mutants (amino acids 121–149 of HBsAg) in Taiwanese carrier children was 7.8% (eight out of 103) in 1984, increased to 19.6% (10 out of 51) in 1989, peaked at 28.1% (nince out of 32) in 1994, and remained stationary at 23.1% (three out of 13) and about 25% in 1999 and 2004, respectively; it was higher in those fully vaccinated compared with those not vaccinated. The other group of subjects who are susceptible to vaccine failure is the immunocompromized hosts. We observed some de novo HBV infection in children after liver transplantation. Despite of the success of hepatitis B immunization, childhood chronic HBV infection and HCC were not eliminated by the universal vaccination program. Among those HBsAg carriers born after the vaccination program, 89% of their mothers were found to be positive for HBsAg, indicating the importance of maternal transmission. This was also true in the mothers of children with HCC, of them 96% were HBsAg positive. After two decades of universal infant HBV vaccination, we found this program provides long-term protection for up to more than 20 years, and a universal booster is not required for the primary HBV vaccinees before adulthood. Mother-to-child transmission, although largely diminished, is still the main cause for immunoprophylaxis failure. The emergence of escape mutant did not impose increased risk of chronic infection at present. Nevertheless, development of new vaccines may overcome the vaccine failure.     

慢性乙型肝炎患者外周血树突状细胞功能状态与HBV载量的关系

目的：探讨慢性乙型肝炎（CHB）患者外周血树突状细胞功能状态与HBV载量的关系。方法：采集23例CHB患者和8例健康人的抗凝外周静脉血，分离外周血单个核细胞（PBMCs），在重组人白细胞介素4和重组人粒细胞-巨噬细胞集落刺激因子的作用下培养使DCs增殖、成熟，以间接免疫荧光流式细胞技术分别检测DCs表面CD80、CD86、HLA-DR及ICAM-1的表达；以ELISA法检测DCs培养上清液中IL-12的水平；将培养成熟的DCs与HBsAg共同孵育，用丝裂霉素C处理后再与自体PBMCs共同培养，在培养结束前12小时加入^3H-TDR，收集细胞，以β液闪计数仪测定cpm值；同期用定量聚合酶链反应技术测定CHB患者外周血HBV载量。结果：患者DCs表面CD86、HLA-DR和ICAM-1的表达水平，DCs的抗原提呈能力及其分泌IL-12的水平均显著低于健康对照组；CD80、CD86、HLA-DR及ICAM-1的表达与HBV载量呈显著负相关关系（分别为P〈0．01、P〈0．01、P〈0．001和P〈0．001）；DCs的抗原提呈能力及其分泌IL-12的水平也与HBV载量呈显著负相关关系（分别为P〈0．001和P〈0．01）。结论：CHB患者外周血DCs的成熟和功能存在障碍，DCs的功能状态与血液中HBV的载量密切相关，并可能对HBV的清除产生重要的影响。     

乙型肝炎患者HBV M和HBV DNA的相关性研究

目的 探讨乙型肝炎患者的乙型肝炎病毒（ＨＢＶ）血清学标志（ＨＢＶ Ｍ）与ＨＢＶ ＤＮＡ检测结果的相关性与临床意义。方法 对４１４例乙型肝炎的ＨＢＶ Ｍ和ＨＢＶ ＤＮＡ检测结果进行比较。ＨＢＶ Ｍ用ＥＬＩＳＡ定量分析法检测,ＨＢＶ ＤＮＡ用斑点杂交法检测。结果 急性、慢性乙型肝炎患者中ＨＢＶ ＤＮＡ的阳性率与乙型肝炎肝硬化患者的ＨＢＶ ＤＮＡ阳性率比较,差异有显著性;ＨＢｓＡｇ、抗－ＨＢｅ、抗－ＨＢｃ阳性和ＨＢｓＡｇ、ＨＢｅＡｇ、抗－ＨＢｃ阳性组的ＨＢＶ ＤＮＡ阳性率比较,差异无显著性;ＨＢｓＡｇ和／或ＨＢｅＡｇ的滴度与ＨＢＶ ＤＮＡ阳性率呈正相关关系。结论 ＨＢＶ ＤＮＡ是评价ＨＢＶ活动最理想的标志;抗－ＨＢｅ的出现不能作为ＨＢＶ复制停止的指标;ＨＢｓＡｇ的滴度和ＨＢｅＡｇ的滴度变化可作为临床评价病毒复制程度和     

HBV对树突状细胞的作用导致乙肝慢性化

近年来,对于HBV与DC间的作用机制有了一系列的进展,作为免疫系统的哨兵,DC在抗HBV免疫的产生中具有重要意义。HBV感染期间,DC在功能上发生了改变,HBV即通过改变DC功能逃避天然和固有免疫。在这篇综述中,我们突出了HBV与DC间相互作用的具体机制,以进一步阐明乙肝慢性化的原因。     

Absence of anti-hepatitis B surface antibody after vaccination does not necessarily mean absence of immune response

A small number of subjects vaccinated against hepatitis B do not produce anti-hepatitis B surface (HBs) antibody levels detectable by commercial assays. Others lose detectable anti-HBs at some time after vaccination. The absence of clinical hepatitis despite potential exposure to hepatitis B virus (HBV) in both kinds of subjects suggests that they might be protected by low antibody levels. However, besides anti-HBs, T helper response and memory cells which may be induced by the vaccine are certainly also important for immunity against HBV. In the present study, samples from vaccinated subjects, found to be anti-HBs negative in an initial assay, subsequently showed positive results in, respectively, 25%, 36% and 38% of the cases, when a second, third and fourth assay was used. In addition, 360 samples from “nonresponders” and from vaccinees who had lost anti-HBs, the reactivity of which was under the enzyme-linked immunoassay-cut-off value were compared to that of nonvaccinated controls. The absorbances were found to be significantly higher in the nonresponders (0.038) and in the vaccinees having lost anti-HBs (0.041), than in the controls (0.025). Such findings contribute to explaining why so-called nonresponders as well as vaccinees who have lost anti-HBs nevertheless appear to be protected. Received: 16 June 2000     

Seroprevalence of hepatitis B virus infection in children in Taipei, 1989: five years after a mass hepatitis B vaccination program

A nationwide hepatitis B vaccination program was launched in Taiwan in 1984. To study the impact of this ongoing program on hepatitis B virus (HBV) infection, a follow-up seroepidemiologic study was carried out in 1989 in a Taipei district where pre-vaccination seroepidemiology had been studied. HBV markers were studied in 1134 apparently healthy children (619 boys and 515 girls) under 13 years of age between March and July 1989. The prevalence of hepatitis B surface antigen (HBsAg) in children under 5 years of age decreased from 9.3% in 1984 to approximately 2% in 1989. A significant decrease in HBsAg prevalence and hepatitis B core antibody in 5- to 8-year-old children who were not immunized against HBV showed that horizontal infection among the older children had also decreased. Thus, this program not only protected vaccinated subjects; the reduction in numbers of highly infectious young HBV carriers also contributed to a lower prevalence of hepatitis B infection and carrier rates in some older children. This study demonstrates that hepatitis B vaccination is effective in protecting the majority of children in hyperendemic areas from HBV infection and from becoming chronic carriers.     

乙肝疫苗增强细胞因子诱导的杀伤细胞对于转乙型肝炎病毒基因小鼠的治疗作用

目的 观察乙肝疫苗是否增强细胞因子诱导的杀伤细胞(cytokine-induced killer cell,CIK)对于乙型肝炎病毒转基因小鼠(hepatitis B virus transgenic mice,HBV-Tg)的抗病毒作用.方法 给予HBV-Tg腹腔注射CIK细胞,皮下注射乙肝疫苗,用荧光定量PCR检测外周血中HBV DNA水平变化,流式细胞仪检测外周血中T淋巴细胞亚群,并用HE染色观察肝脏的组织病理改变.结果 CIK细胞降低了HBV-Tg鼠外周血中病毒载量,血中CD3~+、CD4~+及CD8~+细胞增多,乙肝疫苗和CIK细胞联合应用后,这种作用增强.结论 乙肝疫苗增强了CIK对于HBV-Tg小鼠的治疗作用,这种增强作用是否通过增加体内CD3~+、CD4~+及CD8~+细胞,尤其是CD8~+细胞而实现,有待进一步研究.