重组质粒pcDNA3．1S2S／Fc在小鼠诱导免疫反应的观察

目的探讨S2S／Fc融合基因疫苗诱导小鼠HBV preS2S特异性体液和细胞免疫应答情况。方法取pcDNA3．1S2S/Fc、pcDNA3．1S2S＋pCMVsFc、pcDNA3．1S2S和空载体对照免疫BALB／c小鼠。在免疫动物2,4和6周后检测血清抗-HBs水平;在初次免疫7周后,测定免疫脾细胞的杀伤活性、增殖活性及细胞因子的分泌水平。结果经pcDNA3．1S2S／Fc免疫小鼠6周抗体滴度升至最高,免疫脾细胞的杀伤活性在效靶比为20：1时最高,免疫脾细胞的增殖活性以及IL-2和IFN-γ的分泌水平均比对照组明显增高。结论S2S／Fc融合基因在小鼠能诱导很强的特异性体液和细胞免疫应答。     

Characteristics of immune memory 10–15 years after primary hepatitis B vaccination

Background and aimsThe definition of immune memory after hepatitis B vaccination is still under debate. Therefore, we analysed hepatitis B surface antigen (HBsAg)-specific memory in more detail by investigating the kinetics of humoral and cellular responses after hepatitis B booster vaccination.MethodsThe anti-HBs kinetics of 23 individuals with anti-HBs titres below 10 IU/l, who had been vaccinated 10–15 years ago, was monitored at day 0, 3, 7, 14 and 28 after booster vaccination. HBsAg-specific IFNγ- and IL5-secreting cells in enriched CD4⁺ fraction were measured at day 0, 7 and 28 post-booster by enzyme-linked immunospot assay (ELISpot).Results22 of 23 subjects showed similar anti-HBs kinetic curves, including 3 of 4 subjects who did not reach anti-HBs titres of 10 IU/l. The steep anti-HBs increase started between day 3 and 7 and peaked around day 14. A plateau or only minimal changes were visible between day 14 and 28. 17.4% of subjects showed pre-booster cellular responses, and this rate had increased to 47.8% and 56.5% after 7 and 28 days, respectively. The kinetic patterns of T cell responses differed considerably among subjects. A dominance of Th2 responses (IL5 secretion) over Th1 responses (IFNγ secretion) could be observed.ConclusionsThe presence of B cell memory could be shown by a typical anamnestic anti-HBs response curve after a booster dose in all but one individual. In contrast, T cell responses to booster vaccination, which occurred in approximately 50% of participants, were rather heterogeneous.     

Hepatitis B vaccination at three months of age: A successful strategy?

Vaccination of infants, children and adolescents against the hepatitis B virus (HBV) is mandatory in Italy. It is crucial to assess whether vaccinated subjects have protective antibody level during adulthood when the risk of HBV infection increases due to lifestyle or occupational exposure. Two groups of students attending to University of Padova Medical School were enrolled between 2004 and 2011 and HBV antibodies and antigens were measured. The first group (Group A) comprised students vaccinated at three months of age and the second group (Group B) comprised students vaccinated after the first year of life. The follow-up was 18.0 (Group A) and 17.9 (Group B) years. The students vaccinated at three months of age had a higher rate of non-protective antibodies (47.2%) comparing to those vaccinated after the first year of life (17.0%, P < 0.0001) with a significantly lower antibody level (P < 0.001). The rate of non-protective antibodies was inversely related to vaccination age. The results clearly show that children vaccinated after the first year of life are better protected against HBV. On the other hand, both groups show a good immunological memory as evidenced by the achievement of protective antibody level after the booster dose in 97.8% of subjects.     

两种不同剂量国产乙肝血源疫苗接种法5年期间的免疫效果观察

目的：观察两种不同剂量乙肝血源疫苗接种法５年期间的免疫学效果。方法：以皮内接种３μｇ乙肝疫苗的１４６名儿童为观察组，对照组为肌注１０μｇ的５２名儿童，接种后随访观察５年后采血，检测乙肝３项指标和转氨酶（ＡＬＴ）。     

池州市农村0～2岁儿童乙型肝炎疫苗接种及其免疫效果评价

为了解池州市乙型肝炎 (乙肝 )疫苗接种现况和免疫效果 ,于 2 0 0 2年 12月 2 0日～ 2 0 0 3年 1月 2 0日 ,对所辖4个县 (区 ,下同 )进行了调查。 4个县 2 0个乡 (镇 )按 <1岁、1岁、2岁共抽查 4 2 0名儿童 ,检测乙肝病毒表面抗原(HBsAg)与抗体 (抗 HBs)。结果 :池州市农村儿童乙肝疫苗接种率达 99 2 9% ,首针及时接种率为 73 81% ;池州市农村乙肝疫苗接种主要有 3种方式 ,即分娩医院接种、首针分离接种和接种点接种 ,其中分娩医院接种和首针分离接种符合接种要求 ,其首针及时接种率 >93% ,全程及时接种率 >87% ;HBsAg阳性 3人 ,阳性率 0 71% ,抗 HBs阳性 2 75人 ,阳转率 6 5 4 8% ;另有 14 2名 (33 81% )儿童HBsAg和抗 HBs双阴性。因此加强农村儿童乙肝疫苗接种管理 ,明确分娩医院和接种点各自的职责 ,规范乙肝疫苗接种是确保乙肝疫苗纳入计划免疫后获得高质量、高效果的关键。同时提高农村孕妇住院分娩有助于提高儿童乙肝疫苗接种率。     

某高校大学生乙型肝炎疫苗接种后免疫效果观察

目的了解云南省某高校大学生乙型肝炎疫苗接种后乙型肝炎表面抗体(抗-HBs)产生状况,与其他报告比较以评价其免疫效果,探讨相关影响因素,找出合适的策略。方法采用试剂盒ELISA法测定血清中抗-HBs。结果390名检测对象抗-HBs总阳性率79.74%;男生和女生抗-HBs阳性率分别为76.47%、80.24%;汉族学生和少数民族学生抗-HBs阳性率分别为80.97%、75%;2000级、2001级、2002级、2003级抗-HBs阳性率分别为47.54%、83.5%、88.64%、84.04%。结论本次检测的390名大学生抗-HBs阳性率与普遍报道的基本接近,男生和女生、汉族和少数民族学生抗-HBs阳性率差异无显著性,不同年度接种疫苗的学生抗-HBs阳性率存在差异;应在接种前和接种过程中尽量避免人为因素干扰以提高抗-HBs阳性率;接种疫苗后应进行抗-HBs检测以确定免疫是否有效及随后的加强免疫时间确定。     

新生儿乙型肝炎疫苗全程免疫后抗-HBs低应答者的长期随访

为了解新生儿乙型肝炎（乙肝）疫苗全程免疫后抗－HBs低应答者的再感染情况和转归，为免疫预防措施提供依据，选取乙肝疫苗全程免疫后抗-HBs低应答者28例进行长期血清流行病学随访．结果有12例（42．86％）仍是HBsAg、抗-HBs和抗-HBc三项全阴性，也未发现HBV感染指征；5例（17．86％）出现了单项抗-HBsS／N值≥10．0以上的应答；11例（36．4％）发生HBV感染，其中4例（36．4％）变为持续阳性者，有1例为HBsAg阳性可能仍属母婴阻断失败者。表明抗-HBs低应答是个暂时现象，多数有潜伏感染，但预后是好的．     

1530名儿童抗-HBs定量检测结果研究

目的 了解1～15岁儿童乙肝病毒表面抗体(抗-HBs)阳性率,为乙肝疫苗加强免疫提供依据.方法 采用双抗原夹心时间分辨免疫荧光分析法对1 530例1～15岁儿童进行抗-HBs检测.结果 1～15岁儿童抗-HBs阳性率为60.26％.其中男性抗-HBs阳性率为55.88％,明显低于女性的64.45％(P＜0.01);1～6岁年龄组抗-HBs阳性率为64.00％,明显高于7～12岁年龄组的57.48％和13～15岁年龄组的57.14％ (P＜0.05),但7～12岁年龄组与13～15岁年龄组比较差异无统计学意义(P＞0.05);13～15岁年龄组与7～12岁年龄组和1～6岁年龄组的抗-HBs滴度水平比较,差异均无统计学意义(P＞0.05).结论 本地区儿童抗-HBs阳性率存在人群差异,可能与年龄、性别相关,且随年龄的增长而有所下降.     

表面抗原和抗体双阳性慢性乙型肝炎发生机制的研究进展

典型的慢性HBV感染血清学特征是存在HBsAg，而抗-HBs阴性，但近年来有关nSsAs和抗-HBs双阳性的慢性HBV感染的报道越来越多，其具体发生机制仍有争论，故本文就其可能的相关机制作以下综述。     

Hepatitis B surface antibodies seroprevalence among people born before and after implementation of universal HBV vaccination

Universal vaccination is the most effective strategy to control hepatitis B virus (HBV) infection. In Argentina, vaccination against HBV was incorporated in year 2000 for newborns and in 2003 for 11 years old children. However, there is a paucity of data about protection levels against HBV infection.The aim of this work was to determine the prevalence of seroprotective anti-HBs antibodies (aHBs) in Argentina.Serum samples negative for HBsAg and anti-HBc from 132 children born after year 2000 and 762 blood donors, older than 18 years, from five centers across the country, were analyzed for aHBs.Titers ≥10 mIU/mL were observed in 74/132 children (56.1%) and 336/762 (44.1%) in blood donors. The median age for blood donors was 33.9 (23–43); from them, 210 (27.6%) were born after 1992 and, therefore, were catch-up by vaccine implementation at 11 years old age. Donors born in 1992 or before showed a significantly lower frequency of protection (32.2%) compared to donors born after 1992 (75.2%), p < 0.0001. In addition, significant differences were observed in the status of seroprotection between different participating centers (p = 0.024).Implementation of HBV vaccine in 2000 and 2003 implied an overall increase of the aHBs seroprotective rates, with a particularly adequate response in children vaccinated at 11 years old age. The observed results suggest that population born in 1992 or before is currently the most susceptible. Consequently, it would be advisable to become aware of the risk of transmission in this age group and to stress this population vaccination campaigns.