T cell responses and viral variability in blood donation candidates with occult

StephenW

J Hepatol. 2011 Dec 12. [Epub ahead of print]
T cell responses and viral variability in blood donation candidates with
occult hepatitis B infection.
Source:
http://www.ncbi.nlm.nih.gov/pubmed/22173156 Bes M, Vargas V, Piron M,
Casamitjana N, Esteban JI, Vilanova N, Pinacho A, Quer J, Puig L, Guardia
J, Sauleda S. SourceBanc de Sang i Teixits, Institut Català de la Salut,
Barcelona, Spain; Universitat Autònoma de Barcelona. Bellaterra, Spain;
Centro de investigación biomédica en red de enfermedades Hepáticas y
Digestivas (CIBEREHD) del Instituto de Salud Carlos III, Spain.

Abstract
BACKGROUND/AIMS: Occult HBV infection (OBI) is defined by the presence of
HBV DNA in liver and/or serum and negative HBsAg testing. Since
implementation of highly sensitive HBV DNA screening, OBI is also detected
in healthy blood donors. The aims of this study were to investigate
HBV-specific immune responses and genetic variability in donors with OBI,
established by HBV DNA in serum.

METHODS: HBV-specific T-cell responses to HBV antigens were tested in 34
OBI donors by IFN-? ELISpot, cytometric bead array, and intracellular
cytokine staining. As comparison populations, 36 inactive HBV carriers, 22
donors with spontaneously resolved HBV infection, 24 vaccinated donors, and
25 seronegative donors were also included. Surface, pre-S, and pre-c/core
genes from 44 genotype D isolates (24 OBI and 20 HBsAg-positive) were
sequenced.

RESULTS: Immune response of OBI donors to the 3 HBV antigens was 29%-41%,
similar to the response in subjects with resolved HBV infection and higher
than that in HBsAg-positive subjects. On sequence analysis, OBI donors
presented a higher HBsAg mutation rate than HBsAg-positive subjects.
Mutations were clustered in the major hydrophilic region of HBsAg, and no
stop codons or relevant mutations that could affect antigen formation or
detection were observed.

CONCLUSIONS: Our results suggest that immune response can suppress viral
replication to low levels and HBsAg expression to undetectable levels in
OBI blood donors. Relevant mutations were not found in the genomic HBsAg
coding region. Hence, the fact that HBsAg was not detected in OBI is likely
due to low HBsAg production, rather than to a failure of laboratory
reagents.

StephenW

J肝胆病。 2011年12月12日。 [检索提前打印]
T细胞应答和病毒变异与献血候选人
隐匿性乙肝病毒感染。来源：
http://www.ncbi.nlm.nih.gov/pubmed/22173156贝斯男，巴尔加斯五，派伦中号，
Casamitjana氮，埃斯特班姬，比拉诺瓦ñ，Pinacho一个曲儿，J，普格L时，迪亚
J，Sauleda S. SourceBanc生我Teixits，加泰罗尼亚语学院DE LA SALUT
巴塞罗那，西班牙;大学巴塞罗那自治。 Bellaterra，西班牙;
中心调查biomédica EN红色DE enfermedades Hepáticas Ÿ
Digestivas（CIBEREHD）DEL研究所Salud的卡洛斯三世，西班牙。

摘要
背景/目的：隐匿性HBV感染（OBI）是指存在
HBV DNA的肝脏和/或血清和阴性乙肝表面抗原检测。自
高度敏感的HBV - DNA检查的实施，欧倍德也检测
健康献血者。这项研究的目的是要调查
HBV特异性免疫反应和遗传变异与欧倍德的捐助者，
建立了血清中HBV DNA。

在34个测试方法：HBV特异性T细胞反应HBV抗原
干扰素通过欧倍德捐助者的呢？ ELISPOT，式微珠阵列，细胞内
细胞因子染色。由于比较的人口，36不活跃的乙肝病毒携带者，22
与HBV感染自发解决捐助者，24位接种疫苗的捐助者，
25血清阴性的捐助者也包括在内。表面，前S，和pre-c/core
来自44个基因型D的分离（24欧倍德和20例HBsAg阳性）的基因
测序。

结果：欧倍德捐助3 HBV抗原的免疫反应率为29％-41％，
类似的解决乙肝病毒感染受试者的反应和较高的
乙肝表面抗原阳性者。序列分析，欧倍德捐助者
呈现较高的乙肝表面抗原突变率比乙肝表面抗原阳性者。
突变聚集的HBsAg主要亲水区，并没有
终止密码子或相关的基因突变可能影响抗原的形成或
检测观察。

结论：我们的研究结果表明，可以抑制病毒的免疫反应
复制水平低和HBsAg的表达，在检测不到的水平
欧倍德血液捐助者。未发现相关基因突变在基因组乙肝表面抗原
编码区。因此，在欧倍德检测，乙肝表面抗原的事实是可能的
由于低HBsAg的生产，而不是一个实验室的失败
试剂。