Comparative characterization of B cells specific for HBV nucleocapsid and envelope proteins in patients with chronic hepatitis B
Comparative characterization of B cells specific for HBV nucleocapsid and envelope proteins in patients with chronic hepatitis B
复制标题
DOI：
10.1016/j.jhep.2019.07.015
复制
发表时间：
2020-01-01
影响因子：
25.7
通讯作者：
Bertoletti, Antonio
中科院分区：
文献类型：
--
作者：
Le Bert, Nina;Salimzadeh, Loghman;Bertoletti, Antonio
背景与目的：对乙肝病毒自然感染过程中抗-HBs体液免疫的调节知之甚少。我们最近利用双重荧光标记的乙肝表面抗原，在慢性乙肝(CHB)感染的患者中，显示了他们的乙肝表面抗原特异性B细胞的功能损害。然而，他们的HBcAg特异性B细胞的特征尚不清楚。我们建立了一种直接可视化、筛选和鉴定HBcAg特异性B细胞的方法。方法：合成荧光标记的HBcAg试剂，直接检测36例CHB患者体内HBcAg特异性B细胞。采用流式细胞术、体外成熟试验和纳米串检测免疫基因的表达等方法，对HBcAg特异性B细胞的频率、表型、功能成熟和转录谱进行了研究，并与HBs Ag特异性B细胞和总B细胞进行了比较。结果：在CHB患者中，HBcAg特异性B细胞的出现频率高于HBs Ag特异性B细胞，而且与HBs Ag特异性B细胞不同，HBcAg特异性B细胞在体外能高效成熟为抗体分泌细胞。它们的表型和转录图谱表明，HBcAg特异性B细胞优先是Ig G+记忆性B细胞。然而，尽管慢性乙肝患者的HBcAg和HBs Ag特异性B细胞在表型和功能上存在差异，但它们具有不同于全局记忆B细胞的mRNA表达模式，具有交叉呈递和天然免疫活性的高表达基因的特点。结论：在慢性乙肝感染过程中，抗-HBs和抗-HBc抗体的血清学检测与其各自特异性B细胞的数量和功能存在直接关系。然而，对HBs Ag和HBcAg特异的B细胞进行的转录分析表明，除了产生抗体外，乙肝病毒特异的B细胞还有其他作用。在慢性乙肝病毒感染期间，可以检测到针对病毒内部部分(核心或HBcAg)的抗体，而不存在针对病毒包膜(表面或HBs Ag)的抗体。在这里，我们开发了一种方法，使我们能够在体外直接可视化这两种病毒成分所特有的B细胞，突出它们的异同，并展示同一病毒的两种成分如何对抗病毒B细胞的功能产生不同的影响。(C)2019年欧洲肝脏研究协会。爱思唯尔出版，版权所有。
Background & Aims: Knowledge about the regulation of anti-HBV humoral immunity during natural HBV infection is limited. We recently utilized dual fluorochrome-conjugated HBsAg to demonstrate, in patients with chronic HBV (CHB) infection, the functional impairment of their HBsAg-specific B cells. However, the features of their HBcAg-specific B cells are unknown. Here we developed a method to directly visualize, select and characterize HBcAg-specific B cells in parallel with HBsAg-specific B cells.Methods: Fluorochrome-conjugated HBcAg reagents were synthesized and utilized to directly detect ex vivo HBcAg-specific B cells in 36 patients with CHB. The frequency, phenotype, functional maturation and transcriptomic profile of HBcAg-specific B cells was studied by flow cytometry, in vitro maturation assays and NanoString-based detection of expression of immune genes, which we compared with HBsAg-specific B cells and total B cells.Results: HBcAg-specific B cells are present at a higher frequency than HBsAg-specific B cells in patients with CHB and, unlike HBsAg-specific B cells, they mature efficiently into antibody-secreting cells in vitro. Their phenotypic and transcriptomic profiles show that HBcAg-specific B cells are preferentially IgG+ memory B cells. However, despite their phenotypic and functional differences, HBcAg- and HBsAg-specific B cells from patients with CHB share an mRNA expression pattern that differs from global memory B cells and is characterized by high expression of genes indicative of cross-presentation and innate immune activity.Conclusions: During chronic HBV infection, a direct relation exists between serological detection of anti-HBs and anti-HBc antibodies, and the quantity and function of their respective specific B cells. However, the transcriptomic analysis performed in HBsAg- and HBcAg-specific B cells suggests additional roles of HBV-specific B cells beyond the production of antibodies.Lay summary: Protection of viral infection necessitates the production of antibodies that are generated by specialized cells of the immune system called B cells. During chronic HBV infection, antibodies against the internal part of the virus (core or HBcAg) are detectable while the antibodies directed against the virus envelope (surface or HBsAg) are not present. Here we developed a method that allows us to directly visualize ex vivo the B cells specific for these 2 viral components, highlighting their differences and similarities, and showing how 2 components of the same virus can have different impacts on the function of antiviral B cells. (C) 2019 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.