Institute of Virology, Helmholtz Zentrum München, Munich, Germany.
German Center for Infection Research (DZIF), Munich, Germany.
Front Immunol. 2021 Sep 10;12:713351. doi: 10.3389/fimmu.2021.713351. eCollection 2021.
The cellular mechanisms involved in the lack of protective antibody response after hepatitis B vaccination are still rather unclear. Regulatory B cells (Breg) known as modulators of B-and T-cell responses may contribute to poor vaccine responsiveness. The current study aimed to investigate the role of regulatory B cells (Breg) in hepatitis B vaccine non-responsiveness after immunization with second- or third-generation hepatitis B vaccines.
We performed comparative phenotypic and frequency analysis of Breg subsets (CD24CD27 and CD24CD38 Breg) in second-generation hepatitis B vaccine non-responders (2 HBvac NR, n = 11) and responders (2 HBvac R, n = 8) before (d0), on day 7 (d7), and 28 (d28) after booster vaccination. Cryopreserved peripheral blood mononuclear cells were stimulated with a combination of CpG, PMA, and Ionomycin (CpG+P/I) and analyzed for numbers and IL-10 expression levels of Breg by flow cytometry-based analyses.
Flow cytometry-based analyses revealed elevated frequencies of CD24CD27 Breg at all time points and significantly higher frequencies of CD24CD38 Breg on d0 ( = 0.004) and 28 ( = 0.012) in 2 HBvac NR compared to 2 HBvac R. In parallel, we observed significantly lower levels of CpG+P/I-induced IL-10 expression levels of CD24CD27 and CD24CD38 Breg (d0: < 0.0001; d7: = 0.0004; d28: = 0.0003 and d0: = 0.016; d7: = 0.016, respectively) in 2 HBvac NR compared to 2 HBvac R before and after booster immunization. Frequencies of CD24CD27 and CD24CD38 Breg significantly decreased after third-generation hepatitis B booster vaccination (d7: = 0.014; d28: = 0.032 and d7: = 0.045, respectively), whereas IL-10 expression levels of both Breg subsets remained stable.
Here we report significantly higher frequencies of CD24CD38 Breg in parallel with significantly lower IL-10 expression levels of CD24CD27 and CD24CD38 Breg in 2 HBvac NR compared to 2 HBvac R. Anti-HBs seroconversion accompanied by a decrease of Breg numbers after booster immunization with a third-generation hepatitis B vaccine could indicate a positive effect of third-generation hepatitis B vaccines on Breg-mediated immunomodulation in hepatitis B vaccine non-responders.
乙型肝炎疫苗接种后缺乏保护性抗体反应的细胞机制仍相当不清楚。调节性 B 细胞（Breg）作为 B 细胞和 T 细胞反应的调节剂，可能与疫苗反应不良有关。本研究旨在探讨调节性 B 细胞（Breg）在第二代和第三代乙型肝炎疫苗免疫后乙型肝炎疫苗无应答中的作用。
我们对第二代乙型肝炎疫苗无应答者（2 HBvac NR，n = 11）和应答者（2 HBvac R，n = 8）在加强免疫前（d0）、第 7 天（d7）和第 28 天（d28）进行了 Breg 亚群（CD24CD27 和 CD24CD38 Breg）的比较表型和频率分析。用 CpG、PMA 和离子霉素（CpG+P/I）组合刺激冷冻保存的外周血单核细胞，并通过流式细胞术分析 Breg 的数量和白细胞介素-10 表达水平。
流式细胞术分析显示，在所有时间点，CD24CD27 Breg 的频率均升高，而在 2 HBvac NR 中，CD24CD38 Breg 的频率在 d0（=0.004）和 28（=0.012）时明显更高。同时，我们观察到 CpG+P/I 诱导的 CD24CD27 和 CD24CD38 Breg 的白细胞介素-10 表达水平明显降低（d0：<0.0001；d7：=0.0004；d28：=0.0003 和 d0：=0.016；d7：=0.016）在 2 HBvac NR 中与 2 HBvac R 相比，在加强免疫前后。第三代乙型肝炎疫苗加强免疫后，CD24CD27 和 CD24CD38 Breg 的频率明显下降（d7：=0.014；d28：=0.032 和 d7：=0.045），而这两个 Breg 亚群的白细胞介素-10 表达水平保持稳定。
本研究报道了 2 HBvac NR 中 CD24CD38 Breg 的频率明显升高，同时 CD24CD27 和 CD24CD38 Breg 的白细胞介素-10 表达水平明显降低，与 2 HBvac R 相比。第三代乙型肝炎疫苗加强免疫后抗-HBs 血清转化伴随着 Breg 数量的减少，这可能表明第三代乙型肝炎疫苗对乙型肝炎疫苗无应答者的 Breg 介导的免疫调节有积极影响。
