乙型肝炎病毒(HBV)治疗的理想目标是HBsAg消失，但这并不容易实现。贫血是慢性乙型肝炎(CHB)患者常见的问题，会导致红细胞祖细胞(EPCs)增加和免疫抑制。本研究调查了PEG-干扰素α(PEG-IFN)治疗后EPCs在HBsAg清除中的作用。流式细胞术和免疫荧光试验发现CD45+EPCs在CHB患者和一个AAV/HBV小鼠模型的循环和肝脏中存在。Wright-Giemsa染色显示，这些病理性的CD45+EPCs表现出相对不成熟的形态和非典型细胞，与对照组细胞相比有更多的红细胞增多。有限的PEG-IFN治疗期间，CD45+EPCs与免疫耐受和HBsAg清除减少相关。通过转化生长因子β(TGF-β)部分抑制非特异性T细胞活化和HBV特异性CD8+T细胞，可以抑制CD45+EPCs的作用。RNA-seq显示，CHB患者的CD45+EPCs与脐血中的CD45-EPCs和CD45+EPCs具有不同的基因表达谱。值得注意的是，CHB患者的CD45+EPCs高表达淋巴细胞激活基因3(LAG3)，这是一种免疫检查点分子，被定义为LAG3+EPCs。LAG3+EPCs通过LAG3抑制抗原呈递细胞的功能，这是LAG3+EPCs抑制HBV特异性CD8+T细胞的另一个机制。抗-LAG3和抗-TGF-β联合治疗在AAV/HBV小鼠模型中在PEG-IFN治疗期间降低了血清HBeAg、HBV DNA水平和HBsAg水平，以及肝细胞中的HBsAg表达。结论：LAG3+EPCs通过LAG3和TGF-β抑制PEG-IFN治疗诱导的HBsAg清除的有效性。抗-LAG3、抗-TGF-β和PEG-IFN联合治疗可能促进HBV清除。版权所有©2023 Elsevier B.V.发表。

HBsAg seroclearance, the ideal aim of anti-hepatitis B virus (HBV) treatment, cannot be achieved easily. Anemia is another common issue for chronic hepatitis B (CHB) patients, which leads to elevation of erythroid progenitor cells (EPCs) and immune suppression in cancer. This study investigated the role of EPCs in HBsAg seroclearance following PEGylated interferon-α (PEG-IFN) treatment. CD45+EPC accumulation in CHB patients and an AAV/HBV mice model was found in the circulation and liver by flow cytometry and immunofluorescence tests. Wright-Giemsa staining showed that these pathological CD45+EPCs presented elevated erythroid cells with relative immature morphologies and atypical cells compared with the control cells. CD45+EPCs were associated with immune tolerance and decreased HBsAg seroclearance during finite PEG-IFN treatment. CD45+EPCs suppressed antigen non-specific T cell activation and HBV-specific CD8+T cells, partially through transforming growth factor β (TGF-β). RNA-seq revealed that CD45+EPCs in patients with CHB presented a distinct gene expression profile compared with CD45-EPCs and CD45+EPCs from cord blood. Notably, CD45+EPCs from patients with CHB expressed high level of Lymphocyte-activation gene 3 (LAG3), an immune checkpoint molecule, and were then defined as LAG3+EPCs. LAG3+EPCs diminished the function of antigen presenting cells through LAG3, which was another mechanism by which LAG3+EPCs' suppressed HBV-specific CD8+T cells. Anti-LAG3 and anti-TGF-β combination treatment decreased serum HBeAg, HBV DNA levels and HBsAg level, as well as HBsAg-expression in hepatocytes during PEG-IFN treatment in the AAV/HBV mice model. Conclusions: LAG3+EPCs inhibited the efficacy of PEG-IFN treatment on HBsAg seroclearance induced by LAG3 and TGF-β. Anti-LAG3, anti-TGF-β and PEG-IFN combination treatment might facilitate HBV clearance.Copyright © 2023. Published by Elsevier B.V.