State Key Laboratory of Proteomics, National Center for Protein Sciences, Beijing, Beijing Proteome Research Center, Beijing Institute of Lifeomics, Beijing, P.R. China; School of Life Sciences, Peking University, Beijing, P.R. China.
State Key Laboratory of Proteomics, National Center for Protein Sciences, Beijing, Beijing Proteome Research Center, Beijing Institute of Lifeomics, Beijing, P.R. China.
Gastroenterology. 2018 Jun;154(8):2222-2236. doi: 10.1053/j.gastro.2018.03.021. Epub 2018 Mar 12.
BACKGROUND & AIMS: Production of neutralizing antibodies against hepatitis B surface antigen (HBsAg) is dysregulated in patients with persistent hepatitis B virus (HBV) infection. We investigated mechanisms by which this immune response to the virus is disrupted and whether it can be restored to promote clearance of HBV.
Immune-competent C57BL/6N and C57BL/6J, as well as mice deficient in follicular helper T cells (Tfh-cell-deficient), B cells, or Foxp3 T-regulatory cells (Treg cell deficient), were given hydrodynamic injections of pAAV/HBV1.2 plasmids. Some mice were given injections of sorted Tfh cells, pan-B cells, Treg cells, or a blocking antibody against CTLA4. Production of antibodies against HBsAg and clearance of HBV were assessed by flow cytometry, enzyme-linked immunosorbent assay, polymerase chain reaction, and immunohistochemical analyses. We obtained blood samples from patients with HBV infection and isolated Treg cells. We measured the ability of Treg cells to suppress production of interleukin 21 (IL21) in CD4 T cells.
Immune-competent C57BL/6N and C57BL/6J mice transfected with the plasmid encoding HBV had features of viral clearance and viral persistence observed in humans. A Tfh-cell response to HBsAg was required for clearance of HBV and was suppressed by Treg cells in mice with persistent HBV infection. Depletion of Treg cells or inhibition of Treg-cell function (with blocking antibody against CTLA4) restored the Tfh-cell response against HBsAg and clearance of HBV in mice. Impaired Tfh-cell response to HBsAg was observed in blood from patients with chronic HBV infection, responsiveness was restored by depletion of Treg cells or blocking antibody against CTLA4.
In studies of HBV-infected mice and blood from patients with chronic HBV infection, we found a Tfh-cell response to HBsAg of to be required for HBV clearance, and that this response was blocked by Treg cells. Inhibiting Treg-cell activity using neutralizing antibody against CTLA4 restored the ability of Tfh cells to clear HBV infection; this approach might be developed for treatment of patients with chronic HBV infection.
针对乙型肝炎表面抗原（HBsAg）的中和抗体的产生在慢性乙型肝炎病毒（HBV）感染患者中失调。我们研究了破坏这种针对病毒的免疫反应的机制，以及是否可以恢复这种免疫反应以促进 HBV 的清除。
用 pAAV/HBV1.2 质粒对免疫功能正常的 C57BL/6N 和 C57BL/6J 以及滤泡辅助 T 细胞（Tfh 细胞缺陷）、B 细胞或 Foxp3 T 调节细胞（Treg 细胞缺陷）缺陷的小鼠进行水力注射。一些小鼠接受了分选的 Tfh 细胞、泛 B 细胞、Treg 细胞或 CTLA4 阻断抗体的注射。通过流式细胞术、酶联免疫吸附试验、聚合酶链反应和免疫组织化学分析评估针对 HBsAg 的抗体产生和 HBV 的清除。我们从 HBV 感染患者中获得血液样本并分离了 Treg 细胞。我们测量了 Treg 细胞抑制 CD4 T 细胞产生白细胞介素 21（IL21）的能力。
转染 HBV 质粒的免疫功能正常的 C57BL/6N 和 C57BL/6J 小鼠具有人类中观察到的清除 HBV 和持续性 HBV 感染的特征。Tfh 细胞对 HBsAg 的反应是清除 HBV 所必需的，并且在持续性 HBV 感染的小鼠中被 Treg 细胞抑制。Treg 细胞耗竭或 Treg 细胞功能抑制（用 CTLA4 阻断抗体）恢复了小鼠针对 HBsAg 的 Tfh 细胞反应和 HBV 的清除。在慢性 HBV 感染患者的血液中观察到对 HBsAg 的 Tfh 细胞反应受损，通过 Treg 细胞耗竭或 CTLA4 阻断抗体恢复了对 HBsAg 的反应。
在 HBV 感染小鼠和慢性 HBV 感染患者的血液研究中，我们发现针对 HBsAg 的 Tfh 细胞反应是清除 HBV 所必需的，并且该反应被 Treg 细胞阻断。使用 CTLA4 中和抗体抑制 Treg 细胞活性恢复了 Tfh 细胞清除 HBV 感染的能力；这种方法可能被开发用于治疗慢性 HBV 感染患者。
