Emerging Infectious Diseases, Duke-NUS Medical School, Singapore.
Genome Institute of Singapore, Agency for Science and Technology (A*STAR), Singapore.
Gastroenterology. 2019 May;156(6):1862-1876.e9. doi: 10.1053/j.gastro.2019.01.251. Epub 2019 Jan 31.
BACKGROUND & AIMS: Hepatocellular carcinoma (HCC) is often associated with hepatitis B virus (HBV) infection. Cells of most HBV-related HCCs contain HBV-DNA fragments that do not encode entire HBV antigens. We investigated whether these integrated HBV-DNA fragments encode epitopes that are recognized by T cells and whether their presence in HCCs can be used to select HBV-specific T-cell receptors (TCRs) for immunotherapy.
HCC cells negative for HBV antigens, based on immunohistochemistry, were analyzed for the presence of HBV messenger RNAs (mRNAs) by real-time polymerase chain reaction, sequencing, and Nanostring approaches. We tested the ability of HBV mRNA-positive HCC cells to generate epitopes that are recognized by T cells using HBV-specific T cells and TCR-like antibodies. We then analyzed HBV gene expression profiles of primary HCCs and metastases from 2 patients with HCC recurrence after liver transplantation. Using the HBV-transcript profiles, we selected, from a library of TCRs previously characterized from patients with self-limited HBV infection, the TCR specific for the HBV epitope encoded by the detected HBV mRNA. Autologous T cells were engineered to express the selected TCRs, through electroporation of mRNA into cells, and these TCR T cells were adoptively transferred to the patients in increasing numbers (1 × 10-10 × 10 TCR+ T cells/kg) weekly for 112 days or 1 year. We monitored patients' liver function, serum levels of cytokines, and standard blood parameters. Antitumor efficacy was assessed based on serum levels of alpha fetoprotein and computed tomography of metastases.
HCC cells that did not express whole HBV antigens contained short HBV mRNAs, which encode epitopes that are recognized by and activate HBV-specific T cells. Autologous T cells engineered to express TCRs specific for epitopes expressed from HBV-DNA in patients' metastases were given to 2 patients without notable adverse events. The cells did not affect liver function over a 1-year period. In 1 patient, 5 of 6 pulmonary metastases decreased in volume during the 1-year period of T-cell administration.
HCC cells contain short segments of integrated HBV-DNA that encodes epitopes that are recognized by and activate T cells. HBV transcriptomes of these cells could be used to engineer T cells for personalized immunotherapy. This approach might be used to treat a wider population of patients with HBV-associated HCC.
肝细胞癌（HCC）常与乙型肝炎病毒（HBV）感染相关。大多数 HBV 相关 HCC 细胞中含有不编码完整 HBV 抗原的 HBV-DNA 片段。我们研究了这些整合的 HBV-DNA 片段是否编码 T 细胞识别的表位，以及它们在 HCC 中的存在是否可用于选择用于免疫治疗的 HBV 特异性 T 细胞受体（TCR）。
基于免疫组织化学，分析乙型肝炎抗原阴性的 HCC 细胞是否存在 HBV 信使 RNA（mRNA），采用实时聚合酶链反应、测序和 Nanostring 方法。我们使用 HBV 特异性 T 细胞和 TCR 样抗体测试 HBV mRNA 阳性 HCC 细胞生成 T 细胞识别的表位的能力。然后，我们分析了 2 例 HCC 患者肝移植后复发的 HCC 及其转移灶的 HBV 基因表达谱。利用 HBV 转录谱，我们从先前从自限性 HBV 感染患者中鉴定的 TCR 文库中选择针对检测到的 HBV mRNA 编码的 HBV 表位的 TCR。通过将 mRNA 电穿孔到细胞中，工程化自体 T 细胞表达所选 TCR，并以递增的数量（1×10-10×10 TCR+T 细胞/kg）每周向患者输注这些 TCR T 细胞，共 112 天或 1 年。我们监测患者的肝功能、血清细胞因子水平和标准血液参数。根据转移灶甲胎蛋白血清水平和计算机断层扫描评估抗肿瘤疗效。
未表达完整 HBV 抗原的 HCC 细胞含有短 HBV mRNA，编码被 HBV 特异性 T 细胞识别和激活的表位。表达患者转移灶中 HBV-DNA 编码的表位特异性 TCR 的工程化自体 T 细胞给予 2 例患者，无明显不良反应。这些细胞在 1 年内不会影响肝功能。在 1 例患者中，在接受 T 细胞治疗的 1 年期间，6 个肺转移灶中有 5 个体积缩小。
HCC 细胞含有短的整合 HBV-DNA 片段，编码被 T 细胞识别和激活的表位。这些细胞的 HBV 转录组可用于工程化 T 细胞进行个性化免疫治疗。这种方法可能用于治疗更广泛的 HBV 相关 HCC 患者。
