Fu YangHao, Wang TianDuo, Ronald John A
Imaging Laboratories, Department of Medical Biophysics, Robarts Research Institute, University of Western Ontario, London, ON, Canada.
Lawson Health Research Institute, London, ON, Canada.
Front Pharmacol. 2023 Dec 7;14:1304194. doi: 10.3389/fphar.2023.1304194. eCollection 2023.
Cellular immunotherapy has greatly improved cancer treatment in recent years. For instance, chimeric antigen receptor (CAR) T cell therapy has been proven highly effective in treating hematological malignancies, and many CAR cell designs are being explored for solid tumors. However, many questions remain why responses differ across patients and some tumor types are resistant. Improved and relatively inexpensive ways to monitor these cells could provide some answers. Clinically, blood tests are regularly used to monitor these therapies, but blood signals often do not reflect the activity of immune cells within the tumor(s). Here, using the synthetic Notch (synNotch) receptor that tethers antigen binding to customized transgene expression, we linked intratumoral immune-cancer cell communication to a simple secreted reporter blood test. Specifically, we engineered immune cells with a CD19-targeted synNotch receptor and demonstrated that binding to CD19 on cancer cells resulted in the production of secreted embryonic alkaline phosphatase (SEAP) at levels that are readily detected in the blood. Jurkat T cells were engineered via sequential lentiviral transduction of two components: an anti-CD19 synNotch receptor and a synNotch response element encoding SEAP. Co-culture of engineered cells with CD19, but not CD19, Nalm6 cells, resulted in significantly elevated SEAP in media. Nod-scid-gamma (NSG) mice were subcutaneously injected with either CD19 or CD19 Nalm6 cells. Intratumoral injection of engineered T cells (1x10) resulted in significantly elevated blood SEAP activity in mice bearing CD19 tumors (n = 7), but not CD19 tumors (n = 5). Our synNotch reporter system allows for the monitoring of antigen-dependent intratumoral immune-cancer cell interactions through a simple and convenient blood test. Continued development of this system for different target antigens of interest should provide a broadly applicable platform for improved monitoring of many cell-based immunotherapies during their initial development and clinical translation, ultimately improving our understanding of design considerations and patient-specific responses.
近年来，细胞免疫疗法极大地改善了癌症治疗。例如，嵌合抗原受体（CAR）T细胞疗法已被证明在治疗血液系统恶性肿瘤方面非常有效，并且正在探索许多针对实体瘤的CAR细胞设计。然而，关于为何不同患者的反应不同以及某些肿瘤类型具有抗性，仍存在许多问题。改进且相对廉价的监测这些细胞的方法可能会提供一些答案。临床上，血液检测经常用于监测这些疗法，但血液信号往往无法反映肿瘤内免疫细胞的活性。在此，我们使用将抗原结合与定制转基因表达相连接的合成Notch（synNotch）受体，将肿瘤内免疫细胞与癌细胞的通讯与一种简单的分泌型报告物血液检测联系起来。具体而言，我们用靶向CD19的synNotch受体对免疫细胞进行工程改造，并证明与癌细胞上的CD19结合会导致分泌型胚胎碱性磷酸酶（SEAP）的产生，其水平在血液中易于检测到。通过对两个组件进行连续的慢病毒转导来改造Jurkat T细胞：一种抗CD19 synNotch受体和一个编码SEAP的synNotch反应元件。将工程改造的细胞与CD19阳性而非CD19阴性的Nalm6细胞共培养，导致培养基中SEAP显著升高。将Nod-scid-γ（NSG）小鼠皮下注射CD19阳性或CD19阴性的Nalm6细胞。向肿瘤内注射工程改造的T细胞（1×10）导致携带CD19阳性肿瘤的小鼠（n = 7）血液中的SEAP活性显著升高，但携带CD19阴性肿瘤的小鼠（n = 5）则没有。我们的synNotch报告系统允许通过简单便捷的血液检测来监测抗原依赖性肿瘤内免疫细胞与癌细胞的相互作用。针对不同感兴趣的靶抗原持续开发该系统，应能提供一个广泛适用的平台，用于在许多基于细胞的免疫疗法的初始开发和临床转化过程中改进监测，最终增进我们对设计考量和患者特异性反应的理解。
