Immune checkpoint inhibitors are becoming a cornerstone of cancer immunotherapy as a result of their clinical success in relieving immune suppression and driving durable antitumor T cell responses in certain subsets of patients. Unfortunately, checkpoint inhibition is also associated with treatment-related toxicities that result in a myriad of side effects, ranging from mild and manageable to severe and debilitating. In this issue of the JCI, Das and colleagues report an association between early therapy-induced changes in circulating B cells and an increased risk of high-grade immune-related adverse events (IRAEs) in patients treated with checkpoint inhibitors that target cytotoxic T lymphocyte–associated antigen-4 (CTLA4) and programmed cell death protein 1 (PD1). These findings identify potential predictive biomarkers for high-grade IRAEs that may be leveraged to improve patient monitoring and may prompt new treatment strategies to prevent IRAEs.

免疫检查点抑制剂由于其在某些患者亚组中缓解免疫抑制和驱动持久的抗肿瘤T细胞反应的临床成功，正成为癌症免疫治疗的基石。不幸的是，检查点抑制也与治疗相关的毒性有关，导致无数的副作用，从轻度，可控制到严重和使人衰弱。在本期JCI中，Das及其同事报告了早期治疗引起的循环B细胞变化与以细胞毒性T淋巴细胞为靶点的检查点抑制剂治疗的患者发生高级别免疫相关不良事件（IRAE）的风险之间的相关性–相关抗原4（CTLA4）和程序性细胞死亡蛋白1（PD1）。