Lu I-Na, Müller-Miny Louisa, Krekeler Carolin, Cheung Phyllis Fung-Yi, Antonopoulou Georgia, Jeibmann Astrid, Schulte-Mecklenbeck Andreas, Kerl Kornelius, Call Simon, Reicherts Christian, Bleckmann Annalen, Stelljes Matthias, Lenz Georg, Wiendl Heinz, Zu Hörste Gerd Meyer, Grauer Oliver M
Department of Neurology With Institute of Translational Neurology, University Hospital Münster, Albert-Schweitzer-Campus 1, Bldg A1, Münster, 48149, Germany.
Department of Pediatric Hematology and Oncology, University Children's Hospital Münster, Münster, Germany.
Genome Med. 2025 Jun 30;17(1):71. doi: 10.1186/s13073-025-01498-6.
Immune effector cell-associated neurotoxicity syndrome (ICANS) is a common and potentially life-threatening complication of chimeric antigen receptor (CAR) T cell therapy. The underlying mechanisms of ICANS remain incompletely understood and are unlikely to be explained by cytokine excess alone.
We analyzed paired peripheral blood and cerebrospinal fluid (CSF) samples from CAR T cell-treated patients who developed ICANS (n = 11) within 5-21 days post-infusion. ICANS severity was graded as follows: grade 1 (n = 3), grade 2 (n = 4), grade 3 (n = 1), and grade 4 (n = 3). Control samples were obtained from patients with idiopathic intracranial hypertension, functional neurological disorders, and multiple sclerosis. We employed single-cell RNA sequencing (scRNA-seq) and flow cytometry to profile immune cell populations and performed multi-modal spatial transcriptomics and immunofluorescence on postmortem choroid plexus and brain tissue from a patient with fatal grade 4 ICANS.
We identified a distinct population of proliferating, cytotoxic T cells characterized by CXCR6 expression, enriched in CD4 + CAR T cells and predominantly localized in ICANS CSF. These CXCR6 + T cells were largely absent from control CSF samples. Spatial mapping of postmortem brain tissue revealed widespread infiltration of myeloid cells and a striking spatial association between CXCR6 + T cells and CXCL16-expressing myeloid cells in both the choroid plexus and brain parenchyma. Notably, CSF levels of CXCL16 positively correlated with ICANS severity across the cohort, from grade 1 to grade 4.
Our findings implicate the CXCL16/CXCR6 axis in the recruitment of cytotoxic CAR CD4 + T cells to the central nervous system (CNS) during ICANS. This interaction may be linked to neuroinflammatory processes and severity stratification in ICANS pathogenesis. These results provide a mechanistic rationale for exploring CXCL16/CXCR6 as a potential biomarker and therapeutic target in CAR T cell-associated neurotoxicity.
免疫效应细胞相关神经毒性综合征（ICANS）是嵌合抗原受体（CAR）T细胞疗法常见且可能危及生命的并发症。ICANS的潜在机制仍未完全明确，不太可能仅由细胞因子过量来解释。
我们分析了接受CAR T细胞治疗且在输注后5至21天内发生ICANS的患者（n = 11）的配对外周血和脑脊液（CSF）样本。ICANS严重程度分级如下：1级（n = 3）、2级（n = 4）、3级（n = 1）和4级（n = 3）。对照样本取自特发性颅内高压、功能性神经障碍和多发性硬化症患者。我们采用单细胞RNA测序（scRNA-seq）和流式细胞术对免疫细胞群体进行分析，并对一名死于4级ICANS患者的死后脉络丛和脑组织进行多模态空间转录组学和免疫荧光分析。
我们鉴定出一群以CXCR6表达为特征的增殖性细胞毒性T细胞，在CD4 + CAR T细胞中富集，主要定位于ICANS脑脊液中。对照脑脊液样本中基本不存在这些CXCR6 + T细胞。死后脑组织的空间图谱显示髓样细胞广泛浸润，且在脉络丛和脑实质中CXCR6 + T细胞与表达CXCL16的髓样细胞之间存在显著的空间关联。值得注意的是，在整个队列中，从1级到4级，脑脊液中CXCL16水平与ICANS严重程度呈正相关。
我们的研究结果表明，在ICANS期间，CXCL16/CXCR6轴参与将细胞毒性CAR CD4 + T细胞募集到中枢神经系统（CNS）。这种相互作用可能与ICANS发病机制中的神经炎症过程和严重程度分层有关。这些结果为探索CXCL16/CXCR6作为CAR T细胞相关神经毒性的潜在生物标志物和治疗靶点提供了机制依据。
