中枢神经系统 (CNS) 受累仍然是治疗儿童 B 细胞前体急性淋巴细胞白血病 (BCP-ALL) 的临床障碍。中枢神经系统白血病的疾病机制主要使用二维细胞培养和小鼠模型进行研究。鉴于人类和小鼠中枢神经系统之间细胞特性和结构的差异，寻找互补模型来研究中枢神经系统白血病变得势在必行。在这里，我们提出了首个结合人脑类器官和 BCP-ALL 细胞的 3D 共培养模型。我们注意到，与非 ALL 细胞相比，BCP-ALL 细胞系和患者来源的异种移植 (PDX) 细胞在脑类器官中的植入量明显更高。为了验证类器官共培养和体内小鼠模型之间的可翻译性，我们证实针对 CNS 白血病相关通路（如 CD79a/Igα 或 CXCR4-SDF1）可减少 BCP-ALL 细胞对类器官的侵袭。与非侵袭部分相比，类器官侵入白血病细胞的 RNA 测序和功能验证揭示了类器官侵入细胞中 AP-1 转录因子复合体成员的显着上调。此外，与移植 TCF3::PBX1 PDX 细胞的小鼠脾脏原始细胞相比，我们检测到从 CNS 回收的 ALL-PDX 细胞中 AP-1 通路基因显着富集，证实了 AP-1 信号传导在 CNS 疾病中的作用。因此，我们发现，在 100 名 BCP-ALL 队列中，最初诊断为 CNS 阳性的患者中 AP-1 基因 JUN 的水平显着高于 CNS 阴性病例，以及 CNS 复发病例与非 CNS 复发病例相比-患者。我们的结果表明 CNS 类器官作为研究 CNS 参与的新模型，并确定 AP-1 通路是 BCP-ALL 中 CNS 疾病的关键驱动因素。版权所有 © 2024 美国血液学会。

Central nervous system (CNS) involvement remains a clinical hurdle in treating childhood B-cell precursor acute lymphoblastic leukemia (BCP-ALL). The disease mechanisms of CNS leukemia are primarily investigated using 2D cell culture and mouse models. Given the variations in cellular identity and architecture between the human and murine CNS, it becomes imperative to seek complementary models to study CNS leukemia. Here, we present a first-of-its-kind 3D co-culture model combining human brain organoids and BCP-ALL-cells. We noticed significantly higher engraftment of BCP-ALL cell lines and patient-derived xenograft (PDX) cells in cerebral organoids as compared to non-ALL-cells. To validate translatability between organoid co-culture and in vivo murine models, we confirmed that targeting CNS leukemia relevant pathways like CD79a/Igα or CXCR4-SDF1 reduced the invasion of BCP-ALL-cells into organoids. RNA sequencing and functional validations of organoid-invading leukemia cells compared to the non-invaded fraction revealed significant upregulation of AP-1 transcription factor-complex members in organoid-invading cells. Moreover, we detected a significant enrichment of AP-1 pathway genes in ALL-PDX-cells recovered from the CNS compared to spleen blasts of mice transplanted with TCF3::PBX1+ PDX-cells, substantiating the role of AP-1 signaling in CNS disease. Accordingly, we found significantly higher levels of the AP-1-gene JUN in patients initially diagnosed as CNS-positive compared to CNS-negative cases as well as CNS-relapse vs non-CNS-relapse cases in a cohort of 100 BCP-ALL-patients. Our results suggest CNS-organoids as a novel model to investigate CNS-involvement and identify the AP-1 pathway as a critical driver of CNS-disease in BCP-ALL.Copyright © 2024 American Society of Hematology.