儿童高级别胶质瘤 (PHGG) 是一种侵袭性脑肿瘤，根据亚型不同，五年生存率从低于 2% 到 20% 不等。 PHGG 因患者而异，且瘤内异质性不同，这给治疗设计带来了挑战。我们假设异质性的发生是因为 PHGG 以不同的比例包含多种不同的肿瘤和免疫细胞类型，每种类型都可能影响肿瘤特征。我们从我们机构的儿科脑肿瘤库中获得了 19 个 PHGG 样本。我们使用单细胞 RNA 测序 (scRNA-Seq) 在单细胞水平构建了全面的转录组数据集，鉴定了已知的神经胶质细胞和免疫细胞类型，并进行了差异基因表达和基因集富集分析。我们进行了多通道免疫荧光 (IF) 染色来确认转录组结果。我们的 PHGG 样本包括三种主要的预测肿瘤细胞类型：星形胶质细胞、少突胶质细胞祖细胞 (OPC) 和间充质样细胞 (Mes)。这些细胞类型在基因表达谱、通路富集和间充质特征方面有所不同。我们确定了富含间充质和炎症基因表达的巨噬细胞群作为间充质肿瘤特征的可能来源。我们发现了 T 细胞耗竭和抑制的证据。PHGG 包含多种不同的增殖肿瘤细胞类型。小胶质细胞衍生的巨噬细胞可能驱动 PHGG 中的间充质基因表达。预测的 Mes 肿瘤细胞群可能源自 OPC。不同的肿瘤细胞群依赖于不同的致癌途径，因此对治疗的反应可能会有所不同。© 作者 2023。由牛津大学出版社代表神经肿瘤学会出版。版权所有。如需权限，请发送电子邮件至：journals.permissions@oup.com。

Pediatric high-grade gliomas (PHGG) are aggressive brain tumors with five-year survival rates ranging from less than 2% to 20% depending upon subtype. PHGG presents differently from patient to patient and is intratumorally heterogeneous, posing challenges in designing therapies. We hypothesized that heterogeneity occurs because PHGG comprises multiple distinct tumor and immune cell types in varying proportions, each of which may influence tumor characteristics.We obtained 19 PHGG samples from our institution's pediatric brain tumor bank. We constructed a comprehensive transcriptomic dataset at the single-cell level using single-cell RNA-Seq (scRNA-Seq), identified known glial and immune cell types, and performed differential gene expression and gene set enrichment analysis. We conducted multi-channel immunofluorescence (IF) staining to confirm the transcriptomic results.Our PHGG samples included three principal predicted tumor cell types: astrocytes, oligodendrocyte progenitors (OPCs), and mesenchymal-like cells (Mes). These cell types differed in their gene expression profiles, pathway enrichment, and mesenchymal character. We identified a macrophage population enriched in mesenchymal and inflammatory gene expression as a possible source of mesenchymal tumor characteristics. We found evidence of T-cell exhaustion and suppression.PHGG comprises multiple distinct proliferating tumor cell types. Microglia-derived macrophages may drive mesenchymal gene expression in PHGG. The predicted Mes tumor cell population likely derives from OPCs. The variable tumor cell populations rely on different oncogenic pathways and are thus likely to vary in their responses to therapy.© The Author(s) 2023. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.