PO.TB10.19 · 肿瘤生物学
LAMP3+ 迁移性树突状细胞在非霍奇金淋巴瘤中建立免疫可及的肿瘤微环境
LAMP3+ migratory dendritic cells establish immune-accessible tumor microenvironment in non-Hodgkin lymphoma
作者与单位 Authors & Affiliations
摘要 Abstract
中文摘要
有效的抗肿瘤免疫需要具有功能的肿瘤浸润淋巴细胞（TILs）迁移进入肿瘤巢、识别肿瘤抗原，并在抑制性肿瘤微环境（TME）中发挥效应功能。与免疫可及的“热”肿瘤相比，免疫不可及的“冷”肿瘤缺乏免疫细胞浸润并对免疫治疗产生抵抗。肿瘤中并存的病毒感染进一步塑造 TME 异质性，促成一种限制抗肿瘤免疫的免疫调节状态。我们旨在剖析 TME 中的空间异质性，以识别非霍奇金淋巴瘤（NHL）中决定 T 细胞浸润和效应功能、并构成热肿瘤与冷肿瘤区别的免疫决定因素。我们使用来自 12 例 NHL 患者（6 例 HIV+ 和 6 例 HIV−，包括 3 例 ABC-DLBCL、7 例 GCB-DLBCL 和 2 例 EBV+ 伯基特淋巴瘤）伴有和不伴有病毒感染（EBV 和 HIV）的治疗前速冻肿瘤，以及来自 17 例无 NHL 供者（9 例 HIV+ 和 8 例 HIV−）的淋巴结，进行了单细胞多组学（同一细胞核中配对的 ATAC-seq 和 RNA-seq），并分析了 415,548 个细胞，其中包括 127,455 个癌细胞和 40,730 个 TILs。从匹配的组织中，我们对 69 个组织切片进行了空间转录组学（10x Xenium 免疫肿瘤学面板，含 100 个自定义探针，包括 HIV 和 EBV 特异性探针）。在 HIV+ 和 HIV− 的 NHL 肿瘤切片中，我们发现具有高 I 型干扰素刺激基因（ISG）表达的空间离散肿瘤区域，其与局部 EBV 或 HIV 表达无相关性，从而排除了病毒诱导的 I 型 IFN 反应作为 ISG 梯度主要驱动因素的可能。单细胞多组学与空间转录组学联合分析显示，LAMP3+ 迁移性树突状细胞（LAMP3+ mDCs）建立了离散的 ISG 高表达生态位，其特征为成纤维网状细胞的 CXCL9 和 CXCL10 表达、CXCR3+ 细胞毒性 CD8 T 细胞浸润增加，以及上调 MHC I 类和 II 类且增殖减少的 ISG 高表达癌细胞。相反，在没有 LAMP3+ mDCs 的肿瘤巢中，TIL 浸润极少，癌细胞不表达 ISG，MHC I 和 MHC II 表达降低，并维持增殖能力。使用 NicheNet（单细胞）和 CellNEST（空间转录组学）进行的配体-受体分析显示，LAMP3+ mDCs 既通过 IL-15 反式呈递支持 TIL 的细胞毒性，又通过 PD-L1-PD-1 结合促成 TIL 耗竭。除 TIL 耗竭外，基因调控网络显示，HIV 诱导的抑制性 TME 由 MAF 塑造，其驱动 CD4+ T 细胞向 I 型调节性（Tr1）表型（MAF、IKZF2、TIGIT、CTLA4、IL2RB 和 IL12RB2）发展。总体而言，我们识别出由 LAMP3+ mDC 界定的生态位，其驱动 I 型 IFN 梯度并协调免疫效应细胞的招募与功能。我们的研究提名 LAMP3+ mDCs 作为免疫治疗靶点，以促进 TIL 向冷肿瘤的迁移并增强抗肿瘤免疫。
查看英文原文 English abstract
Effective anti-tumor immunity requires functional tumor infiltrating lymphocytes (TILs) to migrate into the tumor nest, recognize tumor antigens, and exert effector function despite suppressive tumor microenvironment (TME). Compared to immune-accessible “hot” tumors, immune-inaccessible “cold” tumors lack immune cell infiltration and resist immunotherapy. Concomitant viral infections in the tumor further shape TME heterogeneity, promoting an immunoregulatory state that limits anti-tumor immunity. We aim to dissect spatial heterogeneity in the TME to identify immune determinants of T cell infiltration and effector function that underlie hot versus cold tumors in non-Hodgkin lymphoma (NHL). Using pre-treatment snap-frozen tumors with and without viral infections (EBV and HIV) from 12 NHL patients (6 HIV+ and 6 HIV−, including 3 ABC-DLBCL, 7 GCB-DLBCL, and 2 EBV+ Burkitt lymphoma) and lymph nodes from 17 donor without NHL (9 HIV+ and 8 HIV−), we performed single-cell multi-omics (paired ATAC-seq and RNA-seq in the same nucleus) and profiled 415,548 cells, including 127,455 cancer cells and 40,730 TILs. From matched tissues, we performed spatial transcriptomics (10x Xenium immuno-oncology panel with 100 custom probes, including HIV- and EBV-specific probes) in 69 tissue sections. Across HIV+ and HIV− NHL tumor sections, we found spatially discrete tumor regions with high type I Interferon stimulated gene (ISG) expression that did not correlate with local EBV or HIV expression, excluding viral-induced type I IFN responses as the primary drivers of ISG gradients. Joint single-cell multi-omics and spatial transcriptomics profiling revealed that LAMP3+ migratory dendritic cells (LAMP3+ mDCs) established discrete ISG-high niches characterized by CXCL9 and CXCL10 expression from fibroblastic reticular cells, increased infiltration of CXCR3+ cytotoxic CD8 T cells, and ISG-high cancer cells that upregulated MHC class I and II with reduced proliferation. In contrast, in tumor nests without LAMP3+ mDCs, TIL infiltration was minimal, and cancer cells did not express ISG, had decreased MHC I and MHC II expression, and maintained proliferation capacity. Ligand-receptor analysis with NicheNet (single-cell) and CellNEST (spatial transcriptomics) revealed that LAMP3+ mDCs supported both TIL cytotoxicity via IL-15 trans-presentation and TIL exhaustion through PD-L1-PD-1 engagement. In addition to TIL exhaustion, gene-regulatory networks revealed that HIV-induced suppressive TME was shaped by MAF, which drove CD4+ T cells towards a type I regulatory (Tr1) phenotype ( MAF , IKZF2 , TIGIT , CTLA4 , IL2RB , and IL12RB2 ). Overall, we identified LAMP3+ mDC-defined niches that drives type I IFN gradients and coordinates immune effector recruitment and function. Our study nominates LAMP3+ mDCs as immunotherapy targets to promote TIL migration into cold tumors and enhance anti-tumor immunity.
利益披露 Disclosure
Y. Wei, None..
D. A. Braun, None..
Y. Ho, None.