Immune niches in brain metastases contain TCF1+ stem-like T cells, are associated with disease control and are modulated by preoperative SRS

We analyzed immune infiltration in 67 brain metastasis (BrM) and found high frequencies of PD1+TCF1+stem-like CD8+T-cells and TCF1-effector-like cells. CD45+ TILS and CD8+ TILS were mixed at a 1:1 ratio from patients with irradiated and unirradiated brain metastases were FACS-purified for every sample. Single-cell suspensions of FACS-purified cells were loaded onto the 10X Genomics Chromium Controller. Library construction was performed using the Chromium Single Cell 5’ Library Construction Kit followed by sequencing on a HiSeq3000.

我们对67例脑转移瘤（brain metastasis, BrM）样本的免疫浸润特征进行分析，发现PD1+TCF1+干细胞样CD8+T细胞与TCF1+效应样T细胞的丰度较高。本研究从接受放疗与未接受放疗的脑转移瘤患者中获取样本，将其中的CD45+肿瘤浸润淋巴细胞（Tumor Infiltrating Lymphocytes, TILS）与CD8+肿瘤浸润淋巴细胞以1:1的比例混合，随后对每个样本均进行荧光激活细胞分选（fluorescence-activated cell sorting, FACS）纯化。将经FACS纯化后的细胞制备为单细胞悬液，加载至10X Genomics Chromium控制器中。使用Chromium单细胞5'端文库构建试剂盒完成文库构建，随后在HiSeq3000测序平台上进行测序。