title: GSM8800498: LB4102_GEX; Homo sapiens; RNA-Seq
library_construction_protocol: Tumor-infiltrating CD45+ immune cell populations were isolated from GBM tumors of patients undergoing surgical resection at the University of California, Los Angeles.  Resected tumor tissue not needed for diagnosis was digested using the Miltenyi Brain Tumor Dissociation kit (Miltenyi Biotec, cat. 130-095-42) and gentleMACS dissociator (Miltenyi Biotec, cat. 130-093-235).  After treatment with Myelin Removal Beads II (Miltenyi Biotec, cat. 130-096-433), cells were labeled with CD45+ microbeads (Miltenyi Biotec, cat. 130-045-801). CD45+ cells were positively selected from the tumor digest with Miltenyi LS columns (Miltenyi Biotec, cat. 130-042-401) and MidiMACS separator (Miltenyi Biotec, cat. 130-042-302) and immediately frozen for batched analysis in Bambanker (Fisher Scientific, cat. 302-14681) and stored in liquid nitrogen. On the day of single-cell library preparation, CD45+ cells collected from GBM patient tumors were thawed, counted, and resuspended in PBS with 0.4% BSA (Gemini, cat. 700-101P-100).  Single-cell library construction was performed by the Technology Center for Genomics and Bioinformatics Core, UCLA, utilizing the Chromium single-cell 5′ and VDJ library construction (10x Genomics), per the manufacturer's protocol.  The constructed single-cell libraries were sequenced on a Novaseq S4 2x100bp flow cell (Illumina).