Ultrasonic Aspiration-Acquired Glioblastoma Tissue Preserves Lymphocyte Phenotype and Viability, Supporting Its Use for Immunological Studies

Background and Objective: Access to high-quality patient-derived brain tumor tissues is instrumental for translational neuro-oncology research. Glioblastoma tumor material resected by ultrasonic aspiration (UA) during surgery offers an abundant source of material; however, it is generally not used for research experiments. We hypothesize that UA-derived tumor tissue represents a source of tissue that accurately reflects the immune infiltrates of glioblastomas. Methods: In this study, we have utilized UA-derived tissue and performed a head-to-head comparison with paired resection tissue from the vital tumor core of the same patient. A combination of 16 fluorochrome-conjugated antibodies was designed to identify tumor-infiltrating T, B, and NK lymphocytes and characterize the TILs by spectral flow cytometry. Furthermore, a 5-plex panel was designed to spatially characterize the T cells, macrophages, and tumor cells on the paired UA and resection tissues. Results: UA-obtained cells exhibited a comparable yield and viability, as well as an abundance of tumor-infiltrating T, B, and NK lymphocytes compared to resection sample-derived cells. Importantly, we observed that there is a high concordance with respect to expression intensities of immune checkpoints by T cells in both types of tissue samples. Conclusions: These findings underscore the feasibility and reliability of utilizing the immune infiltrates from ultrasonic aspiration-acquired glioblastoma tissue.