Fig. 1: NK cell markers presence in peri-vascular tumor regions and NK functional inactivation in peripheral blood of GBM patients.

SOX2-positive cells (indicated by magenta arrows) and CD56-positive cells (indicated by white arrows) are found together around SMA-positive vasculature (red arrows) (a, b, e). CD56-positive NK cells were negative for T cell marker CD3 (c). NK markers CD56 and CD16 co-localized in 1 GBM tissue (d). Assessment of immune cell percent within CD45-positive population in peripheral blood of GBM patients and heathy donors was determined by immunolabeling and flow cytometry (f). NK cell function assessment of GBM patient and healthy donor PBMCs (g–i) and NK cells (j–l) after several treatments: IL-2, IL-2 + anti-CD16, IL-2 + anti-CD3/28 and IL-2 + aAJ2 as described in Methods section. NK cell cytotoxicity assay (g, j), ELISA (h, k) and ELISPOT (i, l) for IFN-γ secretion were performed. Cytotoxic ability of patient-derived primary NK cells was tested on UC2 cells. Data are showed for 4 heathy donors (white bars) and 5 GBM patients (gray bars) (f), and for 3 healthy donors and 3 GBM patients (g–l), respectively. Data are presented as means ± SEM, data points represent measurement for each healthy donor/patient Scale bar = 50 µm. TNTC: too numerous to count.