Fig. 6From: An advanced glioma cell invasion assay based on organotypic brain slice culturesMultiple applications of the ex vivo invasion assay. Representative confocal images, scale bars 100 μm, image quality was optimized by adjustment of brightness, contrast and gamma. a-c Brain slices of genetically modified mice as a tool to modulate the microenvironment. Human glioma cell line LN319 implanted in a wild-type and b knockout brain slices. The deletion of a specific cell surface protein in the microenvironment significantly inhibits tumor cell invasion as quantified in (c). Error bars represent 95% confidence interval, (A) n = 7; (B) n = 5; **p < 0.001, Welch’s t-test. d Co-implantation of different cell types. Reactive astrocytes (pseudocolored in green, DiI labeled) and the murine glioma cell line SMA560 (red, DiD labeled) were co-cultured in a ratio of 3:2 as heterotypic multicellular spheroids and implanted in a wild-type brain slice. e-i The ex vivo invasion assay as a tool to identify invasion modulating compounds. 500 SMA560 glioblastoma cells were seeded per well to induce spheroid growth. 18 h prior to implantation, spheroids or brain slices were treated with 1 μM jasplakinolide. 24 h after implantation, brain slices were fixed and imaged by confocal microscopy. In contrast to e the highly invasive control-treated SMA560, f the treatment of the tumor cells or g brain slices with jasplakinolide significantly reduced their ability to invade without inducing cell death as examined by trypan blue staining (i). h Quantification of invasion. Error bars show 95% confidence interval, e n = 12; f, g n = 7; i n = 3; **p < 0.001; ***p ≤ 0.0001; Welch’s t-test, p-values Bonferroni correctedBack to article page