Fig. 2

Analysis of microglial cells shows morphological changes depending on their location towards the tumor tissue. a Coronal section of a TgH(CX3CR1-EGFP) mouse brain implanted with mCherry-GL261 cells at 14 dpi. White boxes indicate the following regions in analysis: 1 − contralateral hemisphere (control non-implanted site); 2 − tumor border and; 3 − tumor core. b Quantitative analysis of microglia cell numbers in regions 1–3, showing an increased number of microglial cells in tumor regions 2 and 3 (border and core, respectively) in comparison with the control region 1 (p < 0,05). In addition the number increase also in the core compared to the border tumor region. c–e Higher magnification of the brain areas 1–3 (white squares) in (a); maximum intensity projections acquired by confocal microscopy. f–h Magnified views of single cells (white boxes in c–e) to show details in cell morphology. In the presence of glioma cells, microglial morphology changes from a ramified (c and f) to an amoeboid shape in the tumors border (d and g) and core (e and h). Scale bars: (a), 500 μm; (c–e), 20 μm; (f–h), 10 μm