CCL2⁺ cells are GFAP⁺ astrocytes in human glioma.

<p>(A) Confocal images show co-localization of CCL2-expressing cells (red) with GFAP (green) in glioma. Insert shows a detail of a single CCL2-expressing cell (red) co-localizing with GFAP (green) and counterstained with DAPI (blue). Scale bar: 30 µm. (B) Areas of infiltration of CD3⁺ T-cells (green) coincide with the areas of CCL2-expressing cells (red) in glioma. Confocal images show a tumorigenic area, infiltrated with CD3⁺ T-cells (green) in an area with numerous CCL2-expressing cells (red). The immunostaining was combined with a counterstaining with DAPI to detect the nucleus (blue). Scale bar: 50 µm. (C) Examples of characteristic CD3 infiltration in samples of glioma. CD3⁺ T-cells can be observed grouped in BVs (BV, limited by broken red line in 1 and 3) but also infiltrated in the parenchyma (2, 4, blue insert magnified in 5). (D) CCL2 expression correlates with the infiltration of T-cells in the tumor areas. The quantification in serial sections of the number of T-cells, either infiltrated or located in the BV lumen, revealed that the level of infiltration of CD3⁺ T-cells in the parenchyma (green) is positively correlated with the level of CCL2 expression (BV; BV lumen).