Fig. 2

Phenotypic analysis of the different macrophage and microglia populations in BFP-MSC and IL13-MSC grafts in the CNS of eGFP⁺ bone marrow chimaeras. a Overview of a BFP-MSC and IL13-MSC graft, showing MHCII-expressing (blue) and Arg1-expressing (red) microglia and macrophages. Scale bars indicate 200 μm. Details of the BFP-MSC and IL13-MSC implant and border are provided, showing graft-infiltrating macrophages (green) in combination with Arg1- (red) and MHCII-expressing (blue) microglia and macrophages. Scale bars indicate 50 μm. The following cell populations can be distinguished: eGFP⁺MHCII⁺Arg1⁻ macrophages (cyan), eGFP⁺MHCII⁻Arg1⁺ macrophages (yellow), eGFP⁺MHCII⁺Arg1⁺ macrophages (white), eGFP⁺MHCII⁻Arg1⁻ macrophages (green), eGFP⁻MHCII⁺Arg1⁻ microglia (blue), eGFP⁻MHCII⁻Arg1⁺ microglia (red), eGFP⁻MHCII⁺Arg1⁺ microglia (magenta). eGFP⁻MHCII⁻Arg1⁻ microglia (black background) cannot be visualised using this setup. Dotted lines delineate the actual implants. The border area is an area extending 85 μm from the implant. b Cell densities of all different cellular phenotypes characterised within the implant site (upper graph) and in the implant border (lower graph) of BFP-MSC and IL13-MSC grafts. Values are given as mean + standard deviation. Significant differences are indicated with one (p value <0.05), two (p value ≤0.01) or three (p value ≤0.001) asterisks. c Pie graphs showing mean representation of each microglia and macrophage phenotype within the BFP-MSC and IL13-MSC graft and border. For the graft site, the fraction of BFP-MSC or IL13-MSC is indicated. For the border, the fraction of other cells is indicated (*neurons, oligodendrocytes and/or astrocytes). The colours of differentially activated microglia and macrophage correspond to those in Fig. 2a