Fig. 1

Analysis of BFP-MSC and IL13-MSC graft remodelling in the CNS of eGFP⁺ bone marrow chimaeras. a Overview of a BFP-MSC and IL13-MSC graft. Green: eGFP fluorescence from bone marrow-derived macrophages indicating infiltration at the graft. Red: GFAP staining indicates astrogliosis around the graft. Scale bars indicate 200 μm. b Detail of the BFP-MSC and IL13-MSC graft. White: TOPRO-3 marking all nuclei. Green: eGFP fluorescence from graft-infiltrating macrophages (arrows). eGFP⁻ nuclei (arrowheads) are grafted MSC or (few) graft-infiltrating microglia. Scale bars indicate 50 μm. Insets show BFP fluorescence (blue) or no fluorescence (black) from grafted BFP-MSC or IL13-MSC (arrowheads). Green: eGFP fluorescence from graft-infiltrating macrophages (arrows). Scale bars indicate 20 μm. c Overview of a BFP-MSC and IL13-MSC graft. Green: eGFP fluorescence from graft-infiltrating macrophages. Red: Iba1 staining marks both eGFP⁻ microglia and eGFP⁺ macrophages. Scale bars indicate 200 μm. Details of the BFP-MSC and IL13-MSC implant and border show Iba1⁺eGFP⁺ peripheral macrophages mainly within the implant (arrows) and Iba1⁺eGFP⁻ microglia mainly within the border (arrowheads). Scale bars indicate 50 μm. d Overview of a BFP-MSC and IL13-MSC graft. Green: eGFP fluorescence from graft-infiltrating macrophages. Red: MHCII-expressing eGFP⁻ brain-resident microglia and eGFP⁺ peripheral macrophages. Scale bars indicate 200 μm. Details of the BFP-MSC and IL13-MSC implant and border are provided, showing activated MHCII⁺eGFP⁺ macrophages (arrows) and activated MHCII⁺eGFP⁻ microglia (arrowheads). Scale bars indicate 50 μm. e Cell densities of MHCII⁺eGFP⁺ BM-derived macrophages and MHCII⁺eGFP⁻ microglia within the implant and border of BFP-MSC and IL13-MSC grafts. Values are given as mean + standard deviation. Significant differences (p value ≤0.05) are indicated with an asterisk. f Overview of a BFP-MSC and IL13-MSC graft. Green: eGFP fluorescence from graft-infiltrating macrophages. Red: Arg1-expressing eGFP⁻ microglia and eGFP⁺ macrophages. Scale bars indicate 200 μm. Details of the BFP-MSC and IL13-MSC implant and border are provided, showing alternatively activated Arg1⁺eGFP⁺ macrophages (arrows) and Arg1⁺eGFP⁻ microglia (arrowheads). Scale bars indicate 50 μm. g Cell densities of Arg1⁺eGFP⁺ BM-derived macrophages and Arg1⁺eGFP⁻ microglia within the implant and border of BFP-MSC and IL13-MSC grafts. Values are given as mean + standard deviation. Significant differences (p value <0.05) are indicated with an asterisk. h Overview of a BFP-MSC and IL13-MSC graft. Green: eGFP fluorescence from graft-infiltrating macrophages. Red: Ym1-expressing eGFP⁻ microglia and eGFP⁺ macrophages. Scale bars indicate 200 μm. Details of the BFP-MSC and IL13-MSC implant and border are provided, showing Ym1⁺eGFP⁺ BM-derived macrophages (arrows) and Ym1⁺eGFP⁻ microglia (arrowheads). Scale bars indicate 50 μm