Figure 3

Distribution of classically activated (M1) and alternatively activated (M2) phenotype macrophages in the injured spinal cord at 3 days after MR16-1 treatment. A common finding in the MR16-1-treated group was (C, D) a focal injury site with centralized presence of CD11b-positive cells, whereas (A, B) in the rat IgG control group, there was a larger injury site with cephalic and distal expansion of CD11b-positive cells. (E, F) Inducible nitric oxide synthase (iNOS)-positive cells were distributed over the same CD11b-positive area in the rat IgG control group, whereas a weaker reaction to iNOS was seen in (G, H) the MR16-1-treated group. (K, L) Arginase 1-positive cells were localized more specifically to the injury site in the MR16-1-treated group, whereas arginase 1-positive cells were rare in (I, J) the rat IgG control group. (A-D) CD11b conjugated to Alexa fluor 568 (red); E-H) iNOS conjugated to Alexa fluor 488 (green);(I-L) arginase 1 conjugated to Alexa fluor 488 (green); (A-L) DAPI used for nuclear counterstaining (blue). Scale bar: (A, C, E, G, I, K) 200 μm,(B, D, F, H, J, L) 500 μm