IBA-1 and Mac-2 immunoreactivity following TBI. Representative photomicrographs showing IBA-1-ir microglia scattered throughout the white matter in sham (A) and 8-day post-TBI (B) animals. Semi-quantitative analysis shows statistically significant increases in the density of IBA-1-ir microglia 1, 8 and 14 days following injury (C). *,p < 0.0001; **, p < 0.006 vs. sham. Representative photomicrographs showing pattern of galectin-3/Mac-2 labelling in uninjured (D) and injured 8 days post-TBI (E) animals. Semi-quantitative evaluation of the density of labeled cells confirms that following TBI, there is a significant increase in labelling (F) (*, p < 0.0001 vs. sham). There is also a significant difference in the density of labelling between naïve and sham animals at all time points (#, p < 0.0002 vs. sham). Bar = 100 μm in A-E. Representative photomicrographs illustrating microglia labeled for galectin-3/Mac-2 (G) or IBA-1 (H), and a pattern of co-localization (I). All galectin-3/Mac-2-labeled cells are immunoreactive for IBA-1, confirming that galectin-3/Mac-2-ir cells are microglia (arrowhead in panel G). However, there are IBA-1-ir cells that are not immunoreactive for galectin-3/Mac-2 (arrows in panels H and I), suggesting that IBA-1 labels a broader population of microglia. Bar = 20 μm in G-I.