Figure 4

Inflammatory cell subtypes. Double labeling of ED1 (Alexa 488, green) and Iba1 (CY3, red) in the contralateral brain (A) and at the lesion site at 1 dpi (B) and 14 dpi (C). On the contralateral side (A), only resting microglia were stained with ramified thin processes and weak Iba1 immunoreactivity. During the edema formation phase (1 dpi, B), many round cells with both ED1 and Iba1 immunopositivity (arrows) were found around vessels (**) and were thought to be infiltrating macrophages, while some could also represent amoeboid microglia with a fully activated profile. At the periphery of the lesion, some activated microglia Iba + but ED1 - could also be observed (arrowheads). During the edema resolution phase (14 dpi, C), most cells were Iba1 + but ED1 - and showed highly branched processes corresponding to activated microglia.