Persistence of myelin aberrations in CX3CR1^−/− mice after remyelination. (A) Remyelination was assessed by the histological Black Gold staining in the corpus callosum 1 wk after cuprizone was removed from the diet. These photomicrographs are representative examples of such histological preparations for each group. Black Gold area was quantified in the corpus callosum with a stereological procedure. (B) Representative electron microscopy imaging of myelin aberrations in the corpus callosum of WT and CX3CR1^−/− mice after remyelination. 5 wk after a cuprizone-supplemented diet, mice were killed 1 wk after normal feeding. (C) Stereologic assessment of the number of axons with aberrant myelin patterns. Presented are the means of at least three fields of view at 1900X per each animal. On average, 152 axons were counted per field of view. One representative experiment out of two is shown. n = 4–6 mice/group. *, P = 0.027; ***, P = 0.0010; ****, P < 0.0001. Bars: (A) 100 µm; (B) 500 nm (left); 2 µm (right).