A. CCL2−/− mice were injected with collagenase and FL-, K104A-, or K104Stop-CCL2. 1, 3, 7dpi the brains were collected and stained for Iba-1 and iNOS. B. Quantitative data of iNOS (mean pixel intensity) are mean±SD (n=3). C and D. The infiltration of leukocytes and neutrophils was examined using CD45 (C) and Ly6G (D) immunostaining, respectively, at 1, 3, 7dpi. Data are mean±SD (n=4). E. Degenerating neurons were visualized using FluoroJade C on days 1 and 7dpi and quantified. Data are mean±SD (n=3). F. Neurological scores were evaluated at 1, 3, and 7dpi. Values are mean±SD. The animal numbers for CCL2−/− mice infused with FL, K104A, and K104Stop-CCL2 at 1, 3, 7dpi were 8, 8, 3; 9, 6, 4; and 11, 6, 3, respectively.