Fig. 4

Cortical neuron dysfunctions were improved by intranasally delivering CCL5 into CCL5-KO mice. A An illustration of intranasal delivery (i.n.) of recombinant CCL5 into mice. Recombinant CCL5 was administered into mice either (1) 30 min before injury with a single dosage of 300 pg/g or (2) 3 days after injury with 30 pg/g every 2 days until 28 dpi. B Recombinant CCL5 conjugated with Alexa Fluor™ 594 was detected by Alexa Fluor™ 594 (red) and CCL5 specific antibody (green) in mouse cortex. Images of CCL5 at the injury site in the cortex were enlarged on the right B' (Scale bar = 1 mm in B and 100 µm in B’). DAPI labeled the nucleus. C-J A Black dashed line points to the time of brain injury. The Purple dashed line indicates the treatment with CCL5 before the weight drop impact in C-F; the green dashed line and green area indicate the post-treatment with CCL5 from 3 dpi until 28 dpi in G-J. C, G The mNSS score of the CCL5-KO sham group and mice treated with PBS (control) and CCL5 (300 pg/g, single dose) before mTBI or PBS (control) and CCL5 (30 pg/g, every two days) (G: PBS vs Post-L5, p = 0.0418) after mTBI. Motor function of CCL5-KO mice with i.n. PBS or CCL5 was analyzed by Rotarod (D, H) (D: sham vs PBS, p < 0.0001; sham vs Pre-L5, p = 0.0010; PBS vs Pre-L5, p < 0.0001. H: PBS vs Post-L5, p=0.0009), and beam walking (E, I), which was improved in both i.n. CCL5 treated groups. (E: sham vs PBS, p < 0.0001; sham vs Pre-L5, p = 0.0247; PBS vs Pre-L5, p = 0.0038. I: PBS vs Post-L5, p = 0.0006). F, J Sensory function was analyzed by sicker removal test (F: sham vs PBS, p = 0.0028; sham vs Pre-L5, NS; PBS vs Pre-L5, p = 0.0013. J: PBS vs Post-L5 at 4 dpi, p = 0.015, by t-test). The time to remove stickers in CCL5-KO mice was reduced after being treated with CCL5. (n = 4 ~ 5 in C-F; n = 6 in G-J). Data in D-I was analyzed by two-way ANOVA between groups and presented as mean ± SEM