Fig. 5

Antagonizing miR-615-5p in microglia significantly alleviated EAE development. A Mice were divided into three groups: PBS group, AAV-Scramble group, and AAV-miR-615-5p-Sponge group. Two days before immunization, AAVs were injected into mice via the lateral ventricles. After 27 days of immunization, spinal cords, and brains were harvested, and HE, LFB, IF, TEM, qRT-PCR, and WB were performed. B Immunofluorescence staining of Iba1 and GFP and local magnification in each group is shown on the right, and C the number of Iba1⁺GFP⁺ cells per mm². D, E qRT-PCR analysis of miR-615-5p in mouse brain and spinal cords. F Clinical score of EAE mice. The @ symbol represents the comparison between the PBS group and the AAV-miR-615-5p-Sponge group. The # symbol represents the AAV-Scramble group compared with the AAV-miR-615-5p-Sponge group. G The cumulative scores were calculated from day 10 to day 27 p.i. H Spinal cords were assayed for H&E staining, I LFB staining, and J MBP fluorescence staining. The lower rows of (K–M) showed the locally enlarged images of H&E, LFB, and MBP staining in each group. The red circle represents inflammatory cell infiltration in (H). K, L Statistical results of H&E and LFB pathological scores. M MBP⁺ area per mm². Each data point represents the average of 4–6 regions of interest analyzed per section from at least 3 sections per animal with n ≥ 3 mice per group. Spinal cord samples analyzed in the white matter lesion area (B, H, I, J). Typical representative figures show the dorsal cord lesion area of the spinal cord (B, J). All data are represented by mean ± SEM. One-way ANOVA was used to determine P values (C, D, E, G, K, M, L). Two-way ANOVA was used to determine P values (E). @P < 0.05 (day 15-27), #P < 0.05 (day 24–27), *P < 0.05, **P < 0.01, ****P < 0.0001. One representative of three independent experiments is shown. Scale bar = 100 μm (B) and 500 μm (G–I)