*5.6. Histology of Spinal Cord to Inflammatory Infiltrate Determination (Hematoxylin and Eosin Stain)*

To characterize the cellular infiltrate in the spinal cord, histological analysis was performed in EAE animals after CRO or saline treatment. The region comprised between lumbar segments from the spinal cord was removed and fixed in 10% of paraformaldehyde (PFA) solution for 24 h, at room temperature. After the fixation period, the tissues were transferred for a 70% ethyl alcohol solution, dehydrated, embedded in paraffin, and cut into sections of 5 μm thickness. The sections were stained with hematoxylin-eosin (HE). This classical technique in histological diagnosis has two dyes: hematoxylin, which stains all the nuclei of all cells, and eosin, which stains the cytoplasm of all cells [100].
