Lysolecithin injection

Mice were anaesthetized and given preoperative drugs, as described above. Mice underwent a C5 laminectomy and 1 µl of 1% lysolecithin (Sigma-Aldrich) dissolved in 0.9% saline was stereotaxically injected into the dorsal column at a depth of 0.5 mm using a 33-gauge Hamilton syringe. At 5 days post lysolecithin injection, mice underwent a second surgery for intrathecal delivery of CSF or saline at the site of focal demyelination. Following a C4 laminectomy, a 32-gauge Hamilton syringe was inserted underneath the dura mater and 3 µl CSF or saline was injected into the subarachnoid space. Mice were assigned to different treatment groups in a randomized manner. Mice were perfused for histological analyses at 1 week post CSF injection, as described below. A separate cohort of mice for a longer time-course study was perfused at 27 days post CSF injection.