All these data corroborate the hypothesis that meningeal infiltrates may constitute the main source of CSF intrathecal inflammation [43], a view that has been recently confirmed by a new model of MS-like cortical pathology obtained by injecting lentiviral transfer vectors into the sagittal sulcus of Dark Agouti rats, in order to induce continuous expression of TNF + IFNγ. This evidence concerns the gene IFNG and myeloid sarcoma.