Inflammatory diseases in the CNS can be treated or alleviated by the administration of an oligonucleotide in an amount sufficient to reduce the influx of mononuclear cells to the central nervous system by down-regulating the expression of at least one cell surface marker. For example multiple sclerosis can be treated or at least alleviated, by the administration of an oligonucleotide in a dose effective to inhibit or reduce the influx of mononuclear and/or autoaggressive cells to the central nervous system. The oligonucleotide can be used alone, or in combination with other treatment strategies.