This indirect modulation of chemotaxis (CCR6–CCL20) and adhesion molecules in the choroid plexus may offer a better approach to treating MS by selectively interfere with the recruitment of pathogenic leukocytes to the CNS while leaving host protective immune mechanisms intact (i.e., by inhibiting certain, but not all, lymphocyte subsets from entering the CNS). The gene discussed is CCR6; the disease is myeloid sarcoma.