T cells become licensed in the lung to enter the central nervous system. Odoardi F, Sie C, Streyl K, Ulaganathan VK, Schläger C, Lodygin D, Heckelsmiller K, Nietfeld W, Ellwart J, Klinkert WEF, et al. Nature. 2012 Aug 30; 488(7413):675-9. Epub 2012 Aug 22. PMID: 22914092. Abstract CommentRecommendBookmarkWatch