title: Reply to "'Thinking without thinking' about natalizumab and PML".
authors.forename: Sidney
authors.initials: S
authors.lastname: Houff
authors.forename: Joseph R
authors.initials: JR
authors.lastname: Berger
mesh_terms: D000911:Antibodies, Monoclonal / Q000009:adverse effects*; D061067:Antibodies, Monoclonal, Humanized; D000917:Antibody Formation / Q000187:drug effects / Q000276:immunology; D001402:B-Lymphocytes / Q000187:drug effects* / Q000276:immunology; D001921:Brain / Q000187:drug effects / Q000276:immunology / Q000821:virology; D049109:Cell Proliferation / Q000187:drug effects; D006801:Humans; D007111:Immunity, Cellular / Q000187:drug effects / Q000276:immunology; D007165:Immunosuppression Therapy / Q000009:adverse effects; D007577:JC Virus / Q000187:drug effects* / Q000276:immunology; D007968:Leukoencephalopathy, Progressive Multifocal / Q000139:chemically induced* / Q000276:immunology / Q000821:virology*; D009103:Multiple Sclerosis / Q000188:drug therapy* / Q000276:immunology / Q000503:physiopathology; D000069442:Natalizumab; D013601:T-Lymphocytes / Q000187:drug effects / Q000276:immunology
chemical_list: D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D000069442:Natalizumab