title: Alpha-galactosylceramide-driven expansion of human natural killer T cells is inhibited by prednisolone treatment.
abstract: The mechanisms of action of most treatments in the autoimmune disorders are unclear and steroids remain the first-line therapy in these diseases. Natural killer T (NKT) cell activity has been implicated in the autoimmune process but whether steroids act via an affect on NKT cell function, such as antigen-specific proliferative capacity, is unknown. Immune thrombocytopenia (ITP) patients were studied ex vivo for NKT cell expansion in response to the specific NKT cell antigen, alpha-galactosylceramide, before, during or after prednisolone treatment. Prednisolone inhibited antigen-specific NKT cell expansion in ITP patients in remission. Untreated ITP patients also showed reduced NKT cell proliferative capacity, although this was less marked than in treated patients. These results support a role for NKT cells in ITP and aid understanding of the immunosuppressive activities of prednisolone in autoimmune disease.
authors.affiliation: Department of Haematology, Barts and the London, Queen Mary School of Medicine and Dentistry, London, UK. ulrika.johansson@bartsandthelondon.nhs.uk
authors.forename: Ulrika
authors.initials: U
authors.lastname: Johansson
authors.forename: Marion G
authors.initials: MG
authors.lastname: Macey
authors.forename: Deborah
authors.initials: D
authors.lastname: Kenny
authors.forename: Drew
authors.initials: D
authors.lastname: Provan
authors.forename: Adrian C
authors.initials: AC
authors.lastname: Newland
mesh_terms: D000328:Adult; D000893:Anti-Inflammatory Agents / Q000494:pharmacology; D002455:Cell Division / Q000187:drug effects / Q000276:immunology; D002478:Cells, Cultured; D005260:Female; D005699:Galactosylceramides / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D005938:Glucocorticoids / Q000494:pharmacology*; D006801:Humans; D007166:Immunosuppressive Agents / Q000494:pharmacology; D007694:Killer Cells, Natural / Q000187:drug effects* / Q000276:immunology; D008297:Male; D008875:Middle Aged; D011239:Prednisolone / Q000494:pharmacology*; D016553:Purpura, Thrombocytopenic, Idiopathic / Q000188:drug therapy / Q000276:immunology*; D016176:T-Lymphocyte Subsets / Q000276:immunology
chemical_list: D000893:Anti-Inflammatory Agents; D005699:Galactosylceramides; D005938:Glucocorticoids; D007166:Immunosuppressive Agents; D011239:Prednisolone