title: Changes in cytokine secretion induced by altered peptide ligands of myelin basic protein peptide 85-99.
abstract: Myelin basic protein (MBP)-specific T cells were isolated directly from peripheral blood by stimulation either with native MBPp85-99 or altered peptide ligands (APLs) in which substitutions of the lysine were made at position 93, a TCR contact residue. We report here that the APL 93A could alter the cytokine profile of some autoreactive MBPp85-99 reactive T cell clones, switching them from a Th0 phenotype secreting high concentrations of IL-4, IL-5, and IFN-gamma into Th2 cells secreting significantly less IFN-gamma. However, in vitro stimulation with the 93A peptide, in some instances, induced T cells that responded better to the native MBPp85-99 peptide. Functionally, the APL 93A was shown to act as an antagonist for IFN-gamma secretion. Based on TCR sequencing and single cell cloning, this alteration in cytokine profile was determined to be the result of the differential activation of individual T cell clones. We discuss the implications of these data for the strength of signal model of T cell activation.
authors.affiliation: Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA.
authors.forename: L J
authors.initials: LJ
authors.lastname: Ausubel
authors.forename: J I
authors.initials: JI
authors.lastname: Krieger
authors.forename: D A
authors.initials: DA
authors.lastname: Hafler
mesh_terms: D001327:Autoimmune Diseases / Q000097:blood / Q000276:immunology*; D002454:Cell Differentiation / Q000187:drug effects; D002460:Cell Line; D002999:Clone Cells; D015329:Gene Rearrangement, T-Lymphocyte; D006801:Humans; D016056:Immunodominant Epitopes / Q000737:chemistry / Q000276:immunology*; D007371:Interferon-gamma / Q000378:metabolism*; D015847:Interleukin-4 / Q000378:metabolism*; D015848:Interleukin-5 / Q000378:metabolism*; D008213:Lymphocyte Activation; D009103:Multiple Sclerosis / Q000097:blood / Q000276:immunology*; D004676:Myelin Basic Protein / Q000737:chemistry / Q000276:immunology*; D010446:Peptide Fragments / Q000737:chemistry / Q000276:immunology* / Q000494:pharmacology; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000235:genetics; D013329:Structure-Activity Relationship; D016176:T-Lymphocyte Subsets / Q000187:drug effects / Q000276:immunology*; D018417:Th1 Cells / Q000378:metabolism; D018418:Th2 Cells / Q000378:metabolism*
chemical_list: D016056:Immunodominant Epitopes; D015848:Interleukin-5; D004676:Myelin Basic Protein; D010446:Peptide Fragments; D016693:Receptors, Antigen, T-Cell, alpha-beta; C107908:myelin basic protein 85-99; D015847:Interleukin-4; D007371:Interferon-gamma