title: A novel single chain I-A(b) molecule can stimulate and stain antigen-specific T cells.
abstract: Multimers of soluble major histocompatibility complex class I and II molecules have proven to be useful reagents in quantifying and following specific T cell populations. This study describes the design, generation, and characterization of a novel, single chain I-A(b) molecule which utilizes a unique linker derived from the murine invariant chain. A fragment of the invariant chain, residues 58-85, binds to a region proximal to the class II peptide binding groove and stabilizes occupancy of the class II invariant chain-associated peptide. We have utilized this fragment, replacing CLIP with the Ealpha peptide sequence, to lock the attached peptide into the class II binding groove. The single chain I-A(b) molecule was recognized by a panel of conformation-sensitive, I-A(b)-specific, monoclonal antibodies. Membrane-bound and soluble forms of the single chain I-A(b) stimulated an antigen-specific T cell hybridoma, and tetramers made from soluble monomers stained these cells. The unique features of this molecule may be useful in the design of recombinant T cell receptor ligands containing peptides with low affinity for MHC.
authors.affiliation: Department of Pathology and Laboratory of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA.
authors.forename: Wesley P
authors.initials: WP
authors.lastname: Thayer
authors.forename: Chinh T
authors.initials: CT
authors.lastname: Dao
authors.forename: Leszek
authors.initials: L
authors.lastname: Ignatowicz
authors.forename: Peter E
authors.initials: PE
authors.lastname: Jensen
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000944:Antigens, Differentiation, B-Lymphocyte / Q000235:genetics; D001483:Base Sequence; D019556:COS Cells; D002460:Cell Line; D002462:Cell Membrane / Q000276:immunology; D002522:Chlorocebus aethiops; D005802:Genes, MHC Class II; D005813:Genes, Synthetic; D000949:Histocompatibility Antigens Class II / Q000235:genetics / Q000276:immunology*; D006801:Humans; D007074:Immunoglobulin G / Q000235:genetics / Q000276:immunology; D007518:Isoantibodies / Q000276:immunology; D008213:Lymphocyte Activation; D051379:Mice; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D017924:Nucleopolyhedroviruses / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000276:immunology; D020449:Repetitive Sequences, Amino Acid; D012995:Solubility; D018411:Spodoptera / Q000166:cytology; D013329:Structure-Activity Relationship; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D014162:Transfection
chemical_list: D000944:Antigens, Differentiation, B-Lymphocyte; D000949:Histocompatibility Antigens Class II; C474482:I-A(b) antigen, mouse; D007074:Immunoglobulin G; D007518:Isoantibodies; D011993:Recombinant Fusion Proteins; C045084:invariant chain