title: Engineering and characterization of a murine MHC class II-immunoglobulin chimera expressing an immunodominant CD4 T viral epitope.
abstract: T cells recognize peptides derived from the processing of proteins by antigen presenting cells (APCs) in association with the major histocompatibility complex (MHC) molecules. We have engineered a murine MHC class II antigen presenting molecule consisting of the extracellular domains of I-E(d)alpha and I-E(d)beta chains to which the CD4 T cell immunodominant epitope HA110-120 of the hemagglutinin (HA) of the A/PR/8/34 influenza virus was covalently linked at the N-terminus of the I-E(d)beta chain. The HA110-120-I-E(d)alphabeta complex was dimerized by the Fc portion of an IgG2a linked at the C-terminus of the I-E(d)beta chain. SF9 insect cells infected with baculovirus carrying both I-E(d)alpha and HA110-120-I-E(d)beta-Fcgamma2a genes, secreted a disulfide-stabilized dimer of the HA110-120-I-E(d)alphabeta-Fcgamma2a molecule, designated as DEF. The chimeric molecule preserved the structural integrity of both MHC-peptide complex and Fc portion of IgG2a, and was able to: (i) bind specifically to the cognate T cell receptors (TCRs) and to the immunoglobulin FcgammaRII receptor (FcR), (ii) induce complement-mediated cell cytotoxicity, and (iii) trigger early production of IL-2 in cognate T cells. Chimeric antigen presenting molecules with these characteristics may represent a novel platform for the development of immunomodulatory agents of therapeutic use.
authors.affiliation: The Department of Microbiology, Mount Sinai School of Medicine, New York, NY 10029, USA.
authors.forename: S
authors.initials: S
authors.lastname: Casares
authors.forename: C A
authors.initials: CA
authors.lastname: Bona
authors.forename: T D
authors.initials: TD
authors.lastname: Brumeanu
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D016367:Baculoviridae / Q000235:genetics; D001483:Base Sequence; D015704:CD4 Antigens / Q000235:genetics* / Q000276:immunology; D003602:Cytotoxicity, Immunologic; D019281:Dimerization; D000939:Epitopes / Q000235:genetics; D019267:Hemagglutinin Glycoproteins, Influenza Virus / Q000235:genetics / Q000276:immunology; D000949:Histocompatibility Antigens Class II / Q000737:chemistry / Q000235:genetics* / Q000276:immunology; D007141:Immunoglobulin Fc Fragments / Q000235:genetics; D007074:Immunoglobulin G / Q000737:chemistry / Q000235:genetics* / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D008822:Mice, Transgenic; D008969:Molecular Sequence Data; D015202:Protein Engineering; D011961:Receptors, Fc / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics; D018411:Spodoptera
chemical_list: D015704:CD4 Antigens; D000939:Epitopes; D019267:Hemagglutinin Glycoproteins, Influenza Virus; D000949:Histocompatibility Antigens Class II; D007141:Immunoglobulin Fc Fragments; D007074:Immunoglobulin G; D011961:Receptors, Fc; D011993:Recombinant Fusion Proteins