title: Secretion of a homodimeric V alpha C kappa T-cell receptor-immunoglobulin chimeric protein.
abstract: Transfection into lymphoid cells of a chimeric T-cell receptor-immunoglobulin gene has been used to generate a secreted water-soluble form of the variable (V) domain of a human T-cell receptor alpha chain for use in structural (i.e. x-ray crystallographic) studies. The chimeric protein consists of the V alpha region of the T-cell receptor of a diphtheria toxoid-specific human T-cell clone fused to a human immunoglobulin kappa light chain constant (C) region. It is efficiently secreted by myeloma cells as a noncovalent homodimer of 65-kDa molecular mass in the absence of either immunoglobulin heavy or light chain. The V alpha C kappa protein is extensively glycosylated, and its secretion is glycosylation-dependent. Chimeric genes containing the V beta region of this particular T-cell receptor linked to immunoglobulin C kappa or C gamma 2 regions are expressed intracellularly, but the products, although glycosylated, are not secreted, nor do they assemble with the V alpha C kappa protein. This suggests that the chimeric beta chain-immunoglobulin proteins are incorrectly folded and/or processed due either to the design of the gene fusions themselves or to the absence of vital T-cell-specific accessory molecules in the myeloma host.
authors.affiliation: Medical Research Council Laboratory of Molecular Biology, Cambridge, United Kingdom.
authors.forename: R A
authors.initials: RA
authors.lastname: Mariuzza
authors.forename: G
authors.initials: G
authors.lastname: Winter
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D004247:DNA / Q000235:genetics; D005803:Genes, Immunoglobulin; D006031:Glycosylation; D007145:Immunoglobulin kappa-Chains / Q000235:genetics / Q000378:metabolism; D066298:In Vitro Techniques; D051379:Mice; D009194:Myeloma Proteins / Q000378:metabolism; D010957:Plasmids; D011499:Protein Processing, Post-Translational; D011948:Receptors, Antigen, T-Cell / Q000235:genetics / Q000378:metabolism*; D016693:Receptors, Antigen, T-Cell, alpha-beta; D011994:Recombinant Proteins / Q000378:metabolism*; D014162:Transfection; D014407:Tumor Cells, Cultured
chemical_list: D007145:Immunoglobulin kappa-Chains; D009194:Myeloma Proteins; D011948:Receptors, Antigen, T-Cell; D016693:Receptors, Antigen, T-Cell, alpha-beta; D011994:Recombinant Proteins; D004247:DNA