title: Comparison of three different forms of HLA-DR4Dw4 proteins.
abstract: The biochemical behavior and peptide binding properties of a soluble form of the human class II DR4Dw4 molecule (PI-DR4Dw4) were compared to DR4Dw4 molecules containing the transmembrane and cytoplasmic domains that were purified both from B and transfected chinese hamster ovary cells. Recombinant and B cell-derived DR4Dw4 molecules bound monoclonal anti-DR4Dw4 antibodies with different affinities and varied in their stability in the presence of sodium dodecyl sulfate. The three forms of DR4Dw4 bound peptides with a similar apparent affinity constant, but soluble class II molecules bound up to ten times more peptide than DR4Dw4 containing a transmembrane region. Peptide binding kinetics for soluble DR4Dw4 molecules were 10-20 times faster than for the other two forms of DR4Dw4 molecules. Finally, soluble PI-DR4Dw4/peptide complexes were shown to stimulate T cell proliferation.
authors.affiliation: Immunologic Pharmaceutical Corporation, Palo Alto, CA 94304.
authors.forename: R
authors.initials: R
authors.lastname: Buelow
authors.forename: L R
authors.initials: LR
authors.lastname: Paborsky
authors.forename: W C
authors.initials: WC
authors.lastname: van Schooten
authors.forename: T J
authors.initials: TJ
authors.lastname: Kummerehl
authors.forename: R
authors.initials: R
authors.lastname: Schreifels
authors.forename: K
authors.initials: K
authors.lastname: Marshall
authors.forename: J
authors.initials: J
authors.lastname: Mayer
authors.forename: J B
authors.initials: JB
authors.lastname: Rothbard
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D001483:Base Sequence; D016466:CHO Cells; D002241:Carbohydrates / Q000032:analysis; D006224:Cricetinae; D004797:Enzyme-Linked Immunosorbent Assay; D006684:HLA-DR Antigens / Q000032:analysis* / Q000276:immunology / Q000378:metabolism; D008213:Lymphocyte Activation; D008969:Molecular Sequence Data; D010455:Peptides / Q000378:metabolism; D011487:Protein Conformation; D013601:T-Lymphocytes / Q000276:immunology; D014162:Transfection
chemical_list: D000911:Antibodies, Monoclonal; D002241:Carbohydrates; D006684:HLA-DR Antigens; D010455:Peptides