title: Differential activation of TRAIL-R1 and -2 by soluble and membrane TRAIL allows selective surface antigen-directed activation of TRAIL-R2 by a soluble TRAIL derivative.
abstract: TNF-related apoptosis-inducing ligand (TRAIL) is a typical member of the tumor necrosis factor (TNF) ligand family that is expressed as a type II membrane protein (memTRAIL) and signals apoptosis via the death domain-containing receptors TRAIL-R1 and -2. Soluble recombinant derivatives of TRAIL (sTRAIL) are considered as novel tumors therapeutics because of their selective apoptosis inducing activity in a variety of human tumors but not in normal cells. Using antagonistic antigen-binding fragment (Fab) preparations of TRAIL-R1- and TRAIL-R2-specific antibodies, we demonstrate in this study that TRAIL-R1 becomes activated by both the soluble and the membrane-bound form of the ligand, whereas TRAIL-R2 becomes only activated by memTRAIL or soluble TRAIL secondarily cross-linked by antibodies. Furthermore, we show that the restricted signal capacity of sTRAIL can be readily converted into a fully signal competent memTRAIL-like molecule, i.e. a TRAIL-R2 stimulating ligand, by genetic fusion to an antibody derivative that allows antigen-dependent 'immobilization' of the fusion protein to cell surfaces. We conclude that antibody targeting-dependent activation can be used to design selective therapeutics derived of those ligands of the TNF family that are biologically inactive in their soluble form.
authors.affiliation: Institute of Cell Biology and Immunology, University of Stuttgart, Allmandring 31, 70569 Stuttgart, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Wajant
authors.forename: D
authors.initials: D
authors.lastname: Moosmayer
authors.forename: T
authors.initials: T
authors.lastname: Wüest
authors.forename: T
authors.initials: T
authors.lastname: Bartke
authors.forename: E
authors.initials: E
authors.lastname: Gerlach
authors.forename: U
authors.initials: U
authors.lastname: Schönherr
authors.forename: N
authors.initials: N
authors.lastname: Peters
authors.forename: P
authors.initials: P
authors.lastname: Scheurich
authors.forename: K
authors.initials: K
authors.lastname: Pfizenmaier
mesh_terms: D000818:Animals; D000918:Antibody Specificity; D000954:Antigens, Surface / Q000276:immunology*; D000970:Antineoplastic Agents / Q000737:chemistry; D017209:Apoptosis / Q000187:drug effects; D051017:Apoptosis Regulatory Proteins; D019556:COS Cells; D002522:Chlorocebus aethiops; D015195:Drug Design; D006367:HeLa Cells / Q000187:drug effects; D006801:Humans; D007140:Immunoglobulin Fab Fragments; D019169:Jurkat Cells / Q000187:drug effects; D007624:KB Cells / Q000187:drug effects; D008024:Ligands; D008562:Membrane Glycoproteins / Q000737:chemistry / Q000494:pharmacology*; D008565:Membrane Proteins / Q000737:chemistry / Q000494:pharmacology; D009363:Neoplasm Proteins / Q000187:drug effects / Q000276:immunology / Q000502:physiology; D017434:Protein Structure, Tertiary; D053220:Receptors, TNF-Related Apoptosis-Inducing Ligand; D018124:Receptors, Tumor Necrosis Factor / Q000187:drug effects / Q000276:immunology / Q000502:physiology*; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000494:pharmacology; D015398:Signal Transduction / Q000187:drug effects* / Q000502:physiology; D012995:Solubility; D053221:TNF-Related Apoptosis-Inducing Ligand; D014409:Tumor Necrosis Factor-alpha / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D000954:Antigens, Surface; D000970:Antineoplastic Agents; D051017:Apoptosis Regulatory Proteins; D007140:Immunoglobulin Fab Fragments; D008024:Ligands; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D009363:Neoplasm Proteins; D053220:Receptors, TNF-Related Apoptosis-Inducing Ligand; D018124:Receptors, Tumor Necrosis Factor; D011993:Recombinant Fusion Proteins; D053221:TNF-Related Apoptosis-Inducing Ligand; C105190:TNFRSF10A protein, human; C505639:TNFRSF10B protein, human; C505653:TNFSF10 protein, human; D014409:Tumor Necrosis Factor-alpha