title: Use of a solid-phase random peptide library to identify inhibitors of TNF-alpha mediated cytotoxicity in vitro.
abstract: Tumour necrosis factor (TNF) is a pleiotropic cytokine which plays a central role in infection, inflammation and autoimmune diseases. Its functions are mediated through binding to high affinity cell surface receptors. An approach to modulate excessive levels of TNF-alpha in the serum is the use of soluble receptors. In this study the potential of a solid-phase combinatorial peptide library was investigated to identify peptide mimics of the binding site of the TNF-alpha receptor. One of the identified mimotopes was shown to inhibit TNF-alpha-mediated cytotoxicity in mouse L929 and in a human KYM-1D4 cell lines in a dose-dependent fashion. Characterization of the mimotope sequence by high-performance liquid chromatography and mass spectroscopy has shown that the inhibitory effect of the mimotope was dependent upon the presence of a protective MTR group on the side chains of the arginine residues in the mimotope sequence. Furthermore, antibodies to the mimotope were shown to recognize the recombinant human TNF 55-kDa receptor in an ELISA assay. These findings highlight the potential of combinatorial peptide libraries in identifying peptide mimics of the binding site of TNF-alpha receptor, which can be used as competitive inhibitors of ligand-receptor interactions.
authors.affiliation: Department of Clinical Sciences, London School of Hygiene and Tropical Medicine.
authors.forename: C L
authors.initials: CL
authors.lastname: Chirinos-Rojas
authors.forename: M W
authors.initials: MW
authors.lastname: Steward
authors.forename: C D
authors.initials: CD
authors.lastname: Partidos
mesh_terms: D000818:Animals; D000918:Antibody Specificity; D000941:Antigens / Q000276:immunology; D002460:Cell Line; D003602:Cytotoxicity, Immunologic / Q000187:drug effects*; D004797:Enzyme-Linked Immunosorbent Assay; D000939:Epitopes / Q000276:immunology / Q000378:metabolism / Q000494:pharmacology; D005260:Female; D051379:Mice; D008807:Mice, Inbred BALB C; D019151:Peptide Library; D010455:Peptides / Q000138:chemical synthesis / Q000737:chemistry / Q000276:immunology / Q000494:pharmacology; D012208:Rhabdomyosarcoma / Q000276:immunology; D014407:Tumor Cells, Cultured; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors* / Q000276:immunology / Q000378:metabolism / Q000633:toxicity*
chemical_list: D000941:Antigens; D000939:Epitopes; D019151:Peptide Library; D010455:Peptides; D014409:Tumor Necrosis Factor-alpha