title: Screening of synthetic phage display scFv libraries yields competitive ligands of human leptin receptor.
abstract: Initially considered the main endogenous anorexigenic factor, fat-derived leptin turned out to be a markedly pleiotropic hormone, influencing diverse physiological processes. Moreover, hyperleptinemia in obese individuals has been linked to the onset or progression of serious disorders, such as cancer, autoimmune diseases, and atherosclerosis, and antagonizing peripheral leptin's signalization has been shown to improve these conditions. To develop an antibody-based leptin antagonist we have devised a tailored panning procedure and screened two phage display libraries of single chain variable antibody fragments (scFvs) against recombinant leptin receptor. One of the scFvs was expressed in Escherichia coli and its interaction with leptin receptor was characterized in more detail. It was found to recognize a discontinuous epitope and to compete with leptin for receptor binding with IC50 and Kd values in the nanomolar range. The reported scFv represents a lead for development of leptin antagonists that may ultimately find use in therapy of various hyperleptinemia-related disorders.
authors.affiliation: University of Ljubljana, Faculty of Pharmacy, Department of Pharmaceutical Biology, Aškerčeva 7, SI-1000 Ljubljana, Slovenia. Electronic address: peter.molek@ffa.uni-lj.si.
authors.forename: Peter
authors.initials: P
authors.lastname: Molek
authors.affiliation: University of Ljubljana, Faculty of Pharmacy, Department of Pharmaceutical Biology, Aškerčeva 7, SI-1000 Ljubljana, Slovenia. Electronic address: miha.vodnik@ffa.uni-lj.si.
authors.forename: Miha
authors.initials: M
authors.lastname: Vodnik
authors.affiliation: University of Ljubljana, Faculty of Pharmacy, Department of Pharmaceutical Biology, Aškerčeva 7, SI-1000 Ljubljana, Slovenia; Jožef Stefan Institute, Department of Biotechnology, Jamova 39, SI-1000 Ljubljana, Slovenia. Electronic address: borut.strukelj@ffa.uni-lj.si.
authors.forename: Borut
authors.initials: B
authors.lastname: Strukelj
authors.affiliation: University of Ljubljana, Faculty of Pharmacy, Department of Pharmaceutical Biology, Aškerčeva 7, SI-1000 Ljubljana, Slovenia. Electronic address: tomaz.bratkovic@ffa.uni-lj.si.
authors.forename: Tomaž
authors.initials: T
authors.lastname: Bratkovič
mesh_terms: D000918:Antibody Specificity; D001667:Binding, Competitive; D002999:Clone Cells; D000939:Epitopes / Q000737:chemistry / Q000276:immunology; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D057166:High-Throughput Screening Assays; D006801:Humans; D007700:Kinetics; D008024:Ligands; D019151:Peptide Library; D011485:Protein Binding; D054411:Receptors, Leptin / Q000037:antagonists & inhibitors* / Q000276:immunology / Q000378:metabolism; D057127:Single-Chain Antibodies / Q000096:biosynthesis / Q000276:immunology / Q000494:pharmacology*
chemical_list: D000939:Epitopes; C515448:LEPR protein, human; D008024:Ligands; D019151:Peptide Library; D054411:Receptors, Leptin; D057127:Single-Chain Antibodies
keywords: Antagonist; Antibody; Leptin; Phage display; Receptor; scFv