title: Blockade of interleukin-13-mediated cell activation by a novel inhibitory antibody to human IL-13 receptor alpha1.
abstract: Interleukin-13 (IL-13) is a cytokine with a crucial role in the development of allergic asthma. The IL-13 receptor shares the IL-4Ralpha subunit with the IL-4R system, but contains as a specific component the IL-13Ralpha1 chain. Blocking signal release by IL-13 without affecting IL-4 function is a potentially interesting therapeutical option for the treatment of asthma. Employing genetic immunization, we generated a set of novel monoclonal antibodies to the IL-13Ralpha1 receptor that proved very specific and efficient inhibitors of human IL-13 activity. Receptor binding antibodies were identified by their specific reactivity with both human monocytes and a murine pro-B cell line overexpressing human IL-13Ralpha1 by flow cytometry and cell ELISA. A luciferase reporter cell system based on STAT6-mediated promoter activation in murine Ba/F3 cells was employed to screen the antibodies for IL-13 antagonistic properties. Inhibitory antibody effects were quantified by interference with IL-13-dependent proliferation of TF-1 cells. The capability of blocking IL-13-driven responses of primary, inflammation-relevant cells was tested by Western blot analysis of STAT6 tyrosine phosphorylation and expression of 15-lipoxygenase in monocytes from fresh blood. The most potent inhibitory antibody identified, GM1E7, inhibited IL-13-driven gene activation and cell proliferation in immune cell lines with IC(50) values in the low nanomolar range. Both short-term (STAT6 activation) and long-term (15-LO induction) responses of primary human blood cells to IL-13 were almost entirely blocked, whereas IL-4 effects remained virtually unaffected. GM1E7 is superior to available agents interfering with IL-13 activity in terms of specificity and efficiency and offers potential novel therapeutic perspectives for the treatment of allergic asthma.
authors.affiliation: Institute of Biochemistry I, Friedrich Schiller University of Jena Medical School, Nonnenplan 2, D-07743 Jena, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Krause
authors.forename: Jochen
authors.initials: J
authors.lastname: Behrends
authors.forename: Andreas
authors.initials: A
authors.lastname: Borowski
authors.forename: Jens
authors.initials: J
authors.lastname: Lohrmann
authors.forename: Stefan
authors.initials: S
authors.lastname: Lang
authors.forename: Daniel
authors.initials: D
authors.lastname: Myrtek
authors.forename: Thomas
authors.initials: T
authors.lastname: Lorenzen
authors.forename: J Christian
authors.initials: JC
authors.lastname: Virchow
authors.forename: Werner
authors.initials: W
authors.lastname: Luttmann
authors.forename: Karlheinz
authors.initials: K
authors.lastname: Friedrich
mesh_terms: D000911:Antibodies, Monoclonal / Q000276:immunology*; D000918:Antibody Specificity / Q000276:immunology; D001093:Arachidonate 15-Lipoxygenase / Q000378:metabolism; D001666:Binding Sites, Antibody / Q000276:immunology; D045744:Cell Line, Tumor; D004305:Dose-Response Relationship, Drug; D006801:Humans; D006825:Hybridomas; D020128:Inhibitory Concentration 50; D018793:Interleukin-13 / Q000037:antagonists & inhibitors* / Q000276:immunology*; D053661:Interleukin-13 Receptor alpha1 Subunit; D009000:Monocytes / Q000166:cytology* / Q000187:drug effects / Q000201:enzymology / Q000276:immunology*; D019000:Phosphotyrosine; D018123:Receptors, Interleukin / Q000037:antagonists & inhibitors* / Q000378:metabolism; D053660:Receptors, Interleukin-13; D050800:STAT6 Transcription Factor / Q000378:metabolism; D013997:Time Factors
chemical_list: D000911:Antibodies, Monoclonal; C508181:IL13RA1 protein, human; D018793:Interleukin-13; D053661:Interleukin-13 Receptor alpha1 Subunit; D018123:Receptors, Interleukin; D053660:Receptors, Interleukin-13; D050800:STAT6 Transcription Factor; D019000:Phosphotyrosine; D001093:Arachidonate 15-Lipoxygenase