title: Conditional human VEGF-mediated vascularization in chicken embryos using a novel temperature-inducible gene regulation (TIGR) system.
abstract: Advanced heterologous transcription control systems for adjusting desired transgene expression are essential for gene function assignments, drug discovery, manufacturing of difficult to produce protein pharmaceuticals and precise dosing of gene-based therapeutic interventions. Conversion of the Streptomyces albus heat shock response regulator (RheA) into an artificial eukaryotic transcription factor resulted in a vertebrate thermosensor (CTA; cold-inducible transactivator), which is able to adjust transcription initiation from chimeric target promoters (P(CTA)) in a low-temperature- inducible manner. Evaluation of the temperature-dependent CTA-P(CTA) interaction using a tailored ELISA-like cell-free assay correlated increased affinity of CTA for P(CTA) with temperature downshift. The temperature-inducible gene regulation (TIGR) system enabled tight repression in the chicken bursal B-cell line DT40 at 41 degrees C as well as precise titration of model product proteins up to maximum expression at or below 37 degrees C. Implantation of microencapsulated DT40 cells engineered for TIGR-controlled expression of the human vascular endothelial growth factor A (hVEGF121) provided low-temperature-induced VEGF-mediated vascularization in chicken embryos.
authors.affiliation: Institute of Biotechnology, Swiss Federal Institute of Technology Zurich, ETH Hoenggerberg, CH-8093 Zurich, Switzerland.
authors.forename: Wilfried
authors.initials: W
authors.lastname: Weber
authors.forename: René R
authors.initials: RR
authors.lastname: Marty
authors.forename: Nils
authors.initials: N
authors.lastname: Link
authors.forename: Martin
authors.initials: M
authors.lastname: Ehrbar
authors.forename: Bettina
authors.initials: B
authors.lastname: Keller
authors.forename: Cornelia C
authors.initials: CC
authors.lastname: Weber
authors.forename: Andreas H
authors.initials: AH
authors.lastname: Zisch
authors.forename: Christoph
authors.initials: C
authors.lastname: Heinzen
authors.forename: Valentin
authors.initials: V
authors.lastname: Djonov
authors.forename: Martin
authors.initials: M
authors.lastname: Fussenegger
mesh_terms: D000818:Animals; D001426:Bacterial Proteins; D001808:Blood Vessels / Q000033:anatomy & histology / Q000254:growth & development; D002474:Cell-Free System; D002642:Chick Embryo; D003080:Cold Temperature; D016228:Endothelial Growth Factors / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000235:genetics* / Q000378:metabolism; D008222:Lymphokines / Q000235:genetics* / Q000378:metabolism; D018919:Neovascularization, Physiologic; D011401:Promoter Regions, Genetic; D015202:Protein Engineering; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism; D013696:Temperature; D015534:Trans-Activators / Q000235:genetics / Q000378:metabolism; D015533:Transcriptional Activation; D014162:Transfection; D019076:Transgenes; D014407:Tumor Cells, Cultured; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors
chemical_list: D001426:Bacterial Proteins; D016228:Endothelial Growth Factors; D036341:Intercellular Signaling Peptides and Proteins; D008222:Lymphokines; D012097:Repressor Proteins; C406736:RheA protein, Streptomyces albus; D015534:Trans-Activators; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors