title: Targeting of adenovirus to endothelial cells by a bispecific single-chain diabody directed against the adenovirus fiber knob domain and human endoglin (CD105).
abstract: The use of adenoviruses for antivascular cancer gene therapy is limited by their low transduction efficiency for endothelial cells. We have developed a recombinant bispecific antibody as a molecular bridge, linking the adenovirus capsid to the endothelial cell surface protein endoglin, for vascular targeting of adenoviruses. Endoglin (CD105), a component of the transforming growth factor beta receptor complex, represents a promising target for antivascular cancer therapy. Endoglin is expressed predominantly on endothelial cells and is upregulated in angiogenic areas of tumors. We isolated single-chain Fv fragments directed against human endoglin from a human semisynthetic antibody library. One of the isolated scFv fragments (scFv C4) bound specifically to various proliferating primary endothelial cells or cell lines including HUVEC, HDMEC, HMVEC, and HMEC. ScFv C4 was therefore used to construct a bispecific single-chain diabody directed against endoglin and the adenovirus fiber knob domain (scDb EDG-Ad). This bispecific molecule mediated enhanced and selective adenovirus transduction of HUVECs, which was independent from binding to the coxsackievirus and adenovirus receptor (CAR) and alpha(v)-integrins. Thus, adenovirus infection was redirected to a new cellular receptor (CD105) and cell entry pathway. These results demonstrate the utility of bispecific single-chain diabodies, which can be produced in large quantities in bacteria, for the retargeting of adenoviruses in cancer gene therapy.
authors.affiliation: Institut für Molekularbiologie und Tumorforschung, Philipps-Universität Marburg, Emil-Mannkopff-Strabetae 2, Marburg, D-35033, Germany.
authors.forename: D M
authors.initials: DM
authors.lastname: Nettelbeck
authors.forename: D W
authors.initials: DW
authors.lastname: Miller
authors.forename: V
authors.initials: V
authors.lastname: Jérôme
authors.forename: M
authors.initials: M
authors.lastname: Zuzarte
authors.forename: S J
authors.initials: SJ
authors.lastname: Watkins
authors.forename: R E
authors.initials: RE
authors.lastname: Hawkins
authors.forename: R
authors.initials: R
authors.lastname: Müller
authors.forename: R E
authors.initials: RE
authors.lastname: Kontermann
mesh_terms: D000256:Adenoviridae / Q000235:genetics* / Q000276:immunology; D018033:Antibodies, Bispecific / Q000235:genetics*; D000914:Antibodies, Viral / Q000235:genetics; D015703:Antigens, CD; D001483:Base Sequence; D015153:Blotting, Western; D002478:Cells, Cultured / Q000378:metabolism; D003001:Cloning, Molecular; D000071063:Endoglin; D004730:Endothelium, Vascular / Q000276:immunology / Q000502:physiology; D004797:Enzyme-Linked Immunosorbent Assay; D005434:Flow Cytometry; D018390:Gene Targeting / Q000379:methods; D015316:Genetic Therapy / Q000379:methods*; D005822:Genetic Vectors; D006801:Humans; D015151:Immunoblotting; D007128:Immunoglobulin Fragments / Q000276:immunology; D007135:Immunoglobulin Variable Region / Q000276:immunology; D008969:Molecular Sequence Data; D019151:Peptide Library; D010456:Peptides, Cyclic / Q000378:metabolism; D011956:Receptors, Cell Surface; D011994:Recombinant Proteins / Q000378:metabolism; D014471:Umbilical Veins / Q000502:physiology; D019010:Vascular Cell Adhesion Molecule-1 / Q000235:genetics* / Q000276:immunology
chemical_list: D018033:Antibodies, Bispecific; D000914:Antibodies, Viral; D015703:Antigens, CD; C064206:ENG protein, human; D000071063:Endoglin; D007128:Immunoglobulin Fragments; D007135:Immunoglobulin Variable Region; D019151:Peptide Library; D010456:Peptides, Cyclic; D011956:Receptors, Cell Surface; D011994:Recombinant Proteins; D019010:Vascular Cell Adhesion Molecule-1