title: Liposomal modular complexes for simultaneous targeted delivery of bioactive gases and therapeutics.
abstract: Intrinsically echogenic liposomes (ELIP) can be adapted to encapsulate nitric oxide to facilitate ultrasound-enhanced delivery of therapeutic agents to atherosclerotic plaques. However, the NO loading of targeted ELIP caused a 93% decrease of antibody (Ab) immunoreactivity. The following hypothesis was tested: biotin/avidin-mediated coupling of NO-ELIP and Ab-conjugated ELIP will enable co-delivery of bioactive gases and ELIP that can encapsulate other agents without loss of targeting efficiency. Complex formation was initiated by addition of excess streptavidin to equal proportions of biotinylated Ab-ELIP and NO-ELIP. Fluorescence deconvolution microscopy, Coulter Multisizer 3 analysis and flow cytometry demonstrated that the ELIP coupling procedure formed mixed aggregates of >or=10 liposomes within 1 min. Intravascular ultrasound imaging and ELISA showed that echogenicity and targeting efficiency were completely and 69-99% retained, respectively. When complexed to NO-ELIP, ELIP bifunctionally targeted to both CD34 and ICAM-1 (BF-ELIP) increased human mononuclear cell migration through human coronary artery endothelial cell monolayers in transwell plates 4-fold relative to a nonspecific IgG-ELIP control and 2-fold relative to BF-ELIP alone. It was concluded that this novel multi-functional conjugation methodology provides a platform technology for site-specific co-delivery of bioactive gases and other agents.
authors.affiliation: Division of Cardiology, Department of Internal Medicine, University of Texas Health Science Center, 6431 Fannin Street, MSB 1.246, Houston, Texas 77030, USA. Melvin.E.Klegerman@uth.tmc.edu
authors.forename: Melvin E
authors.initials: ME
authors.lastname: Klegerman
authors.forename: Michael
authors.initials: M
authors.lastname: Wassler
authors.forename: Shao-Ling
authors.initials: SL
authors.lastname: Huang
authors.forename: Yuejiao
authors.initials: Y
authors.lastname: Zou
authors.forename: Hyunggun
authors.initials: H
authors.lastname: Kim
authors.forename: Harnath S
authors.initials: HS
authors.lastname: Shelat
authors.forename: Christy K
authors.initials: CK
authors.lastname: Holland
authors.forename: Yong-Jian
authors.initials: YJ
authors.lastname: Geng
authors.forename: David D
authors.initials: DD
authors.lastname: McPherson
mesh_terms: D000911:Antibodies, Monoclonal / Q000008:administration & dosage* / Q000627:therapeutic use; D018952:Antigens, CD34 / Q000276:immunology / Q000378:metabolism; D019921:Biotinylation; D002448:Cell Adhesion; D002465:Cell Movement; D002478:Cells, Cultured; D018920:Coculture Techniques; D003331:Coronary Vessels / Q000166:cytology / Q000000981:diagnostic imaging; D004339:Drug Compounding / Q000379:methods*; D016503:Drug Delivery Systems / Q000379:methods*; D004359:Drug Therapy, Combination; D042783:Endothelial Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D005434:Flow Cytometry; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000276:immunology / Q000378:metabolism; D008081:Liposomes; D008856:Microscopy, Fluorescence; D009569:Nitric Oxide / Q000008:administration & dosage* / Q000627:therapeutic use; D013234:Stem Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D018084:Ultrasonography, Interventional
chemical_list: D000911:Antibodies, Monoclonal; D018952:Antigens, CD34; D008081:Liposomes; D018799:Intercellular Adhesion Molecule-1; D009569:Nitric Oxide