title: Multimodality imaging of coiled-coil mediated self-assembly in a "drug-free" therapeutic system.
abstract: Two complementary coiled-coil peptides CCE/CCK are used to develop a "drug free" therapeutic system, which can specifically kill cancer cells without a drug. CCE is attached to the Fab' fragment of anti-CD20 1F5 antibody (Fab'-CCE), and CCK is conjugated in multiple grafts to poly[N-(2-hydroxypropyl)methacrylamide] (P-(CCK)x ). Two conjugates are consecutively administered: First, Fab'-CCE coats peptide CCE at CD20 antigen of lymphoma cell surface; second, CCE/CCK biorecognition between Fab'-CCE and P-(CCK)x leads to coiled-coil formation, CD20 crosslinking, membrane reorganization, and ultimately cell apoptosis. To prove that two conjugates can assemble at cell surface, multiple fluorescence imaging studies are performed, including 2-channel FMT, 3D confocal microscopy, and 4-color FACS. Confocal microscopy shows colocalization of two fluorescently labeled conjugates on non-Hodgkin's lymphoma (NHL) Raji cell surface, indicating "two-step" targeting specificity. The fluorescent images also reveal that these two conjugates can disrupt normal membrane lipid distribution and form lipid raft clusters, leading to cancer cell apoptosis. This "two-step" biorecognition capacity is further demonstrated in a NHL xenograft model, using fluorescent images at whole-body, tissue and cell levels. It is also found that delaying injection of P-(CCK)x can significantly enhance targeting efficacy. This high-specificity therapeutics provide a safe option to treat NHL and other B cell malignancies.
authors.affiliation: Department of Pharmaceutics and Pharmaceutical Chemistry/CCCD, University of Utah, Salt Lake City, UT, 84112, USA.
authors.forename: Rui
authors.initials: R
authors.lastname: Zhang
authors.affiliation: Department of Pharmaceutics and Pharmaceutical Chemistry/CCCD, University of Utah, Salt Lake City, UT, 84112, USA.
authors.forename: Jiyuan
authors.initials: J
authors.lastname: Yang
authors.affiliation: Department of Pharmaceutics and Pharmaceutical Chemistry/CCCD, University of Utah, Salt Lake City, UT, 84112, USA.
authors.forename: Te-Wei
authors.initials: TW
authors.lastname: Chu
authors.affiliation: Department of Bioengineering, University of Utah, Salt Lake City, UT, 84112, USA.
authors.forename: Jonathan M
authors.initials: JM
authors.lastname: Hartley
authors.affiliation: Department of Pharmaceutics and Pharmaceutical Chemistry/CCCD, University of Utah, Salt Lake City, UT, 84112, USA.|Department of Bioengineering, University of Utah, Salt Lake City, UT, 84112, USA.
authors.forename: Jindřich
authors.initials: J
authors.lastname: Kopeček
mesh_terms: D000178:Acrylamides / Q000276:immunology; D000818:Animals; D018951:Antigens, CD20 / Q000276:immunology; D017209:Apoptosis / Q000187:drug effects / Q000276:immunology; D045744:Cell Line, Tumor; D005260:Female; D005453:Fluorescence; D006801:Humans; D007140:Immunoglobulin Fab Fragments / Q000276:immunology*; D008055:Lipids / Q000276:immunology; D008223:Lymphoma / Q000188:drug therapy* / Q000276:immunology*; D008563:Membrane Lipids / Q000276:immunology; D008819:Mice, Nude; D016513:Mice, SCID; D064847:Multimodal Imaging / Q000379:methods; D010455:Peptides / Q000276:immunology* / Q000627:therapeutic use*
chemical_list: D000178:Acrylamides; D018951:Antigens, CD20; D007140:Immunoglobulin Fab Fragments; D008055:Lipids; D008563:Membrane Lipids; D010455:Peptides; C032976:N-(2-hydroxypropyl)methacrylamide
keywords: coiled-coils; crosslinking; lipid raft clusters; non-Hodgkin's lymphoma