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: Rui Zhang, Jiyuan Yang, Te-Wei Chu, Jonathan M Hartley, Jindřich Kopeček
• Journal: Advanced healthcare materials (Adv Healthc Mater) Vol. 4 Issue 7 Pg. 1054-65 (May 2015) ISSN: 2192-2659 [Electronic] Germany
• PMID: 25612325 (Publication Type: Journal Article, Research Support, N.I.H., Extramural)
• Copyright: © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Chemical References

• Acrylamides
• Antigens, CD20
• Immunoglobulin Fab Fragments
• Lipids
• Membrane Lipids
• Peptides
• N-(2-hydroxypropyl)methacrylamide

Topics

• Acrylamides (immunology)
• Animals
• Antigens, CD20 (immunology)
• Apoptosis (drug effects, immunology)
• Cell Line, Tumor
• Female
• Fluorescence
• Humans
• Immunoglobulin Fab Fragments (immunology)
• Lipids (immunology)
• Lymphoma (drug therapy, immunology)
• Membrane Lipids (immunology)
• Mice, Nude
• Mice, SCID
• Multimodal Imaging (methods)
• Peptides (immunology, therapeutic use)