title: Discovery and Characterization of a Potent and Specific Peptide Ligand Targeting Endothelial Progenitor Cells and Endothelial Cells for Tissue Regeneration.
abstract: Endothelial progenitor cells (EPCs) and endothelial cells (ECs) play a vital role in endothelialization and vascularization for tissue regeneration. Various EPC/EC targeting biomolecules have been investigated to improve tissue regeneration with limited success often due to their limited functional specificity and structural stability. One-bead one-compound (OBOC) combinatorial technology is an ultrahigh throughput chemical library synthesis and screening method suitable for ligand discovery against a wide range of biological targets, such as integrins. In this study, using primary human EPCs/ECs as living probes, we identified an αvβ3 integrin ligand LXW7 discovered by OBOC combinatorial technology as a potent and specific EPC/EC targeting ligand. LXW7 overcomes the major barriers of other functional biomolecules that have previously been used to improve vascularization for tissue regeneration and possesses optimal stability, EPC/EC specificity, and functionality. LXW7 is a disulfide cyclic octa-peptide (cGRGDdvc) containing unnatural amino acids flanking both sides of the main functional motif; therefore it will be more resistant to proteolysis and more stable in vivo compared to linear peptides and peptides consisting of only natural amino acids. Compared with the conventional αvβ3 integrin ligand GRGD peptide, LXW7 showed stronger binding affinity to primary EPCs/ECs but weaker binding to platelets and no binding to THP-1 monocytes. In addition, ECs bound to the LXW7 treated culture surface exhibited enhanced biological functions such as proliferation, likely due to increased phosphorylation of VEGF receptor 2 (VEGF-R2) and activation of mitogen-activated protein kinase (MAPK) ERK1/2. Surface modification of electrospun microfibrous PLLA/PCL biomaterial scaffolds with LXW7 via Click chemistry resulted in significantly improved endothelial coverage. LXW7 and its derivatives hold great promise for EPC/EC recruitment and delivery and can be widely applied to functionalize various biological and medical materials to improve endothelialization and vascularization for tissue regeneration applications.
authors.affiliation: Institute of Biochemical and Biotechnological Drug, School of Pharmaceutical Science, Shandong University , Jinan, Shandong 250012, China.|Surgical Bioengineering Laboratory, Department of Surgery, School of Medicine, University of California Davis , Sacramento, California 95817, United States.
authors.forename: Dake
authors.initials: D
authors.lastname: Hao
authors.affiliation: Department of Biochemistry and Molecular Medicine, School of Medicine, University of California Davis , Sacramento, California 95817, United States.
authors.forename: Wenwu
authors.initials: W
authors.lastname: Xiao
authors.affiliation: Department of Biochemistry and Molecular Medicine, School of Medicine, University of California Davis , Sacramento, California 95817, United States.
authors.forename: Ruiwu
authors.initials: R
authors.lastname: Liu
authors.affiliation: Surgical Bioengineering Laboratory, Department of Surgery, School of Medicine, University of California Davis , Sacramento, California 95817, United States.
authors.forename: Priyadarsini
authors.initials: P
authors.lastname: Kumar
authors.affiliation: Department of Biochemistry and Molecular Medicine, School of Medicine, University of California Davis , Sacramento, California 95817, United States.
authors.forename: Yuanpei
authors.initials: Y
authors.lastname: Li
authors.affiliation: Institute for Regenerative Cures, University of California Davis Medical Center , Sacramento, California 95817, United States.
authors.forename: Ping
authors.initials: P
authors.lastname: Zhou
authors.affiliation: Institute for Pediatric Regenerative Medicine, Shriners Hospitals for Children , Sacramento, California 95817, United States.
authors.forename: Fuzheng
authors.initials: F
authors.lastname: Guo
authors.affiliation: Surgical Bioengineering Laboratory, Department of Surgery, School of Medicine, University of California Davis , Sacramento, California 95817, United States.
authors.forename: Diana L
authors.initials: DL
authors.lastname: Farmer
authors.affiliation: Department of Biochemistry and Molecular Medicine, School of Medicine, University of California Davis , Sacramento, California 95817, United States.
authors.forename: Kit S
authors.initials: KS
authors.lastname: Lam
authors.affiliation: Institute of Biochemical and Biotechnological Drug, School of Pharmaceutical Science, Shandong University , Jinan, Shandong 250012, China.
authors.forename: Fengshan
authors.initials: F
authors.lastname: Wang
authors.affiliation: Surgical Bioengineering Laboratory, Department of Surgery, School of Medicine, University of California Davis , Sacramento, California 95817, United States.
authors.forename: Aijun
authors.identifier: 0000-0002-2985-3627
authors.initials: A
authors.lastname: Wang
mesh_terms: D001665:Binding Sites; D002448:Cell Adhesion; D002478:Cells, Cultured; D055808:Drug Discovery; D042783:Endothelial Cells / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D066026:Endothelial Progenitor Cells / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D016023:Integrins / Q000378:metabolism; D008024:Ligands; D010455:Peptides / Q000494:pharmacology*; D012038:Regeneration; D054457:Tissue Scaffolds
chemical_list: D016023:Integrins; D008024:Ligands; D010455:Peptides