title: Photoactivated miR-148b-nanoparticle conjugates improve closure of critical size mouse calvarial defects.
abstract: Inducible systems providing temporal control of differentiation have the potential to improve outcomes in surgical reconstruction and regenerative medicine by precise modulation of wound healing and tissue repair processes. The aim of this study was to demonstrate that nanoformulated microRNA (miRNA) conjugates activated via photo exposure can lead to the induced osteogenic differentiation of human adipose-derived stromal/stem cells (hASCs) in vivo. The conjugate PC-miR-148b-SNP, a mimic of miRNA-148b tethered to silver nanoparticles (SNPs) via a photolabile linker, was used to modulate gene expression for improved closure of a critical size defect drilled on the right parietal bone of male CD-1 nude homozygous mice. The PC-miR-148b-SNP conjugates added to hASCs and loaded to either Matrigel or polycaprolactone (PCL) scaffolds resulted in different levels of healing of the defect. After 4 and 12weeks, 3-D micro-computed tomography reconstructed images indicate statistically significant defect closure from 3.83±1.19% to 5.46±2.01% and 6.54±4.28% to 32.53±8.3% for non-photoactivated and photoactivated conjugates, respectively, in the PCL scaffolds. The results were confirmed with H&E and Masson's Trichrome stains in the transverse sections of photoactivated conjugates. Collagen fiber staining was greatest at 12weeks when it reached approximately the same density and thickness as the native calvarium. This technology provides a platform that can be used with other miRNAs that actively govern the pathways responsible for regenerative and wound healing processes.
authors.affiliation: Department of Biological and Agricultural Engineering, Louisiana State University and LSU AgCenter, Baton Rouge, LA 70803, USA.
authors.forename: Ammar T
authors.initials: AT
authors.lastname: Qureshi
authors.affiliation: Department of Biological and Agricultural Engineering, Louisiana State University and LSU AgCenter, Baton Rouge, LA 70803, USA.
authors.forename: Andrew
authors.initials: A
authors.lastname: Doyle
authors.affiliation: Department of Biological and Agricultural Engineering, Louisiana State University and LSU AgCenter, Baton Rouge, LA 70803, USA.
authors.forename: Cong
authors.initials: C
authors.lastname: Chen
authors.affiliation: School of Animal Sciences, Louisiana State University AgCenter, Baton Rouge, LA 70803, USA.
authors.forename: Diana
authors.initials: D
authors.lastname: Coulon
authors.affiliation: Department of Orthopedics, Louisiana State University Health Science Center, New Orleans, LA 70115, USA.
authors.forename: Vinod
authors.initials: V
authors.lastname: Dasa
authors.affiliation: Department of PathoBiological Sciences, School of Veterinary Medicine, Louisiana State University System, Baton Rouge, LA 70803, USA.
authors.forename: Fabio
authors.initials: F
authors.lastname: Del Piero
authors.affiliation: Section of Plastic Surgery, Division of Burn Surgery, University of Michigan, Ann Arbor, MI 48109, USA.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Levi
authors.affiliation: Department of Biological and Agricultural Engineering, Louisiana State University and LSU AgCenter, Baton Rouge, LA 70803, USA.
authors.forename: W Todd
authors.initials: WT
authors.lastname: Monroe
authors.affiliation: Center for Stem Cell Research and Regenerative Medicine, Tulane University School of Medicine, New Orleans, LA 70112, USA.
authors.forename: Jeffrey M
authors.initials: JM
authors.lastname: Gimble
authors.affiliation: Department of Biological and Agricultural Engineering, Louisiana State University and LSU AgCenter, Baton Rouge, LA 70803, USA. Electronic address: danielhayes@lsu.edu.
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Hayes
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D051379:Mice; D035683:MicroRNAs / Q000502:physiology*; D053758:Nanoparticles; D010777:Photochemistry; D012886:Skull / Q000473:pathology*; D055114:X-Ray Microtomography
chemical_list: D035683:MicroRNAs; C554644:Mirn148 microRNA, mouse
keywords: Calvarial size defect (CSD); Osteogenic differentiation; Photoactivated delivery system; miR-148b