title: A Comparative Study of the Bone Regenerative Effect of Chemically Modified RNA Encoding BMP-2 or BMP-9.
abstract: Employing cost-effective biomaterials to deliver chemically modified ribonucleic acid (cmRNA) in a controlled manner addresses the high cost, safety concerns, and lower transfection efficiency that exist with protein and gene therapeutic approaches. By eliminating the need for nuclear entry, cmRNA therapeutics can potentially overcome the lower transfection efficiencies associated with non-viral gene delivery systems. Here, we investigated the osteogenic potential of cmRNA-encoding BMP-9, in comparison to cmRNA-encoding BMP-2. Polyethylenimine (PEI) was used as a vector to increase in vitro transfection efficacy. Complexes of PEI-cmRNA (encoding BMP-2 or BMP-9) were fabricated at an amine (N) to phosphate (P) ratio of 10 and characterized for transfection efficacy in vitro using human bone marrow stromal cells (BMSCs). The osteogenic potential of BMSCs treated with these complexes was determined by evaluating the expression of bone-specific genes as well as through the detection of bone matrix deposition. It was found that alkaline phosphatase (ALP) expression 3 days post transfection in the group treated with BMP-9-cmRNA was significantly higher than that in the group that received BMP-2-cmRNA treatment. Alizarin red staining and atomic absorption spectroscopy demonstrated enhanced osteogenic differentiation as evidenced by increased bone matrix production by the BMSCs treated with BMP-9-cmRNA when compared to cells treated with BMP-2-cmRNA. In vivo studies showed increased bone formation in calvarial defects treated with the BMP-9-cmRNA and BMP-2-cmRNA collagen scaffolds when compared to empty defects. The connectivity density of the regenerated bone was higher (2-fold-higher) in the group that received BMP-9-cmRNA compared to BMP-2-cmRNA. Together, these findings suggest that cmRNA-activated matrix encoding osteogenic molecules can provide a powerful strategy for bone regeneration with significant clinical translational potential.
authors.affiliation: Division of Pharmaceutics and Translational Therapeutics, University of Iowa College of Pharmacy, Iowa City, Iowa, USA.
authors.forename: Behnoush
authors.initials: B
authors.lastname: Khorsand
authors.affiliation: Department of Periodontics, University of Iowa College of Dentistry, Iowa City, Iowa, USA. satheeshelangovan@uiowa.edu.
authors.forename: Satheesh
authors.initials: S
authors.lastname: Elangovan
authors.affiliation: Department of Prosthodontics, University of Iowa College of Dentistry, Iowa City, Iowa, USA.
authors.forename: Liu
authors.initials: L
authors.lastname: Hong
authors.affiliation: Department of Pediatrics (Section I), Translational Genomics and Gene Therapy, University of Tübingen, Wilhelmstr. 27, 72074, Tübingen, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Dewerth
authors.affiliation: Department of Pediatrics (Section I), Translational Genomics and Gene Therapy, University of Tübingen, Wilhelmstr. 27, 72074, Tübingen, Germany.
authors.forename: Michael S D
authors.initials: MS
authors.lastname: Kormann
authors.affiliation: Division of Pharmaceutics and Translational Therapeutics, University of Iowa College of Pharmacy, Iowa City, Iowa, USA. aliasger-salem@uiowa.edu.|Department of Periodontics, University of Iowa College of Dentistry, Iowa City, Iowa, USA. aliasger-salem@uiowa.edu.
authors.forename: Aliasger K
authors.initials: AK
authors.lastname: Salem
mesh_terms: D000469:Alkaline Phosphatase / Q000235:genetics; D000818:Animals; D055396:Bone Morphogenetic Protein 2 / Q000235:genetics*; D001861:Bone Regeneration / Q000235:genetics*; D055427:Growth Differentiation Factor 2 / Q000235:genetics*; D006801:Humans; D008297:Male; D059630:Mesenchymal Stem Cells / Q000166:cytology*; D010012:Osteogenesis / Q000235:genetics; D011094:Polyethyleneimine / Q000737:chemistry; D012313:RNA / Q000008:administration & dosage; D011916:Rats, Inbred F344; D014162:Transfection
chemical_list: D055396:Bone Morphogenetic Protein 2; D055427:Growth Differentiation Factor 2; D012313:RNA; D011094:Polyethyleneimine; D000469:Alkaline Phosphatase
keywords: bone morphogenetic protein-2; bone regeneration; chemically modified RNA; gene delivery; signaling pathways