title: Immobilization of human mesenchymal stem cells within RGD-grafted alginate microspheres and assessment of their angiogenic potential.
abstract: In this work, human mesenchymal stem cells (hMSC) immobilized in RGD-coupled alginate microspheres, with a binary composition of high and low molecular weight alginate, were investigated. Cells immobilized within RGD-alginate microspheres (during 21 days) showed metabolic activity, with an overall viability higher than 90%, short cell extensions, and, when induced, they were able to differentiate into the osteogenic lineage. In osteogenic conditions (comparing to basal conditions), immobilized cells presented alkaline phosphatase (ALP) activity and an upregulation of ALP, collagen type I, and Runx 2 expression. Moreover, mineralization was also detected in immobilized cells under osteogenic stimulus. In addition, it was demonstrated for the first time that MSCs immobilized in this 3D matrix were able to enhance the ability of neighboring endothelial cells to form tubelike structures. Overall, these findings represent a step forward in the development of injectable stem cell carriers for bone tissue engineering.
authors.affiliation: INEB-Instituto de Engenharia Biomedica, Rua do Campo Alegre No. 823, 4150-180 Porto, Portugal.
authors.forename: Sílvia J
authors.initials: SJ
authors.lastname: Bidarra
authors.forename: Cristina C
authors.initials: CC
authors.lastname: Barrias
authors.forename: Mário A
authors.initials: MA
authors.lastname: Barbosa
authors.forename: Raquel
authors.initials: R
authors.lastname: Soares
authors.forename: Pedro L
authors.initials: PL
authors.lastname: Granja
mesh_terms: D000464:Alginates; D000469:Alkaline Phosphatase / Q000378:metabolism; D001483:Base Sequence; D002454:Cell Differentiation; D024042:Collagen Type I / Q000378:metabolism; D017931:DNA Primers; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000166:cytology* / Q000201:enzymology / Q000378:metabolism; D008855:Microscopy, Electron, Scanning; D008863:Microspheres; D018919:Neovascularization, Physiologic; D009842:Oligopeptides; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D000464:Alginates; D024042:Collagen Type I; D017931:DNA Primers; D009842:Oligopeptides; C047981:arginyl-glycyl-aspartic acid; D000469:Alkaline Phosphatase