title: Silencing of Antichondrogenic MicroRNA-221 in Human Mesenchymal Stem Cells Promotes Cartilage Repair In Vivo.
abstract: There is a growing demand for the development of experimental strategies for efficient articular cartilage repair. Current tissue engineering-based regenerative strategies make use of human mesenchymal stromal cells (hMSCs). However, when implanted in a cartilage defect, control of hMSCs differentiation toward the chondrogenic lineage remains a significant challenge. We have recently demonstrated that silencing the antichondrogenic regulator microRNA-221 (miR-221) was highly effective in promoting in vitro chondrogenesis of monolayered hMSCs in the absence of the chondrogenic induction factor TGF-β. Here we investigated the feasibility of this approach first in conventional 3D pellet culture and then in an in vivo model. In pellet cultures, we observed that miR-221 silencing was sufficient to drive hMSCs toward chondrogenic differentiation in the absence of TGF-β. In vivo, the potential of miR-221 silenced hMSCs was investigated by first encapsulating the cells in alginate and then by filling a cartilage defect in an osteochondral biopsy. After implanting the biopsy subcutaneously in nude mice, we found that silencing of miR-221 strongly enhanced in vivo cartilage repair compared to the control conditions (untreated hMSCs or alginate-only). Notably, miR-221 silenced hMSCs generated in vivo a cartilaginous tissue with no sign of collagen type X deposition, a marker of undesired hypertrophic maturation. Altogether our data indicate that silencing miR-221 has a prochondrogenic role in vivo, opening new possibilities for the use of hMSCs in cartilage tissue engineering. Stem Cells 2016;34:1801-1811.
authors.affiliation: Department of Biomedical and Specialty Surgical Sciences, University of Ferrara, Ferrara, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Lolli
authors.affiliation: Department of Orthopaedics, Erasmus MC, University Medical Center, CN Rotterdam, The Netherlands.
authors.forename: Roberto
authors.initials: R
authors.lastname: Narcisi
authors.affiliation: Department of Biomedical and Specialty Surgical Sciences, University of Ferrara, Ferrara, Italy.
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Lambertini
authors.affiliation: Department of Biomedical and Specialty Surgical Sciences, University of Ferrara, Ferrara, Italy.
authors.forename: Letizia
authors.initials: L
authors.lastname: Penolazzi
authors.affiliation: Department of Biomedical and Specialty Surgical Sciences, University of Ferrara, Ferrara, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Angelozzi
authors.affiliation: Department of Orthopaedics, Erasmus MC, University Medical Center, CN Rotterdam, The Netherlands.
authors.forename: Nicole
authors.initials: N
authors.lastname: Kops
authors.affiliation: Department of Orthopaedics, Erasmus MC, University Medical Center, CN Rotterdam, The Netherlands.
authors.forename: Simona
authors.initials: S
authors.lastname: Gasparini
authors.affiliation: Department of Orthopaedics, Erasmus MC, University Medical Center, CN Rotterdam, The Netherlands.|Department of Otorhinolaryngology, Erasmus MC, University Medical Center, CN Rotterdam, The Netherlands.
authors.forename: Gerjo J V M
authors.initials: GJ
authors.lastname: van Osch
authors.affiliation: Department of Biomedical and Specialty Surgical Sciences, University of Ferrara, Ferrara, Italy.
authors.forename: Roberta
authors.initials: R
authors.lastname: Piva
mesh_terms: D000818:Animals; D002356:Cartilage / Q000473:pathology*; D002454:Cell Differentiation; D002478:Cells, Cultured; D020219:Chondrogenesis; D004195:Disease Models, Animal; D020868:Gene Silencing; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000378:metabolism*; D008819:Mice, Nude; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D008954:Models, Biological; D012038:Regeneration; D014945:Wound Healing
chemical_list: D035683:MicroRNAs; C525709:MIR221, human
keywords: Chondrogenesis; Gene silencing; In vivo cartilage repair; Mesenchymal stem cells; microRNA-221