title: Roles of type VI collagen and decorin in human mesenchymal stem cell biophysics during chondrogenic differentiation.
abstract: Human mesenchymal stem cells (hMSCs) induced towards chondrogenesis develop a pericellular matrix (PCM), rich in type VI collagen (ColVI) and proteoglycans such as decorin (DCN). Individual PCM protein functions still need to be elucidated to fully understand the mechanobiological role of this matrix. In this study we identified ColVI and DCN as important contributors in the mechanical function of the PCM and as biochemical modulators during chondrogenesis through targeted knockdown using shRNA lentiviral vectors. Gene expression, western blotting, immunofluorescence and cell deformation analysis were examined at 7, 14 and 28 days post chondrogenic induction. ColVI and DCN knockdown each affected gene expression of acan, bgn, and sox9 during chondrogenesis. ColVI was found to be of central importance in resisting applied strains, while DCN knockdown had strain dependent effects on deformation. We demonstrate that by using genetic engineering to control the biophysical microenvironment created by differentiating cells, it may be possible to guide cellular mechanotransduction.
authors.affiliation: Jeong H. Kim Engineering Building, Room 3242, College Park, MD 20742, USA.hsieh@umd.edu.
authors.forename: J D
authors.initials: JD
authors.lastname: Twomey
authors.forename: P I
authors.initials: PI
authors.lastname: Thakore
authors.forename: D A
authors.initials: DA
authors.lastname: Hartman
authors.forename: E G H
authors.initials: EG
authors.lastname: Myers
authors.forename: A H
authors.initials: AH
authors.lastname: Hsieh
mesh_terms: D053674:Aggrecans / Q000235:genetics / Q000378:metabolism; D058578:Biglycan / Q000235:genetics / Q000378:metabolism; D002460:Cell Line; D020219:Chondrogenesis; D024142:Collagen Type VI / Q000235:genetics / Q000378:metabolism*; D058575:Decorin / Q000235:genetics / Q000378:metabolism*; D005109:Extracellular Matrix / Q000378:metabolism; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000378:metabolism*; D055758:SOX9 Transcription Factor / Q000235:genetics / Q000378:metabolism; D013314:Stress, Mechanical
chemical_list: C508319:ACAN protein, human; D053674:Aggrecans; C546884:BGN protein, human; D058578:Biglycan; D024142:Collagen Type VI; D058575:Decorin; D055758:SOX9 Transcription Factor; C527932:SOX9 protein, human