title: Integrin-mediated adhesion and proliferation of human MSCs elicited by a hydroxyproline-lacking, collagen-like peptide.
abstract: In this study, we evaluated the competence of a rationally designed collagen-like peptide (CLP-Cys) sequence - containing the minimal essential Glycine-Glutamic acid-Arginine (GER) triplet but lacking the hydroxyproline residue - for supporting human mesenchymal stem cell (hMSC) adhesion, spreading and proliferation. Cellular responses to the CLP-Cys sequence were analyzed by conjugating the peptide to two different substrates - a hard, planar glass surface and a soft hyaluronic acid (HA) particle-based hydrogel. Integrin-mediated cell spreading and adhesion were observed for hMSCs cultivated on the CLP-Cys functionalized surfaces, whereas on control surfaces lacking the peptide motif, cells either did not adhere or maintained a round morphology. On the glass surface, CLP-Cys-mediated spreading led to the formation of extended and well developed stress fibers composed of F-actin bundles and focal adhesion complexes while on the soft gel surface, less cytoskeletal reorganization organization was observed. The hMSCs proliferated significantly on the surfaces presenting CLP-Cys, compared to the control surfaces lacking CLP-Cys. Competitive binding assay employing soluble CLP-Cys revealed a dose-dependent inhibition of hMSC adhesion to the CLP-Cys-presenting surfaces. Blocking the α(2)β(1) receptor on hMSC also resulted in a reduction of cell adhesion on both types of CLP-Cys surfaces, confirming the affinity of CLP-Cys to α(2)β(1) receptors. These results established the competence of the hydroxyproline-free CLP-Cys for eliciting integrin-mediated cellular responses including adhesion, spreading and proliferation. Thus, CLP-Cys-modified HA hydrogels are attractive candidates as bioactive scaffolds for tissue engineering applications.
authors.affiliation: Department of Materials Science and Engineering, University of Delaware, Newark, DE 19716, USA.
authors.forename: Ohm D
authors.initials: OD
authors.lastname: Krishna
authors.forename: Amit K
authors.initials: AK
authors.lastname: Jha
authors.forename: Xinqiao
authors.initials: X
authors.lastname: Jia
authors.forename: Kristi L
authors.initials: KL
authors.lastname: Kiick
mesh_terms: D002448:Cell Adhesion / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002942:Circular Dichroism; D003094:Collagen / Q000494:pharmacology*; D003599:Cytoskeleton / Q000187:drug effects / Q000378:metabolism; D005450:Fluorescamine / Q000378:metabolism; D005455:Fluorescent Antibody Technique; D022001:Focal Adhesions / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D018960:Hyaluronan Receptors / Q000378:metabolism; D006909:Hydroxyproline / Q000172:deficiency*; D038982:Integrin alpha2beta1 / Q000378:metabolism*; D059630:Mesenchymal Stem Cells / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D008856:Microscopy, Fluorescence; D009942:Organometallic Compounds / Q000378:metabolism; D009943:Organophosphorus Compounds / Q000378:metabolism; D010455:Peptides / Q000494:pharmacology*; D011487:Protein Conformation; D012995:Solubility / Q000187:drug effects; D013194:Staining and Labeling
chemical_list: D018960:Hyaluronan Receptors; D038982:Integrin alpha2beta1; D009942:Organometallic Compounds; D009943:Organophosphorus Compounds; D010455:Peptides; C066850:Cascade Blue; D005450:Fluorescamine; D003094:Collagen; D006909:Hydroxyproline