title: Skin equivalent tensional force alters keloid fibroblast behavior and phenotype.
abstract: Skin tension may influence keloid scar behavior, development, and spreading, e.g., butterfly-shaped keloid disease in the sternum. Here, we developed a three-dimensional (3D) in vitro model to mimic in vivo tension and evaluate keloid fibroblast (KF) behavior and extracellular matrix synthesis under tension. In vivo skin tension measured in volunteers (n = 4) using 3D image photogrammetry enabled prediction of actual force (35 mN). A novel cell force monitor applied tension in a fibroblast-populated 3D collagen lattice replicating the in vivo force. The effect of tension on keloid (n = 10) fibroblast (KF) and normal skin (n = 10) fibroblasts (NF) at set time points (6, 12, and 24 hours) was measured in Hsp27, PAI-2, and α2β1 integrin, tension-related genes demonstrating significant (p < 0.05) time-dependent regulation of these genes in NF vs. KF with and without tension. KF showed higher (p < 0.05) proliferation post-tension. Knockdown of all three genes in 24 and 48 hours with and without tension showed significant down-regulation in NF vs. KF. Additionally, we show significant (p < 0.05) modification of the expression of extracellular matrix-related genes post-tension following down-regulation of Hsp27, PAI-2, or α2β1 integrin. Finally, we demonstrate significant alteration in NF compared with KF morphology following knockdown. In conclusion, this study shows induction of tension-related genes expression following mechano-regulation in KFs, with potential relevance to its development and therapy.
authors.affiliation: Plastic & Reconstructive Surgery Research, Manchester Institute of Biotechnology, University of Manchester, Manchester, United Kingdom; Bioengineering Group, School of Materials, University of Manchester, Manchester, United Kingdom.
authors.forename: Edna
authors.initials: E
authors.lastname: Suarez
authors.forename: Farhatullah
authors.initials: F
authors.lastname: Syed
authors.forename: Teresa A
authors.initials: TA
authors.lastname: Rasgado
authors.forename: Alan
authors.initials: A
authors.lastname: Walmsley
authors.forename: Parthasarathi
authors.initials: P
authors.lastname: Mandal
authors.forename: Ardeshir
authors.initials: A
authors.lastname: Bayat
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D005109:Extracellular Matrix / Q000378:metabolism; D005260:Female; D005347:Fibroblasts / Q000378:metabolism* / Q000473:pathology; D005786:Gene Expression Regulation; D055551:HSP27 Heat-Shock Proteins / Q000235:genetics* / Q000378:metabolism; D006360:Heat-Shock Proteins; D006801:Humans; D038982:Integrin alpha2beta1 / Q000235:genetics* / Q000378:metabolism; D007627:Keloid / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D008297:Male; D008875:Middle Aged; D018832:Molecular Chaperones; D017396:Plasminogen Activator Inhibitor 2 / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013314:Stress, Mechanical; D014945:Wound Healing / Q000235:genetics* / Q000502:physiology; D055815:Young Adult
chemical_list: D055551:HSP27 Heat-Shock Proteins; C057725:HSPB1 protein, human; D006360:Heat-Shock Proteins; D038982:Integrin alpha2beta1; D018832:Molecular Chaperones; D017396:Plasminogen Activator Inhibitor 2; D012333:RNA, Messenger