title: Decellularized silk fibroin scaffold primed with adipose mesenchymal stromal cells improves wound healing in diabetic mice.
abstract: BACKGROUND
  Silk fibroin (SF) scaffolds have been shown to be a suitable substrate for tissue engineering and to improve tissue regeneration when cellularized with mesenchymal stromal cells (MSCs). We here demonstrate, for the first time, that electrospun nanofibrous SF patches cellularized with human adipose-derived MSCs (Ad-MSCs-SF), or decellularized (D-Ad-MSCs-SF), are effective in the treatment of skin wounds, improving skin regeneration in db/db diabetic mice.
  
  
  METHODS
  The conformational and structural analyses of SF and D-Ad-MSCs-SF patches were performed by scanning electron microscopy, confocal microscopy, Fourier transform infrared spectroscopy and differential scanning calorimetry. Wounds were performed by a 5 mm punch biopsy tool on the mouse's back. Ad-MSCs-SF and D-Ad-MSCs-SF patches were transplanted and the efficacy of treatments was assessed by measuring the wound closure area, by histological examination and by gene expression profile. We further investigated the in vitro angiogenic properties of Ad-MSCs-SF and D-Ad-MSCs-SF patches by affecting migration of human umbilical vein endothelial cells (HUVECs), keratinocytes (KCs) and dermal fibroblasts (DFs), through the aortic ring assay and, finally, by evaluating the release of angiogenic factors.
  
  
  RESULTS
  We found that Ad-MSCs adhere and grow on SF, maintaining their phenotypic mesenchymal profile and differentiation capacity. Conformational and structural analyses on SF and D-Ad-MSCs-SF samples, showed that sterilization, decellularization, freezing and storing did not affect the SF structure. When grafted in wounds of diabetic mice, both Ad-MSCs-SF and D-Ad-MSCs-SF significantly improved tissue regeneration, reducing the wound area respectively by 40% and 35%, within three days, completing the process in around 10 days compared to 15-17 days of controls. RT2 gene profile analysis of the wounds treated with Ad-MSCs-SF and D-Ad-MSCs-SF showed an increment of genes involved in angiogenesis and matrix remodeling. Finally, Ad-MSCs-SF and D-Ad-MSCs-SF co-cultured with HUVECs, DFs and KCs, preferentially enhanced the HUVECs' migration and the release of angiogenic factors stimulating microvessel outgrowth in the aortic ring assay.
  
  
  CONCLUSIONS
  Our results highlight for the first time that D-Ad-MSCs-SF patches are almost as effective as Ad-MSCs-SF patches in the treatment of diabetic wounds, acting through a complex mechanism that involves stimulation of angiogenesis. Our data suggest a potential use of D-Ad-MSCs-SF patches in chronic diabetic ulcers in humans.
authors.forename: Stefania Elena
authors.initials: SE
authors.lastname: Navone
authors.forename: Luisa
authors.initials: L
authors.lastname: Pascucci
authors.forename: Marta
authors.initials: M
authors.lastname: Dossena
authors.forename: Anna
authors.initials: A
authors.lastname: Ferri
authors.forename: Gloria
authors.initials: G
authors.lastname: Invernici
authors.forename: Francesco
authors.initials: F
authors.lastname: Acerbi
authors.forename: Silvia
authors.initials: S
authors.lastname: Cristini
authors.forename: Gloria
authors.initials: G
authors.lastname: Bedini
authors.forename: Valentina
authors.initials: V
authors.lastname: Tosetti
authors.forename: Valentina
authors.initials: V
authors.lastname: Ceserani
authors.forename: Arianna
authors.initials: A
authors.lastname: Bonomi
authors.forename: Augusto
authors.initials: A
authors.lastname: Pessina
authors.forename: Giuliano
authors.initials: G
authors.lastname: Freddi
authors.forename: Antonio
authors.initials: A
authors.lastname: Alessandrino
authors.forename: Piero
authors.initials: P
authors.lastname: Ceccarelli
authors.forename: Rolando
authors.initials: R
authors.lastname: Campanella
authors.forename: Giovanni
authors.initials: G
authors.lastname: Marfia
authors.forename: Giulio
authors.initials: G
authors.lastname: Alessandri
authors.forename: Eugenio Agostino
authors.initials: EA
authors.lastname: Parati
mesh_terms: D000273:Adipose Tissue / Q000166:cytology; D000818:Animals; D002448:Cell Adhesion; D002465:Cell Movement; D049109:Cell Proliferation; D002478:Cells, Cultured; D005347:Fibroblasts / Q000502:physiology; D005349:Fibroins / Q000494:pharmacology*; D061307:Human Umbilical Vein Endothelial Cells / Q000502:physiology; D006801:Humans; D015603:Keratinocytes / Q000502:physiology; D045164:Mesenchymal Stem Cell Transplantation / Q000379:methods*; D059630:Mesenchymal Stem Cells / Q000166:cytology* / Q000187:drug effects / Q000502:physiology; D051379:Mice; D008820:Mice, Obese; D018919:Neovascularization, Physiologic; D051381:Rats; D017207:Rats, Sprague-Dawley; D062326:Re-Epithelialization; D054411:Receptors, Leptin / Q000235:genetics; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D054411:Receptors, Leptin; C482288:fibroin, silkworm; C515447:leptin receptor, mouse; D005349:Fibroins