Poly(lactic-co-glycolic acid)/gelatin electrospun scaffolds seeded with human mesenchymal stem cells for skin tissue engineering

摘要

Introduction: Treatment options for burns are expensive and inaccessible to most people, so finding cheap to manufacture scaffolding materials is a priority. Materials of scaffolds must to promote adhesion, proliferation and cellular differentiation and finally, the generation of new tissues. Polylactic-co-glycolic acid (PLGA) and gelatin (GE) are materials that posses biocompatibility and biodegradability. Therefore, the aim of this study was to evaluate cell viability and biocompatibility of a PLGA/Ge scaffold seeded with human mesenchymal stem cells (HMSC) and implanted subcutaneously in mice. Materials and Methods: PLGA 18% (w/v) solution (LA/GA 50:50, Mw=54,000) and GE 10% (w/v) solution (from bovine skin) were prepared separately by dissolving both in 1,1,1,3,3,3-Hexafluoro-2-propanol (HFP) as solvent. Fibers were obtained from PLGA/GE 9:1 solution. Scaffolds were fabricated by electrospinning (flow rate: 0.3ml/hr, voltage: 10Kv and distance: 10cm). The hydrophobic was measured by contact angle method and the morphology was evaluated by SEM. HMSC's were isolated from Warthon jelly and stained with fluorescent cell tracker before were seeded on scaffolds. Viability cell were evaluated through LIVE/DEAD® Cell Viability Assays. After 5 days of culture, scaffolds containing HMSC's were implanted subcutaneously in Balb/c mice. Skin samples were obtained at 5,10,15 and 30 days. An immunofluorescent analysis and H&E staining were made. Results and Discussion: Scaffold fibers had an average thickness of 0.6nm and a hydrophilic surface with a contact angle of 39°. HMSC's seeded on scaffolds showed a viability of 95%. Due to the low porosity of the scaffolds (5μm), the cells were unable to migrate into the network, but remained viable with high confluence in the area where they were seeded. When scaffolds in murine skin were analyzed it was observed that HMSC's were viable and mouse fibroblasts colonized the scaffold. Granuloma lesions and epitheliod cells were observed, but Langhans cells were present. The data shown indicated that PLGA/GE scaffolds allowed cell viability in vitro and in vivo and promoted the migration of fibroblasts. Conclusion: PLGA/GE scaffolds showed to maintained viability and confluence cellular of HMSC's seeded on them during several days. Furthermore, scaffolds were biocompatible when were implanted in mice, so they can have potential utility as wound dressing in skin lesions.