Human iPSCs-derived mesenchymal stem cells promote skin regeneration and burn wound healing

Abstract

The key to surviving severe burns is rapid burn wound excision and closure, yet extensive wounds often surpass natural healing capacity. Alternative treatments, such as synthetic skin substitutes, have not emerged as a standard, optimal solution. Stem cell therapies, especially using allogenic sources, show promise in enhancing wound repair. Induced mesenchymal stem cells (iMSCs) have demonstrated vast possibilities to overcome traditional stem cell therapy limitations. This study utilized Cord tissue-derived iMSCs (CT-iMSCs) incorporated into well-established epidermal-dermal substitutes Integra® Dermal Regeneration Template (DRT) at 5000-20,000 cells/cm² in a porcine full-thickness burn model to test their regenerative capabilities. We evaluated healing outcomes, inflammation, neovascularization, collagen levels, and fibrosis markers. Wounds treated with CT-iMSCs showed notable improvements, including faster wound healing, better epithelialization, and marked improvements in healing markers compared to controls. These data support the potential of iMSCs as an ideal cell source for autologous skin regeneration.

Fig. 1. Schematic illustration depicting the study workflow.

Isolated human CT-MSCs were reprogrammed to CT-iPSCs and further differentiated to iMSCs. These were expanded and seeded onto Integra DRT for application and testing in our porcine thermal injury model. Created with BioRender.com.

Fig. 2. Characterization of the induced Mesenchymal stem cells (iMSCs).

A Flow cytometry plot showing cell-positive expression of multipotency markers. CD105 + /CD4- cells were gated and sorted. Then, CD105+ cells were gated for CD73+ and CD90 + . B Bright field image showing the morphological changes of CT-iPSCs from round, in colony appearance, to spindle-shaped iMSCs. C Differentiated iMSCs exhibit multilineage differentiation capacity: Chondroblast (Alcian-Blue), Adipocyte (oil-Red-O), and Osteoblasts (Alizarin Red).

Fig. 3. iMSCs improve the quality of wound healing.

A Macroscopic images of wounds on days 32 and 40 post-burn. On day 32, iMSCs-treated wounds exhibited complete wound closure, by day 32 while both control and acellular Integra groups still showed open wounds. By Day 40, all wounds showed complete closure. Black lines represent the initial dimensions of the excised wounds. B, C Statistical analysis of rate and the total amount of neo-epithelization, 10 K/cm² iMSCS showed the highest levels compared to control groups. D simulated wound map displaying wound edge contraction. E Wound contracture rate analysis. iMSCs 5 and 10 K/cm² show the lowest contraction. F Vancouver scar scale scoring, control wounds showed a slight, nonsignificant increase compared to the iMSCS-treated wound. Data is representative of three independent experiments (N = 3). Data presented as mean ± SEM, P * < 0.05, ** < 0.005, N = 3.

Fig. 4. iMSCs treatment restores skin histological features.

A Histological sections from healing wounds stained for H&E (Upper panel scale bar= 200 µm) (Lower panel scale bar= 50 µm). and (B) Mason’s trichrome (Upper panel scale bar= 500 µm) (Lower panel scale bar= 200 µm). C Statistical analysis of average epidermis thickness. D Statistical analysis of the average number rete ridges per 1 mm E Statistical analysis of average collagen deposition. Data is representative of three independent experiments (N = 3). Data presented as ± SEM, P *** <0.0005, **** <0.0001.

Fig. 5. iMSCs modulation of wound healing markers.

A–D iMSCs treatment suppresses major proinflammatory mediators (A) IL1β, (B) TNF-α, (C) IL6, and (D) TGFβ3. E, F iMSCs-treated wounds showed a marked increase in Coll1 deposition (E) and a slight or no increase in Coll3 (F). G, H Matrix Metalloproteinases (MMPs), MMP-2 expressions were elevated significantly in 5 and 20 K/cm² iMSCs groups (G), while MMP-9 was reduced in all treatment groups. Data is representative of three independent experiments (N = 3). Data is presented as mean ± SEM, P * <0.05, ** <0.005, *** <0.0005,**** <0.0001.