MSCs seeded on bioengineered scaffolds improve skin wound healing in rats.

Growing evidence has shown the promise of mesenchymal stromal cells (MSCs) for the treatment of cutaneous wound healing. We have previously demonstrated that MSCs seeded on an artificial dermal matrix, Integra (Integra Lifesciences Corp., Plainsboro, NJ) enriched with platelet-rich plasma (Ematrix) have enhanced proliferative potential in vitro as compared with those cultured on the scaffold alone. In this study, we extended the experimentation by evaluating the efficacy of the MSCs seeded scaffolds in the healing of skin wounds in an animal model in vivo. It was found that the presence of MSCs within the scaffolds greatly ameliorated the quality of regenerated skin, reduced collagen deposition, enhanced reepithelization, increased neo-angiogenesis, and promoted a greater return of hair follicles and sebaceous glands. The mechanisms involved in these beneficial effects were likely related to the ability of MSCs to release paracrine factors modulating the wound healing response. MSC-seeded scaffolds, in fact, up-regulated matrix metalloproteinase 9 expression in the extracellular matrix and enhanced the recruitment of endogenous progenitors during tissue repair. In conclusion, the results of this study provide evidence that the treatment with MSC-seeded scaffolds of cutaneous wounds contributes to the recreation of a suitable microenvironment for promoting tissue repair/regeneration at the implantation sites.

Dermal matrix scaffold engineered with adult mesenchymal stem cells and platelet-rich plasma as a potential tool for tissue repair and regeneration.

The purpose of this study was to investigate the efficacy of Integra, an artificial dermal matrix used as a dermal template for skin regeneration, to form a multifunctional scaffold with human bone marrow-derived mesenchymal stem cells (hMSCs) and platelet-rich plasma (PRP) for tissue engineering and regenerative technology. First, we showed that PRP, used as a supplement for growth medium, represented an optimal substitute for animal serum as well as a source of multiple growth factors, was able to satisfactorily support cell viability and cell proliferation and influence stemness gene expression in hMSCs. Moreover, Integra appeared to be a suitable substrate for hMSCs colonization, as judged by two-photon microscopy combined with fluorescence lifetime imaging (FLIM) and confocal analysis. The cells were then seeded on Integra + PRP for 24 and 48 h. Notably, in these conditions, the seeded cells exhibited a greater aptitude to colonize the scaffold, showed improved cell adhesion and spreading as compared with those cultured on Integra alone, and acquired a fibroblast-like phenotype, indicating that the bioengineered scaffold provided an appropriate environment for cellular growth and differentiation. In conclusion, these results, although preliminary, provide clues for the design of new therapeutic strategies for skin regeneration, consisting in the combination of mesenchymal stem cells with engineered biomaterials.

Hemodynamic 3D Infrared Thermal Stereoscopic Imaging (TSI) Investiga- tion in Chronic Vascular Leg Ulcers: A Feasibility Study.

UNLABELLED: Hemodynamic 3D infrared thermal stereoscopic imaging (TSI) was tested as a new non-invasive diagnostic method for studying chron- ic vascular leg ulcers. The aim was to test this new diagnostic approach in investigating mixed arterio-venous wounds. Duplex ultrasonography is the most useful test for investigating hemodynamic alterations in patients with vascular cutaneous ulcers; however, it fails to provide any information about microvascular dysfunctions, which could play a sig- nificant role in the development of skin wounds. The study of thermal patterns at the wound site represents a method of investigating cu- taneous microcirculation-temperature gradients indicating abnormal blood flow in the margins and bed of wounds with vascular disorders are well correlated with clinical findings. METHODS: In order to evaluate the predominance of the arterial or venous component in vascular mixed ulcers of the leg and to understand the underlying pathology of the ulcers, 3D thermography was tested in three different hemodynamic positions. A total of 20 physiological and 20 pathological patients were assessed standing, supine, or in a discharging position (legs raised above heart level). RESULTS: A relatively constant temperature trend was observed in healthy subjects, while a different reaction was recorded in those with ulcerated legs. Moreover, a different temperature trend was noted among the varying hemodynamic positions and a trend differ- ence was also observed between arterial and venous ulcers in clinical investigation tests. CONCLUSION: TSI appears to be a safe, user-friendly, rapid, and promising procedure for distinguishing both arterial and ve- nous involvement in mixed arterio-venous leg ulcers. .