The Use of Adipose Mesenchymal Stem Cells and Human Umbilical Vascular Endothelial Cells on a Fibrin Matrix for Endothelialized Skin Substitute

Abstract

In recent years, the reconstruction of human skin by tissue engineering represents a clinical challenge and has offered a therapeutic alternative. Avascular engineered skin equivalents have been available for several years and used to treat wounds due to burns, nonhealing ulcers, and surgical excisions. They are constituted by different types of cultured cells included in a three-dimensional structure that permits cellular proliferation to create tissue substitutes. The major drawback of these artificial skin substitutes is their lack of blood supply, since the endurance and cell proliferation of the substitute depend on an adequate oxygen and nutrient supply and on toxin removal. These functions are served by the vascular system. We have produced a new model of endothelialized skin substitute that promotes the formation of capillary-like structures by seeding human umbilical vein endothelial cells (HUVECs) with dermal fibroblasts and human adipose-derived mesenchymal stem cells (hADMSCs) in a fibrin matrix. Dermal fibroblasts and hADMSCs produce extracellular matrix that stimulates cellular growth and proliferation. hADMSCs secrete significant quantities of angiogenic and antiapoptotic factors (vascular endothelial growth factor and hepatocyte growth factor), which induce in vitro differentiation of these cells into endothelial cells promoting angiogenesis and participating in tissue repair and skin regeneration processes. We obtained the artificial skin substitute with similar structure to native skin, including dermis and epidermis. We demonstrated that endothelial cells (CD31 and von Willebrand factor positive) proliferated and organized themselves into capillary-like structures within the fibrin matrix. The epidermis showed a complete epithelization by squamous cells (AE1/AE3 cytokeratin positive) with intracytoplasmic keratohyalin granules, hyperkeratosis, and parakeratosis. We have established a novel artificial skin substitute that facilitates the formation of capillary-like structures that may provide a novel therapeutic approach to different skin defects and prove to be a useful tool for regenerative medicine.

Hypoxic Signaling During Tissue Repair and Regenerative Medicine

“…It is thought that the usage of autologous stem cells could be beneficial for repairing or regenerating injured tissues. Recently, Sánchez Muñoz et al [ 124 ] showed in an artificial skin substitute model of fibroblasts and keratinocytes embedded in a fibrin matrix that capillary-like structures were only formed when human umbilical cord endothelial cells were implanted in the fibrin matrix in combination with human adipose-derived mesenchymal stem cells. These capillary-like structures were lined with CD31 + and vWF + cells, suggesting that these lining cells are endothelial cells.…”

Enhancing repair of full-thickness excisional wounds in a murine model: Impact of tissue-engineered biological dressings featuring human differentiated adipocytes

“…More recently, mesenchymal stem cell-based therapies have emerged as promising strategies to promote skin wound healing in light of the therapeutic effects associated with their important secretion of potent soluble mediators. In particular, human ASCs have been used for in vitro engineering of skin [46][47][48] or dermal/connective tissue substitutes [18-20, 49, 50] that are relevant either as permanent replacement tissues or as substitutes stimulating endogenous cell repair mechanisms.…”

Mesenchymale Stromazellen auf dem Weg zur klinischen Anwendung: Update 2018

“…MSCs exprimieren eine Vielzahl von Faktoren, z. B. basic fibroblast growth factor (bFGF), vascular endothelial growth factor A (VEGF-A) und Adrenomedullin, die unter anderem Endothelzellen zur Teilung anregen und die Bildung eines langfristig funktionierenden vaskulären Netzwerks fördern [49,50]. Darüber hinaus regen die sezernierten Faktoren die Proliferation und Migration von Keratinozyten und dermalen Fibroblasten an, diese Eigenschaft kann jedoch bei Patienten mit chronischen Wunden gestört sein [51,52].…”