A Chemically Defined Carrier for the Delivery of Human Mesenchymal Stem/Stromal Cells to Skin Wounds

Abstract

Skin has a remarkable capacity for regeneration, but age-and diabetes-related vascular problems lead to chronic non-healing wounds for many thousands of U.K. patients. There is a need for new therapeutic approaches to treat these resistant wounds. Donor mesenchymal stem/stromal cells (MSCs) have been shown to assist cutaneous wound healing by accelerating re-epithelialization. The aim of this work was to devise a low risk and convenient delivery method for transferring these cells to wound beds. Plasma polymerization was used to functionalize the surface of medical-grade silicone with acrylic acid. Cells attached well to these carriers, and culture for up to 3 days on the carriers did not significantly affect their phenotype or ability to support vascular tubule formation. These carriers were then used to transfer MSCs onto human dermis. Cell transfer was confirmed using an MTT assay to assess viable cell numbers and enhanced green fluorescent protein-labeled MSCs to demonstrate that the cells post-transfer attached to the dermis. We conclude that this synthetic carrier membrane is a promising approach for delivery of therapeutic MSCs and opens the way for future studies to evaluate its impact on repairing difficult skin wounds.

The Hematopoietic Chemokine CXCL12 Promotes Integration of Human Endothelial Colony Forming Cell–Derived Cells into Immature Vessel Networks

“…ECFC-derived cells from CB and human umbilical vein were prepared and cultured in complete EGM2 medium [35][36][37][38]. hDFs, human umbilical cord vein endothelial cells (HUVECs), and hBM MSCs were also sourced from Lonza Biologics and cultured as described [35][36][37][38].…”

“…ECFC-derived cells from CB and human umbilical vein were prepared and cultured in complete EGM2 medium [35][36][37][38]. hDFs, human umbilical cord vein endothelial cells (HUVECs), and hBM MSCs were also sourced from Lonza Biologics and cultured as described [35][36][37][38]. Typical immunophenotypes of these CB and HUVEC ECFC-derived cells and hBM MSCs have been described previously [35][36][37][38] and in Supplementary Fig.…”

“…hDFs, human umbilical cord vein endothelial cells (HUVECs), and hBM MSCs were also sourced from Lonza Biologics and cultured as described [35][36][37][38]. Typical immunophenotypes of these CB and HUVEC ECFC-derived cells and hBM MSCs have been described previously [35][36][37][38] and in Supplementary Fig. S1 (Supplementary Data are available online at www.liebertpub .com/scd).…”

“…Ex vivo assays have been developed to mimic human vessel formation either in fibrin or collagen gels [28][29][30][31][32][33][34][35][36][37]. These have combined endothelial cells or ECFCs with mural cells (eg, lung fibroblasts, dermal fibroblasts, retinal pericytes, or mesenchymal stromal cells) and specialized endothelial growth medium containing cytokines [eg, VEGF and fibroblast growth factor-2 (FGF-2)].…”

“…We have adapted our version of these in vitro models, in which human umbilical cord blood (CB) or umbilical cord (UC) ECFC-derived cells are cocultured with human dermal fibroblasts (hDFs) or human bone marrow mesenchymal stromal cells (hBM MSCs) in a 3D collagen type I sandwich assay in media containing VEGF and FGF-2 [34][35][36][37], by further developing a method to assess integration of exogenous human ECFC-derived cells into immature vascular tubule networks. Here, using this model together with timelapse microscopy and fluorescently tagged cells, we analyzed the effects of the AMD3100 antagonist on human vasculogenesis and angiogenesis and showed that AMD3100 not only inhibits the dynamic refinement of the vascular network in vitro by enhancing endothelial cell retraction but also modulates the incorporation of ECFC-derived cells into extant vascular networks.…”