Mesenchymal stromal cell‐derived factors promote the colonization of collagen 3D scaffolds with human skin cells

Abstract

The development of stem cell technology in combination with advances in biomaterials has opened new ways of producing engineered tissue substitutes. In this study, we investigated whether the therapeutic potential of an acellular porous scaffold made of type I collagen can be improved by the addition of a powerful trophic agent in the form of mesenchymal stromal cells conditioned medium (MSC‐CM) in order to be used as an acellular scaffold for skin wound healing treatment. Our experiments showed that MSC‐CM sustained the adherence of keratinocytes and fibroblasts as well as the proliferation of keratinocytes. Moreover, MSC‐CM had chemoattractant properties for keratinocytes and endothelial cells, attributable to the content of trophic and pro‐angiogenic factors. Also, for the dermal fibroblasts cultured on collagen scaffold in the presence of MSC‐CM versus serum control, the ratio between collagen III and I mRNAs increased by 2‐fold. Furthermore, the gene expression for α‐smooth muscle actin, tissue inhibitor of metalloproteinase‐1 and 2 and matrix metalloproteinase‐14 was significantly increased by approximately 2‐fold. In conclusion, factors existing in MSC‐CM improve the colonization of collagen 3D scaffolds, by sustaining the adherence and proliferation of keratinocytes and by inducing a pro‐healing phenotype in fibroblasts.

Human Mesenchymal Stromal Cell-Derived Exosomes Promote In Vitro Wound Healing by Modulating the Biological Properties of Skin Keratinocytes and Fibroblasts and Stimulating Angiogenesis

“…As shown in Figure 4C, after 4 h of incubation, PKH67-labeled exosomes were readily taken up by the dermal fibroblasts. In a previous study [7], our group obtained similar results for complete MSC-derived conditioned medium, suggesting that this is a characteristic of the whole MSC secretome. showing the uptake of PKH67-labeled exosomes by dermal fibroblasts.…”

“…In recent years, the therapeutic application of bone marrow-derived mesenchymal stromal/stem cells (MSCs) shifted from cellular transplantation to acellular therapy, in light of a novel mechanism of action, based on the favorable effects of factors secreted by these cells. Previous work, including our own, supports the use of MSC conditioned medium (CM) for skin wound healing, on account of its stimulative properties on several key biological processes such as proliferation, migration, and angiogenesis [4][5][6][7][8][9]. Besides growth factors and cytokines, the CM (the secretome) also includes the ubiquitous large family of extracellular vesicles (EVs) comprising exosomes, microvesicles (microparticles), and apoptotic bodies.…”

“…Among others, the focus centers on the mesenchymal stromal cells-derived exosomes as the main effectors of the paracrine activity exerted by these cells. In a previous study, we have reported MSC secretome to be relevant for skin wound healing by promoting colonization of collagen scaffolds [7]. Since little is known about the particular secretome components that influence the process of wound healing, we set up a series of experiments to investigate the specific role of exosomes in this process, in particular during the main phases of the skin healing process: inflammation, proliferation, and maturation.…”

“…Human MSC and dermal fibroblasts were isolated after informed consent with the approval of the Institutional Ethical Committee (180/27 September 2018), in accordance with the most recent version of the Helsinki declaration of World Medical Association (Ethical Principles for Medical Research Involving Human Subjects, October 2008). The cells were characterized as previously described [7]. Both cell types were plated at 10 4 cell/cm 2 and grown in DMEM 1 g/L glucose supplemented with 1% non-essential amino acids (Sigma Aldrich, St. Louis, MO, USA), 10% fetal bovine serum (FBS), 1% penicillin, streptomycin and neomycin, at 37 • C and 5% CO 2 .…”

Use of confocal microscopy imaging for in vitro assessment of adipose‐derived mesenchymal stromal cells seeding on acellular dermal matrices: 3D reconstruction based on collagen autofluorescence

“…Many authors already proved MSC ability to secrete proepithelizing mediators and recently MSC‐derived factors have also been shown to promote the colonization of collagen‐based 3D scaffolds with human skin cells 24 . Latter data seem to confirm this role for MSC‐CM in promoting the adherence of keratinocytes and fibroblasts as well as keratinocyte proliferation in collagen‐based scaffolding materials 42 . Those studies also demonstrated the induction of a prohealing phenotype in fibroblasts cultured on collagen scaffold in the presence of MSC‐CM.…”