RESUMO
Objective: Human amniotic membranes have been shown to be effective for healing diabetic foot ulcers clinically and to regulate stem cell activity in vitro and in vivo; however, diabetic stem cells may be impaired as a sequela of the disease. In this study, dehydrated human amnion/chorion membrane (dHACM) allografts (EpiFix®; MiMedx Group) were evaluated for their ability to regulate diabetic stem cells in vitro. Approach: Human adipose-derived stem cells (ADSCs) from normal, type I diabetic, and type II diabetic donors were treated with soluble extracts of dHACM and evaluated for proliferation after 3 days by DNA assay, chemotactic migration after 1 day by transwell assay, cytokine secretion after 3 days by multiplex ELISA, and gene expression after 5 days by reverse transcription-polymerase chain reaction. Results: Although diabetic ADSCs demonstrated decreased responses compared to normal ADSCs, dHACM treatment stimulated diabetic ADSCs to proliferate after 3 days and enhanced migration over 24 h, similar to normal ADSCs. dHACM-treated diabetic ADSCs modulated secretion of soluble signals, including regulators of inflammation, angiogenesis, and healing. All ADSCs evaluated also responded to dHACM treatment with altered expression of immunomodulatory genes, including interleukins (IL)-1α, IL-1ß, and IL-1RA. Innovation: This is the first reported case demonstrating that diabetic ADSCs respond to novel amniotic membrane therapies, specifically treatment with dHACM. Conclusion: dHACM stimulated diabetic ADSCs to migrate, proliferate, and alter cytokine expression suggesting that, despite their diabetic origin, ADSCs may respond to dHACM to accelerate diabetic wound healing.
RESUMO
Human-derived placental tissues have been shown in randomized clinical trials to be effective for healing chronic wounds, and have also demonstrated the ability to recruit stem cells to the wound site in vitro and in vivo. In this study, PURION(®) Processed dehydrated human amnion/chorion membrane allografts (dHACM, EpiFix(®) , MiMedx Group, Marietta, GA) were evaluated for their ability to alter stem cell activity in vitro. Human bone marrow mesenchymal stem cells (BM-MSCs), adipose derived stem cells (ADSCs), and hematopoietic stem cells (HSCs) were treated with soluble extracts of dHACM tissue, and were evaluated for cellular proliferation, migration, and cytokine secretion. Stem cells were analyzed for cell number by DNA assay after 24 h, closure of an acellular zone using microscopy over 3 days, and soluble cytokine production in the medium of treated stem cells was analyzed after 3 days using a multiplex ELISA array. Treatment with soluble extracts of dHACM tissue stimulated BM-MSCs, ADSCs, and HSCs to proliferate with a significant increase in cell number after 24 h. dHACM treatment accelerated closure of an acellular zone by ADSCs and BM-MSCs after 3 days, compared to basal medium. BM-MSCs, ADSCs, and HSCs also modulated endogenous production of a number of various soluble signals, including regulators of inflammation, mitogenesis, and wound healing. dHACM treatment promoted increased proliferation and migration of ADSCs, BM-MSCs, and HSCs, along with modulation of secreted proteins from those cells. Therefore, dHACM may impact wound healing by amplifying host stem cell populations and modulating their responses in treated wound tissues. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1495-1503, 2016.
