Translational development of ABCB5+ dermal mesenchymal stem cells for therapeutic induction of angiogenesis in non-healing diabetic foot ulcers

Abstract

Background While rapid healing of diabetic foot ulcers (DFUs) is highly desirable to avoid infections, amputations and life-threatening complications, DFUs often respond poorly to standard treatment. GMP-manufactured skin-derived ABCB5+ mesenchymal stem cells (MSCs) might provide a new adjunctive DFU treatment, based on their remarkable skin wound homing and engraftment potential, their ability to adaptively respond to inflammatory signals, and their wound healing-promoting efficacy in mouse wound models and human chronic venous ulcers. Methods The angiogenic potential of ABCB5+ MSCs was characterized with respect to angiogenic factor expression at the mRNA and protein level, in vitro endothelial trans-differentiation and tube formation potential, and perfusion-restoring capacity in a mouse hindlimb ischemia model. Finally, the efficacy and safety of ABCB5+ MSCs for topical adjunctive treatment of chronic, standard therapy-refractory, neuropathic plantar DFUs were assessed in an open-label single-arm clinical trial. Results Hypoxic incubation of ABCB5+ MSCs led to posttranslational stabilization of the hypoxia-inducible transcription factor 1α (HIF-1α) and upregulation of HIF-1α mRNA levels. HIF-1α pathway activation was accompanied by upregulation of vascular endothelial growth factor (VEGF) transcription and increase in VEGF protein secretion. Upon culture in growth factor-supplemented medium, ABCB5+ MSCs expressed the endothelial-lineage marker CD31, and after seeding on gel matrix, ABCB5+ MSCs demonstrated formation of capillary-like structures comparable with human umbilical vein endothelial cells. Intramuscularly injected ABCB5+ MSCs to mice with surgically induced hindlimb ischemia accelerated perfusion recovery as measured by laser Doppler blood perfusion imaging and enhanced capillary proliferation and vascularization in the ischemic muscles. Adjunctive topical application of ABCB5+ MSCs onto therapy-refractory DFUs elicited median wound surface area reductions from baseline of 59% (full analysis set, n = 23), 64% (per-protocol set, n = 20) and 67% (subgroup of responders, n = 17) at week 12, while no treatment-related adverse events were observed. Conclusions The present observations identify GMP-manufactured ABCB5+ dermal MSCs as a potential, safe candidate for adjunctive therapy of otherwise incurable DFUs and justify the conduct of a larger, randomized controlled trial to validate the clinical efficacy. Trial registration: ClinicalTrials.gov, NCT03267784, Registered 30 August 2017, https://clinicaltrials.gov/ct2/show/NCT03267784

Mesenchymal stem cell-based therapy for non-healing wounds due to chronic limb-threatening ischemia: A review of preclinical and clinical studies

“…The use of autologous MSCs in clinical studies on diabetic CLTI patients have shown significant improvement in rates of overall wound healing (60,77). Lu et al have shown that over a longer period limb amputation rates were lower in the BM-MSC group compared to the BM-MNC group, and the ulcer recurrence rate in the BM-MSC group (29). Future studies should also examine similar MSC-based applications in CLTI patients with DM to ascertain whether similar beneficial effects for patients with DFU can be more broadly applied.…”

“…Treatment with gene-edited MSCs augmented blood perfusion and prevented limb loss in a murine model of hindlimb ischemia compared to unmodified MSCs due to the enhanced proangiogenic milieu induced by GCP-2 and SDF-1α-mediated upregulation of factors such as Angiopoietin 1 (Ang1) and VEGF ( 28 ). Kerstan et al utilized hypoxic incubation of skin-derived MSCs to induce upregulation of the transcription factor hypoxia-inducible transcription factor 1α (HIF-1α) ( 29 ). This further engaged canonical VEGF and angiogenic signaling pathways among MSCs to enhance capillary proliferation and vascularization in the ischemic muscle tissue of mice with hindlimb ischemia ( 29 ).…”

“…Kerstan et al utilized hypoxic incubation of skin-derived MSCs to induce upregulation of the transcription factor hypoxia-inducible transcription factor 1α (HIF-1α) ( 29 ). This further engaged canonical VEGF and angiogenic signaling pathways among MSCs to enhance capillary proliferation and vascularization in the ischemic muscle tissue of mice with hindlimb ischemia ( 29 ). Overall, continued preclinical studies to target postnatal angiogenesis with MSC therapy may provide future hope for clinical therapeutics to augment healing for patients with tissue gangrene and ischemic wounds.…”

“…Investigations on MSCs from Adipose Tissue (CeTMAd) are underway in a phase I/II trial (NCT01257776, NCT01745744; Table 1 ). Kerstan et al have recently completed a phase I/II randomized controlled trial, to test the safety of GMP-manufactured ABCB5 + dermal MSCs topical application to DFU (NCT03267784; Table 1 ) model after promising pre-clinical trials in the mouse model ( 29 ). Future studies should also examine similar MSC-based applications in CLTI patients with DM to ascertain whether similar beneficial effects for patients with DFU can be more broadly applied.…”

Small extracellular vesicles from mesenchymal stem cells: A potential Weapon for chronic non-healing wound treatment

“…MSCs have been frequently used and examined in clinic. For skin wound treatment, a series of clinical trials were performed to evaluate the efficacy of MSC application in serious skin burns ( Falanga et al, 2007 ), non-healing ulcers ( Dash et al, 2009 ; Li et al, 2013 ; Chen et al, 2018a ; Lu et al, 2019 ; Moon et al, 2019 ; Kerstan et al, 2021 ; Zhang et al, 2022a ; Kerstan et al, 2022 ) and advanced limb ischemia ( Yang et al, 2013 ; Lu et al, 2019 ). For example, Sheng et al first reported successful employment of MSCs to realize the regeneration of functional sweat glands in patients with deep burn injury ( Sheng et al, 2009 ).…”