ABSTRACT
OBJECTIVE: We investigated the association between the functional, epigenetic, and expressional profile of human adventitial progenitor cells (APCs) and therapeutic activity in a model of limb ischemia. APPROACH AND RESULTS: Antigenic and functional features were analyzed throughout passaging in 15 saphenous vein (SV)-derived APC lines, of which 10 from SV leftovers of coronary artery bypass graft surgery and 5 from varicose SV removal. Moreover, 5 SV-APC lines were transplanted (8×10(5) cells, IM) in mice with limb ischemia. Blood flow and capillary and arteriole density were correlated with functional characteristics and DNA methylation/expressional markers of transplanted cells. We report successful expansion of tested lines, which reached the therapeutic target of 30 to 50 million cells in ≈10 weeks. Typical antigenic profile, viability, and migratory and proangiogenic activities were conserved through passaging, with low levels of replicative senescence. In vivo, SV-APC transplantation improved blood flow recovery and revascularization of ischemic limbs. Whole genome screening showed an association between DNA methylation at the promoter or gene body level and microvascular density and to a lesser extent with blood flow recovery. Expressional studies highlighted the implication of an angiogenic network centered on the vascular endothelial growth factor receptor as a predictor of microvascular outcomes. FLT-1 gene silencing in SV-APCs remarkably reduced their ability to form tubes in vitro and support tube formation by human umbilical vein endothelial cells, thus confirming the importance of this signaling in SV-APC angiogenic function. CONCLUSIONS: DNA methylation landscape illustrates different therapeutic activities of human APCs. Epigenetic screening may help identify determinants of therapeutic vasculogenesis in ischemic disease.
Subject(s)
Adventitia/transplantation , DNA Methylation , Epigenesis, Genetic , Ischemia/surgery , Muscle, Skeletal/blood supply , Neovascularization, Physiologic , Saphenous Vein/transplantation , Stem Cell Transplantation , Stem Cells/physiology , Adventitia/cytology , Animals , Blood Flow Velocity , Cell Movement , Cell Proliferation , Cell Survival , Cells, Cultured , Disease Models, Animal , Gene Expression Profiling/methods , Hindlimb , Human Umbilical Vein Endothelial Cells/physiology , Humans , Ischemia/genetics , Ischemia/physiopathology , Mice , Neovascularization, Physiologic/genetics , Recovery of Function , Regional Blood Flow , Saphenous Vein/cytology , Stem Cells/metabolism , Time FactorsABSTRACT
In this study, we present an inexpensive and effective method for providing a secure and hemostatic anastomosis using autologous adventitia obtained from a dissected or aneurysmal wall. The resected aortic wall is separated between the adventitia and media, and a soft, 2 × 10-cm adventitial strip is overlaid to cover the anastomotic margin. A graft is sutured to the aortic stump. This autologous adventitial overlay method can inexpensively and strongly reinforce the anastomosis during aortic surgery for dissection or aneurysm and will contribute to anastomotic hemostasis and long-term stability.
Subject(s)
Adventitia/transplantation , Aortic Aneurysm, Thoracic/surgery , Aortic Dissection/surgery , Blood Vessel Prosthesis Implantation/methods , Anastomosis, Surgical/methods , Graft Survival , Humans , Suture Techniques , Tensile Strength , Transplantation, Autologous , Tunica Media/surgeryABSTRACT
BACKGROUND: Periosteal adventitia is believed to consist of fibrous tissue without any regenerative potential. This theory results in the assumption that surgically stripped periosteum which is also adventitial has no bone regeneration potential. We decided to test whether the periosteal adventitia is osteoinductive and whether it is suitable for a commonly faced clinical situation in an animal model. METHODS: This study used 24 femurs from 12 rabbits, which were separated into 3 groups. Lateral femoral condylar cavitary defects were created with a 5 mm drill bit. In group I, the defects were left empty as the control. In group II, the defects were only filled with ceramic graft particles. In group III, the defects were filled with a mixture of ceramic graft particles and autogenous, adventitial, periosteal particles. All animals were sacrificed at the end of the 6th week and were evaluated histologically. RESULTS: The microscopy of 3 different histologists suggested that group III had far superior healing when compared to the control group and group II. The statistical evaluation of the histomorphometrically gathered quantitative results revealed a meaningful increase in woven bone and a decrease in fibrous tissue in group III, confirming the histological analysis. CONCLUSIONS: In this study we observed that the composite graft obtained by mixing ceramics and free adventitial periosteal grafts offers healing potential surpassing both the ceramic-only group as well as the control group. We conclude that adventitial periosteal graft greatly facilitates new bone formation.
