Allogeneic Adipose-Derived Mesenchymal Stem Cell Transplantation Enhances the Expression of Angiogenic Factors in a Mouse Acute Hindlimb Ischemic Model

Microporous Biodegradable Films Promote Therapeutic Angiogenesis

Peripheral arterial disease and critical limb ischemia are common symptoms of cardiovascular disease. Vascular surgery is used to create a bypass around occluded blood vessels to improve blood flow to ischemic muscle, thus avoiding the need for amputation. Attempts to vascularize tissues by therapeutic angiogenesis using delivery of exogenous angiogenic agents are underwhelming. A material-based approach that provides an endogenous stimulus capable of promoting angiogenesis and increased tissue perfusion would provide a paradigm shift in treatment options available. It is reported here that microporous biodegradable films produced using thermally induced phase separation provide a localized biophysical stimulus of proangiogenic genes in vivo that is associated with increased blood vessel density and restoration of blood flow to ischemic tissue. These findings show, for the first time, that acellular, nonfunctionalized biodegradable biomaterials can provide an innovative, material-based approach for therapeutic angiogenesis to enhance tissue reperfusion in vivo.

In Vitro Production of Cartilage Tissue from Rabbit Bone Marrow-Derived Mesenchymal Stem Cells and Polycaprolactone Scaffold

In vitro production of tissues or tissue engineering is a promising approach to produce artificial tissues for regenerative medicine. There are at least three important components of tissue engineering, including stem cells, scaffolds and growth factors. This study aimed to produce cartilage tissues in vitro from culture and chondrogenic differentiation of rabbit bone marrow-derived mesenchymal stem cells (BMMSCs), induced by chondrogenesis medium, on biodegradable polycaprolactone (PCL) scaffolds. BMMSCs were isolated from rabbit bone marrow according to the standard protocol. The adherence, proliferation and differentiation of BMMSCs on scaffolds were investigated using two scaffold systems: PCL scaffolds and collagen-coated PCL (PCL/col) scaffolds. The results showed that BMMSCs could attach and grow on both PCL and PCL/col scaffolds. However, the adhesion efficacy of BMMSCs on the PCL/col scaffolds was significantly better than on PCL scaffolds. Under induced conditions, BMMSCs on PLC/col scaffolds showed increased aggrecan accumulation and upregulated expression of chondrogenesis-associated genes (e.g. collagen type II, collagen type I, aggrecan and collagen type X) after 3, 7, 21 and 28 days of induction. These in vitro cartilage tissues could form mature chondrocyte-like cells after they were grafted into rabbits. The results suggest that use of BMMSCs in combination with polycaprolactone scaffolds and chondrogenesis medium can be a way to form in vitro cartilage tissue.