PS186. Adipose-Derived Stem Cells from Diabetic Patients as Endothelial Cell Substitutes in Vascular Tissue Engineering

Abstract

strated a proapoptotic transcriptome. In vitro, ischemic AKI activated apoptosis (FasL,Dapk1,Bcl10) and TNF family (TNFR1,TNFR2,TNF␣) genes, caspase-3 (100 Ϯ 1.1 vs 106.5 Ϯ 0.8, P ϭ .00325), and PARP (10 Ϯ 3.5 vs 61.8 Ϯ 20.5, P ϭ .047) vs sham. Etanercept inhibited RLMVEC inflammatory genes (E-Selectin, ICAM-1, IL-6, RhoB), caspase-3 activity (100 Ϯ 0.9 vs 102 Ϯ 0.5, P ϭ .096) and PARP activity (10 Ϯ 2.3 vs 10.9 Ϯ 2.2, P ϭ .783) vs vehicle during ischemic AKI.Conclusions: Ischemic AKI drives a proinflammatory and proapoptotic lung EC transcriptome with TNFR1-dependent apoptosis. Further study of EC-specific mechanisms of kidney-lung crosstalk during AKI may identify potential therapeutic targets.Objectives: Surgical bypass and dialysis access creation are common procedures performed in diabetic patients. Only 45% of patients have autologous vascular tissue available for use as a conduit for these procedures. We have developed an alternative conduit composed of a vascular scaffold seeded with autologous adipose-derived stem cells (ASC) differentiated into endothelial cells (EC) to create a non-thrombogenic lumen. Herein, we examine ASC from diabetic (DM) versus non-diabetics (NDM) patients in terms of isolation efficiency, proliferation, commitment towards EC lineage, and seeding onto a vascular scaffold.Methods: ASC were isolated from peri-umbilical liposuction specimens by collagenase dispersion (DM nϭ53; NDM nϭ145). Isolation efficiency was defined by number of ASC isolated per gram of adipose tissue. Proliferation was assessed by constructing growth curves over 14d. ASC were differentiated in endothelial growth medium for 3wk. Differentiation was determined by measuring ECspecific gene expression (CD31, vWF) using qPCR. Lastly, ASC were seeded onto decellularized vein, flow conditioned from 0-9 dynes over 5d, and examined using confocal microscopy.Results: ASC isolation efficiency did not differ between DM and NDM patients (224,028 cells/gm vs. 259,345 cells/gm, respectively; P ϭ .21). The growth curves for DM (nϭ6) and NDM (nϭ6) ASC also appeared similar, with no significant differences observed in cells counts between days 1-14. After 1, 2, and 3wk in culture, no significant difference in CD31 or vWF expression between DM (nϭ6) and NDM (nϭ6) cells was observed. Finally, retention of ASC to vascular scaffolds under physiological shear stress was similar between the two groups.Conclusions: ASC are isolated from diabetics in quantities similar to non-diabetics. These cells grow at similar rates, exhibit differentiation into an EC phenotype, and line the lumen of a tissue engineered vascular graft.