Abstract 16685: Induced Pluripotent Stem Cell Based Drug Screening Platform for Vascular Abnormalities in Patients With Elastin Insufficiency
Elastin haploinsufficiency (EI), a rare disorder, is characterized by vascular smooth muscle cell (SMC) hyper-proliferation and arterial stenoses for which no therapies exist. We developed a high throughput assay using induced pluripotent stem cell (iPSC) derived SMCs from EI patients. The objective was to perform candidate drug screens to find drugs that can rescue the abnormal SMC phenotype.
Methods: Reprogrammed iPSCs from 3 patients with 7q11.23 deletion (WBS), 2 patients with single gene mutation in elastin, and 2 healthy controls were differentiated into SMCs and treated with either DMSO, rapamycin or its analogs, calcium channel blockers, or drugs known to induce elastogenesis (n=15 drugs). Assays included (i) high content fluorescence imaging for SMC differentiation marker, SM22α; (ii) SMC proliferation using XCELLigence platform; (iii) and contraction force measurements with endothelin in 3D bioengineered SMC tissues to assess functional maturation. Results were compared between drug vs DMSO-treated cells.
Results: Control iPSCs yielded 80-90% SM22α positive SMCs that were functionally mature i.e. showed contractile response to endothelin. Compared to controls, WBS-SMCs showed a 1.5 fold lower SM22α expression (p=0.02), 4 fold higher proliferation (p=0.01), and no response to endothelin. Rapamycin increased SM22α expression (green color, Fig 1). In addition, 5 drugs from 2 classes increased SM22α expression in WBS-SMCs by 1.3-1.4 fold (p<0.05 vs DMSO). The drugs also reduced WBS-SMC proliferation by 1.3-2.8 fold and are being tested in 3D tissues for effect on contractility.
Conclusion: The human iPSC-SMC based screening assay can identify drug classes that have beneficial effects in SMCs from EI patients. This platform can be used to screen drug libraries to identify the most effective drug in each drug class with the least toxicity that may eventually be useful for treatment using a drug repurposing approach.
Author Disclosures: C. Kinnear: None. R. Agrawal: None. C. Loo: None. A. Pahnke: None. T. Thompson: None. D. de Carvalho Rodrigues: None. M. Radisic: None. J. Ellis: None. S. Mital: None.
- © 2016 by American Heart Association, Inc.