Abstract 12515: Enhanced Transforming Growth Factor β Signaling Rescues Defective Differentiation of Smooth Muscle Cell in Bicuspid Aortic Valve With Thoracic Aortic Aneurysm

Individuals with bicuspid aortic valves (BAV) are at a high risk to develop a thoracic aortic aneurysms (TAA) than patients with trileaflet aortic valves (TAV), most commonly involving ascending aorta and sparing the descending aorta. Smooth muscle cells (SMCs) in the ascending and descending aorta arise from neural crest and paraxial mesoderm, respectively. We hypothesize the aortopathy associated with BAVs is due to aberrant differentiation of neural crest stem cells (NCSCs) to SMCs. Induced pluripotent stem cell (iPSC) lines were established from a patient with BAV/TAA, and control patients with TAV and a normal aorta. The iPSCs pluripotency was verified by standard stem cell markers and teratoma formation in SCID mice. iPSCs were differentiated into NCSCs and paraxial mesoderm cells (PMCs) separately, and verified by specific neural crest markers and paraxial mesoderm markers. Both NCSCs and PMCs were differentiated into SMCs, NCSC-SMCs and PMC-SMCs, by treating with TGFβ1 and PDGF-bb. With differenti...