1 1 Cytograft Tissue Engineering, Inc., 3 Hamilton Landing, Suite 220, Novato, CA 94949, USA ; 2 Inserm, U1148, Cardiovascular Bio-Engineering, X. Bichat Hospital, 75018 Paris, France ; 3 Université Paris 13, Sorbonne Paris Cité, F-93430 Villetaneuse, France.