iPS cell sheets created by a novel magnetite tissue engineering method for reparative angiogenesis

Angiogenic cell therapy represents a novel strategy for ischemic diseases, but some patients show poor responses. We investigated the therapeutic potential of an induced pluripotent stem (iPS) cell sheet created by a novel magnetite tissue engineering technology (Mag-TE) for reparative angiogenesis. Mouse iPS cell-derived Flk-1(+) cells were incubated with magnetic nanoparticle-containing liposomes (MCLs). MCL-labeled Flk-1(+) cells were mixed with diluted extracellular matrix (ECM) precursor and a magnet was placed on the reverse side. Magnetized Flk-1(+) cells formed multi-layered cell sheets according to magnetic force. Implantation of the Flk-1(+) cell sheet accelerated revascularization of ischemic hindlimbs relative to the contralateral limbs in nude mice as measured by laser Doppler blood flow and capillary density analyses. The Flk-1(+) cell sheet also increased the expressions of VEGF and bFGF in ischemic tissue. iPS cell-derived Flk-1(+) cell sheets created by this novel Mag-TE method represent a promising new modality for therapeutic angiogenesis.