A New Mutant Gene Lowering Amylose Content in Endosperm Starch of Rice, Oryza sativa L.

Abstract

Mesenchymal stem cells (MSCs), which can differentiate into multiplemesodermal tissues, may be useful for autologous cell transplantation,if MSCs, which are isolated from bone marrow in small numbers, canbe expanded in vitro. We developed a combined methodological approachto enrich and proliferate MSCs in vitro using magnetic nanoparticles.Our magnetite cationic liposomes (MCLs), which have a positive surfacecharge in order to improve adsorption, accumulated in MSCs at a concentrationof 20 pg of magnetite per cell. The MCLs exhibited no toxicity againstMSCs in proliferation and differentiation to osteoblasts and adipocytes.The MSCs magnetically labeled by MCLs were enriched using magnetsand then cultured, resulting in much higher density (seeding density,1000 cells/cm2) than in ordinary culture (seeding density, 18 cells/cm2).When MSCs were seeded at high density using MCLs, there was a 5-foldincrease in the number of cells, compared to culture prepared withoutMCLs. Our results suggest that this novel culture method using magneticnanoparticles can be used to efficiently expand MSCs for clinicalapplication.