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Abstract 16350: Regulation of Gene Expression in Human Induced Pluripotent Stem Cell-derived Cardiomyocytes Using Magnetic Nanoparticles


 Background.
 Delivery of transgenes into human induced pluripotent stem cell (hiPSC)-derived cardiomyocytes (hiPSC-CMs) represents an important tool in cardiac regeneration and has potential for clinical applications. Gene transfection into hiPSC and hiPSC-CMs, however, is more difficult than for somatic cells. Despite multiple other methods (i.e. nucleofection, lipofectamine, and viral-based transduction), efficiency, cytotoxicity, safety and cost remain unsatisfactory. Increasingly, nanoparticles (NPs) have been used in biomedical research as a powerful tool in drug delivery and personalized medicine. The objective of this study is to examine the regulation of gene expression in hiPSC and hiPSC-CMs using magnetic NPs.
 
 
 Methods and Results.
 HiPSCs and hiPSC-CMs were transfected using magnetic NPs. Confocal microscopy and flow cytometry confirmed and quantitated the transfection efficiency. Enhanced green fluorescence protein (eGFP) and eGFP-fused membrane proteins served as positive controls. We compared the transfection efficiency of hiPSCs with that of human embryonic kidney cells (HEK 293). We observed that the averaged efficiency in hiPSCs is 43 ± 2 % compared to that of 62 ± 4% in HEK 293. Further analysis of the transfected hiPSCs showed that the pluripotency is not altered by NPs. NPs were also used to direct cardiac differentiation using cardiomyocyte-specific transcription factors. Finally, robust transfection of hiPSC-CMs was obtained using NPs to direct the expression of small-conductance Ca
 2+
 -activated K
 +
 (SK) channels. Patch-clamp recordings demonstrated successful maturation of hiPSC-CMs with respect to the resting membrane potentials and spontaneous action potentials.
 
 
 Conclusion.
 The difficult-to-transfect hiPSCs and hiPSC-CMs were efficiently transfected using magnetic NPs. Our study offers an enhanced approach to direct cardiac differentiation and maturation of hiPSC-CMs without the need for viral vector generation.
 
 Funded by AHA (14BGIA18870087 to XZ), NIH K12 (#UL1 TR000002 to JEL) and Harold Amos Medical Faculty Development Program, RWJ Foundation (to JEL), and California Institute of Regenerative Medicine (CIRM, RB4-05764 to DKL), and Fellowship Awards to PS and JS from CIRM Training Program to UC Davis.