Functional Activity of Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes on a Mouse Renal Subcapsular Xenograft Model

Abstract

For the replacement of lost contractile elements in the treatment of coronary heart disease, the most promising approaches to obtain cardiomyocytes by cardiac differentiation of pluripotent cells. The aim of this work is to develop a technology for the formation of a functional layer of cardiomyocytes differentiated from iPSCs, capable of generating rhythmic activity and synchronous contractions. To accelerate cardiomyocyte maturation, the renal subcapsular transplantation model was used in SCID mice. After explantation, the formation of cardiomyocyte contractile apparatus was assessed by fluorescence and electron microscopy, and calcium ion oscillation in the cytoplasm was assessed by visualization of the fluorescent calcium binding dye Fluo-8. It was shown that human iPSC-derived cardiomyocyte cell layers transplanted (for up to 6 weeks) under SCID mouse kidney fibrous capsules begin to form an ordered contractile apparatus and retain functional activity and the ability to oscillate calcium ion fluxes after explantation from the body.