Familial hypertrophic cardiomyopathy (HCM) is the leading cause of sudden cardiac death in young people, including trained athletes, and is the most common inherited heart defect.
In this proposal, we will generate human induced pluripotent stem cell-derived cardiomyocytes (i PSC-CMs) from patients with HCM.
The specific aims are as follow: Specific Aim 1: Generate i PSCs from patients with HCM and healthy controls.
Specific Aim 2: Determine the extent of disease by performing molecular and functional analyses of hi PSC-CMs.
Specific Aim 3: Rescue the molecular and functional phenotypes using zinc finger nuclease (ZFN) technology.
Over the past year, we have now derived i PSCs from a 10-patient family cohort with the MYH7 mutation.
Established i PSC lines from all subjects were differentiated into cardiomyocyte lineages (i PSC-CMs) using standard 3D EB differentiation protocols.
We found hypertrophic i PSC-CMs exhibited features of HCM such as cellular enlargement and multi-nucleation beginning in the sixth week following induction of cardiac differentiation.
Blockade of calcineurin-NFAT interaction in HCM i PSC-CMs by cyclosporin A (Cs A) and FK506 reduced hypertrophy by over 40%.
In the absence of inhibition, NFAT-activated mediators of hypertrophy such as GATA4 and MEF2C were found to be significantly upregulated in HCM i PSC-CMs beginning day 40 post-induction of cardiac differentiation, but not prior to this point.
Taken together, these results indicate that calcineurin-NFAT signaling plays a central role in the development of the HCM phenotype as caused by the Arg663His mutation.
In this proposal, we will generate and characterize human induced pluripotent stem cell-derived cardiomyocytes (i PSC-CMs) from patients with HCM.
Over the past year, we have characterized the pathological phenotypes from i PSCs derived from a 10-patient family cohort with the MYH7 mutation.
We've differentiated all stablished i PSC lines from all subjects into cardiomyocyte using a modified protocol from that published by Palacek in PNAS 2011.