COMPOSITIONS AND METHODS FOR DETECTING CARDIOTOXICITY
A method of screening a composition for cardiotoxicity comprising contacting the composition with cardiomyocytes that have increased fatty acid oxidation and/or diminished glucose oxidation. The cardiomyocytes are preferably prepared by overexpression of COX7A1. The cardiomyocytes are preferably provided in a micropatterned co-culture to provide a mature functional hPSC-CM cardiotoxicity model.
1 . A method of screening a composition for cardiotoxicity comprising contacting the composition with cardiomyocytes that have increased fatty acid oxidation and/or diminished glucose oxidation.
2 . The method of claim 1 , wherein the cardiomyocytes are prepared by overexpression of COX7A1.
3 . The method of claim 1 , wherein the cardiomyocytes are human pluripotent stem cell-derived cardiomyocytes.
4 . The method of claim 1 , wherein the cardiomyocytes are a derived from a human induced pluripotent stem cell line.
5 . A composition comprising a cardiomyocyte or population of cardiomyocytes that primarily utilize fatty acids as an energy source, wherein the cardiomyocyte or population of cardiomyocytes is prepared by overexpression of COX7A1.
6 . A method of generating a mature cardiomyocyte or population of cardiomyocytes, comprising transfecting a human pluripotent stem cell line with COX7A1, differentiating those cells to produce cardiomyocytes, and maturing the cardiomyocytes via expression of COX7A1.
7 . The method of claim 6 , wherein the mature cardiomyocyte or population of cardiomyocytes have increased fatty acid oxidation and/or diminished glucose oxidation relative to cardiomyocytes differentiated from a human embryonic stem cell line not transfected with COX7A1.
8 . The method of claim 6 , wherein the mature cardiomyocyte or population of cardiomyocytes have an increased expression in one or more of CSQ, PLN, RYR2, SERCA/ATP2A2, MyH7, TNNI3, and ADRA1A and/or a decreased expression of one or more of MYH6 and TNNI1 than cells not expressing COX7A1.
9 . The method of claim 6 , wherein COX7A1 is transfected by a knock-in inducible COX7A1 expression cassette.
10 . The method of claim 6 , wherein COX7A1 is available by constitutive expression.
11 . The method of claim 1 , wherein the screening is conducted in a culture vessel wherein at least one type of cardiomyocyte is on a micropatterned surface that orients the cardiomyocytes in a specific pattern.
12 . The method of claim 11 , wherein the cardiomyocytes on the micropatterned surface are ventricular cardiomyocytes.
13 . The method of claim 11 , wherein ventricular cardiomyocytes on the micropatterned surface have at least one contact point with nodal cells.
14 . The method of claim 11 , wherein the micropatterened surface comprises fibronectin.
15 . The method of claim 11 , wherein the cardiomyocytes are cocultured with at least one secondary cell capable of improving cardiomyocyte maturity.