Methods and compositions for preparing cardiomyocytes from stem cells and use thereof

Abstract

The present invention discloses novel compositions and methods for enhancing cardiac differentiation efficiency of stem cells or promoting ventricular and atrial cardiomyocytes formation from stem cells. The present invention also discloses the atrial and ventricular cardiomyocytes formed from the stem cells, and the uses of the cardiomyocytes for repairing cardiac injuries and screening for new medicaments for treating cardiac injuries.

1 - 77 . (canceled) 
     
     
         78 . A pharmaceutical composition for treating a cardiac injury or disorder, which pharmaceutical composition comprises an effective amount of a ventricular cardiomyocyte differentiated, in vitro, from a mesodermal cell in which the retinoic acid signaling pathway is inhibited by an exogenous agent to promote ventricular cardiomyocyte formation from the mesodermal cell. 
     
     
         79 . The pharmaceutical composition of  claim 78 , wherein the mesodermal cell is differentiated from a pluripotent stem cell, a totipotent stem cell, a multipotent stem cell, an oligopotent stem cell, a unipotent stem cell, an embryonic stem cell, an induced pluripotent stem cell, a fetal stem cell, or an adult stem cell. 
     
     
         80 . The pharmaceutical composition of  claim 78 , wherein the mesodermal cell is differentiated from a mammalian stem cell. 
     
     
         81 . The pharmaceutical composition of  claim 78 , wherein the mesodermal cell is differentiated from a human stem cell, a human embryonic stem cell, or a human induced pluripotent stem cell. 
     
     
         82 . The pharmaceutical composition of  claim 78 , wherein the mesodermal cell is generated by contacting a stem cell with basic fibroblast growth factor (bFGF), BMP 4 and/or activin A. 
     
     
         83 . The pharmaceutical composition of  claim 78 , wherein the mesodermal cell is generated by contacting a stem cell with Wnt-3a, Bio, or CHIR99021. 
     
     
         84 . The pharmaceutical composition of  claim 78 , wherein the mesodermal cell is is treated with a BMP antagonist. 
     
     
         85 . The pharmaceutical composition of  claim 84 , wherein the BMP antagonist is selected from the group consisting of a BMP 4 antagonist, Noggin, Chordin, Tsg, a BMP soluble receptor, BMPRIA, BMPRIB, and Dorsomorphin. 
     
     
         86 . The pharmaceutical composition of  claim 78 , wherein the mesodermal cell is treated with a Wnt inhibitor or dickkopf homolog 1 (DKK1). 
     
     
         87 . The pharmaceutical composition of  claim 78 , wherein the exogenous agent is selected from the group consisting of a pan-retinoic acid receptor antagonist, a retinoic acid antagonist, a retinoic acid receptor antagonist, and a retinoic X receptor antagonist. 
     
     
         88 . The pharmaceutical composition of  claim 78 , wherein the retinoic acid signaling pathway of the mesodermal cell is inhibited by contacting the mesodermal cell with the exogenous agent that reduces vitamin A, or by contacting the mesodermal cell with the exogenous agent that does not comprise vitamin A. 
     
     
         89 . The pharmaceutical composition of  claim 78 , which comprises cardiomyocytes comprising a population of ventricular cardiomyocytes differentiated, in vitro, from mesodermal cells in which the retinoic acid signaling pathway is inhibited by an exogenous agent to promote ventricular cardiomyocytes formation from the mesodermal cells. 
     
     
         90 . The pharmaceutical composition of  claim 89 , wherein at least 90%, at least 95%, at least 99%, or 100% of the cardiomyocytes are ventricular cardiomyocytes. 
     
     
         91 . The pharmaceutical composition of  claim 78 , which further comprises a pharmaceutically acceptable carrier or excipient.