A Small Molecule that Promotes Cardiac Differentiation of Human Pluripotent Stem Cells under Defined, Cytokine- and Xeno-free Conditions

Abstract

Human pluripotent stem cells (hPSCs), including embryonic stem cells and induced pluripotent stem cells, are potentially useful in regenerative therapies for heart disease. For medical applications, clinical-grade cardiac cells must be produced from hPSCs in a defined, cost-effective manner. Cell-based screening led to the discovery of KY02111, a small molecule that promotes differentiation of hPSCs to cardiomyocytes. Although the direct target of KY02111 remains unknown, results of the present study suggest that KY02111 promotes differentiation by inhibiting WNT signaling in hPSCs but in a manner that is distinct from that of previously studied WNT inhibitors. Combined use of KY02111 and WNT signaling modulators produced robust cardiac differentiation of hPSCs in a xeno-free, defined medium, devoid of serum and any kind of recombinant cytokines and hormones, such as BMP4, Activin A, or insulin. The methodology has potential as a means for the practical production of human cardiomyocytes for regeneration therapies.

Chemical approaches to studying stem cell biology

“…They found a small molecule (KY02111) that when applied on days 4-8 of induction could increase GFP expression, whereas treatment on days 0-4 completely repressed GFP expression. Preliminary data suggested that KY02111 suppressed Wnt signaling downstream GSK3β in the canonical Wnt signaling pathway, but its precise target remains unknown [31]. Similarly, another study showed that treatment for 48 h by high concentrations of the GSK3 inhibitor CHIR99021 can induce highly efficient primitive streak induction from hESCs.…”

Constraining the Pluripotent Fate of Human Embryonic Stem Cells for Tissue Engineering and Cell Therapy – The Turning Point of Cell-Based Regenerative Medicine

“…As an alternative approach to iPS cells, known neural-fate determining genes or chemicals were recently used to transdifferentiate or reprogram fibroblasts or tissues into induced adult neural cells by genetic engineering or induction with extremely low efficiencies [55–59]. Similarly, known cardiac-fate determining genes or chemicals were recently used to transdifferentiate or reprogram fibroblasts or tissues into induced adult cardiac progenitors and cardiomyocytes by genetic engineering or induction with extremely low efficiencies [60–63]. Reprogrammed somatic cells have historically been associated with abnormal gene expression, accelerated senescence, and immune-rejection following transplantation [21,51–54].…”

“…These major drawbacks have severely impaired the utility of reprogrammed or deprogrammed or direct/trans-differentiated somatic cells as viable therapeutic approaches. Although small molecules used to induce hESC lineage-specific therapy derivatives are usually safe developmental signal molecules and morphogens, it should be cautious of the small molecules used in the reverse process to generate iPS cells or trans-differentiation, which are known toxic cancerogenic chemicals with too dangerous or even lethal side effects to be used for patients [3,21,48,49,63]. …”

Future Treatment of Heart Failure Using Human iPSC-Derived Cardiomyocytes

“…However, to obtain hundreds of millions of cardiomyocytes, it is necessary to establish a cardiac differentiation method that is both efficient and cost-effective due to the many expensive recombinant protein factors used. To address this problem, Minami et al [11] screened small-molecule compounds to identify those that significantly increase cardiac differentiation induction, and they revealed some inhibitors of canonical Wnt signaling as candidates. In addition, Several studies then showed that induction techniques in ESCs could also be applied to iPSCs, although differentiation efficiencies were suggested to be inferior compared to ESCs.…”