Binary Colloidal Crystals Drive Spheroid Formation and Accelerate Maturation of Human-Induced Pluripotent Stem Cell-Derived Cardiomyocytes

Abstract

The development of human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) provides significant advances to cell therapy, disease modeling, and drug screening applications. However, the current differentiation protocol is inefficient in mimicking biophysical and biochemical characteristics of cardiac niche. Hence, immature cardiomyocytes are often generated. In this study, hiPSC-CMs were generated on a new family of substrates called monolayer binary colloidal crystals (BCCs). Four BCCs were fabricated with different sizes (2 or 5 or 0.4 or 0.2 μm) and materials [Si or polystyrene (PS) or poly(methyl methacrylate)] abbreviated as 2PS, 5PS, 2PM, and 5PM. BCCs have complex surface micro-/ nanotopographies and heterogeneous chemistries which are important modulators in microenvironments in vitro. The results showed that hiPSCs formed adhered spheroids with strong pluripotent markers (Oct4, Nanog, and Sox2) on PM surfaces compared to PS and flat surfaces. After 30-day differentiation, hiPSC-CMs on PM surfaces showed markedly improved myofibril ultrastructures, Ca 2+ handling, and electrophysiological properties, indicating that more mature hiPSC-CMs were generated. hiPSC-CMs generated on 5PM are more similar to adult heart tissue compared to other surfaces in terms of genes (ACTC1, TNNT2, RYR2, SERCA2a, SCN5a, KCNJ2, CACNA1c, ITGB1, GJA1, MYH6, and MYH7) and protein (ssTnI and cTnI) expressions. We further demonstrated that 5PM surfaces facilitated cadherin switching (from E-to N-) during cardiac differentiation and mature N-cadherin expression, which were positively correlated with the cardiogensis markers (GATA4, MEF2c, and NKX2.5). This study illuminated that a tailored surface nanotopography was beneficial in hiPSC culture and in situ cardiac differentiation. This one-step approach and BCCs can be a next-generation tool for hiPSC expansion and CM differentiation.

Transplantation of human induced pluripotent stem cell-derived cardiomyocytes improves myocardial function and reverses ventricular remodeling in infarcted rat hearts

“…A well-established method of cardiomyocyte differentiation from PSCs provides an ideal source of cardiomyocytes and makes regenerative therapy for myocardial muscle damage a promising strategy. The methods of cardiomyocyte differentiation, purification, and maturation from iPSCs or ESCs have been established both by our lab [9][10][11][12] and other labs [13][14][15][16][17]. Recently, transplantation of human ESC-derived cardiomyocytes (ESC-CMs) has been proven to significantly improve cardiac function in infarcted rat and nonhuman primate hearts [18,19] due to the capacity of PSC-CMs to remuscularize the infarcted hearts and form electromechanical junctions with the host hearts [15].…”

Maturation strategies and limitations of induced pluripotent stem cell-derived cardiomyocytes

“…Only the cells in the 9 kPa hydrogel showed organized sarcomere structure and significantly increased contractility [120]. Perhaps a potential mechanism for 5PM to induce maturation [122]. However, the organized arrangement of CMs is the key to maintaining the mechanical properties of the heart.…”

Colloidal Photonic Crystals for Biomedical Applications

“…[ 77 ] Colloidal PCs have recently attracted notable research interest owing to their adjustable periodic micro/nanostructures and diversity of material choices. [ 78 ] Among these colloidal PCs, inverse opals possessing porous structures, which feature the capacity to promote the nutrition/drug infiltration as well as the cell‐substrate interactions, have been widely studied. [ 79 ] For example, we developed stretched inverse opal substrates and studied their ability in establishing the desired cell orientations ( Figure ).…”