Morpho-elasticity of human pluripotent stem cell cysts

Human induced pluripotent stem cells (hiPSCs) are a promising cellular source in cell therapies or regenerative medicine and they allow to address fundamental mechanisms in embryo genesis. However, their culture to provide large amounts of high quality stem cells remains challenging. Here, using an encapsulation microfluidic device, we observe that hiPSCs self organize into cysts, which are spherical closed epithelia reminiscent of the early stages of in vitro embryo models. We monitor their morphology, organization and growth in a pseudo stratified epithelium before and after they get confined by the capsule wall. Then, we present a morpho-elastic model to quantitatively explain the growth dynamics. The model based on NeoHookean elasticity with anisotropic growth shows that the stresses, concentrated within the cyst, remain at a low level. Cyst growth is shown to be quasi-exponential, slightly reduced by a compression-induced correction. We hypothesize that this peculiar morphological dynamics, which is controlled by elasticity and anisotropic growth, might provide new strategies to optimize the production of medical grade hiPSCs.

Automated summary

The study shows that human induced pluripotent stem cells can self-organize into cyst-like structures using an encapsulation microfluidic device. This finding may offer new strategies for optimizing the production of medical grade hiPSCs.