Understanding the Role of Fluidic Microenvironment in Stem Cell Suspension Culture toward Scalable Biomanufacturing

University Of California-Riverside, Riverside CA

Investigators

Abstract

Human pluripotent stem cells (hPSCs) and cells that differentiate from these are anticipated to be in great demand for cell-based therapies and engineered tissues. In order to meet this demand, these cells need to be made available in sufficient number to supply both laboratories and, in the future, treating physicians. Therefore, they actually need to be manufactured. Three-dimensional (3D) stirred suspension culture, due to its scalability and ease of automation, is a promising platform for meeting such a demand, while potentially reducing the cost of production significantly. However, culturing undifferentiated hPSCs using this technique is a relatively new development in the past several years, and little is known about the role of the fluid environment and stirring process on the cells? expression of various traits. This research will investigate the effect of shear forces applied through the fluid environment on the cells, including their gene expression, differentiation, and survival. The new discoveries and tools anticipated from this study are expected to be applicable to studies of other medically relevant cell types, such as neurospheres, pancreatic islets, and adult stem cells, potentially addressing the existing bottlenecks that reduce the efficiency of their current production. In conjunction with the outlined research activities, the project will develop and integrate several outreach and educational activities, including: developing new crosscutting course materials for stem cell biology and mechanical engineering courses; recruiting and mentoring both undergraduate and graduate students, particularly women and underrepresented minorities, in cutting-edge research; and engaging local K-12 teachers and students through outreach efforts. The current research aims to address a critical knowledge gap relevant to stem cell biomanufacturing, by undertaking three tasks: 1) determining the roles of fluidic shear on growing stem cell aggregates; 2) identifying biomolecular mechanisms of shear-induced mechanotransduction; and 3) designing and verifying a suspension culture that will impose uniform shear on the stem cells. Expected outcomes of this research effort include 1) quantitative correlations between shear stress, aggregate size, and cell fates, 2) molecular pathway models for shear-controlled mechanotransduction, and 3) new means to apply and quantify homogeneous shear stress inputs to the stem cells and their aggregates. Collectively, these outcomes are expected to enable a novel approach to expand and differentiate stem cells using the fluidic microenvironment (e.g., fluid shear) as a critical input parameter.