Abstract
Human pluripotent stem cells are a potentially powerful cellular resource for application in regenerative medicine. Because such applications require large numbers of human pluripotent stem cell-derived cells, a scalable culture system of human pluripotent stem cell needs to be developed. Several suspension culture systems for human pluripotent stem cell expansion exist; however, it is difficult to control the thickness of cell aggregations in these systems, leading to increased cell death likely caused by limited diffusion of gases and nutrients into the aggregations. Here, we describe a scalable culture system using the cell fiber technology for the expansion of human induced pluripotent stem (iPS) cells. The cells were encapsulated and cultured within the core region of core-shell hydrogel microfibers, resulting in the formation of rod-shaped or fiber-shaped cell aggregations with sustained thickness and high viability. By encapsulating the cells with type I collagen, we demonstrated a long-term culture of the cells by serial passaging at a high expansion rate (14-fold in four days) while retaining its pluripotency. Therefore, our culture system could be used for large-scale expansion of human pluripotent stem cells for use in regenerative medicine.
Highlights
Human pluripotent stem cells, including embryonic stem (ES) cells[1] and induced pluripotent stem cells[2], are capable of expanding indefinitely and differentiating into cells from all three germ layers
To demonstrate the function of the core-shell microfiber culture system that can restrict the increase in the thickness of cell aggregation and can subsequently maintain cell viability, we compared this system with the conventional suspension culture system
We found that the expansion rate of human induced pluripotent stem (iPS) cells accompanied with type I collagen at low initial cell density was higher than the other types of microfibers, and the value of the rate was 13 ± 1.3-fold in 4 days (Fig. 4A)
Summary
Human pluripotent stem cells, including embryonic stem (ES) cells[1] and induced pluripotent stem (iPS) cells[2], are capable of expanding indefinitely and differentiating into cells from all three germ layers. In cell transplantation, approximately 109 cardiomyocytes are required for treating myocardial infarction, approximately 109 insulin-producing β cells for type 1 diabetes mellitus, and approximately 1010 hepatocytes for hepatic failure[4] To obtain these large numbers of cells, the development of scalable culture systems with efficient expansion of human pluripotent stem cells is needed before subsequent differentiation steps[6]. We developed a method to restrict the increase in the thickness of human iPS cell aggregations during cell expansion using the cell fiber technology This technology enables encapsulation of the cells suspended in the culture medium or extracellular matrix (ECM) solution into the core-shell hydrogel microfibers[16, 17] (Fig. 1A). We demonstrated long-term cell proliferation by serial passaging while sustaining a high expansion rate and pluripotency using our culture system
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
