Particle-tracking-based strategy for the optimization of agitation conditions in a suspension culture of human induced pluripotent stem cells in a shaking vessel

Abstract

Suspension cultures are widely used for cell expansion in regenerative medicine and production. Shaking culture is one of the useful suspension culture methods that ensures gentle agitation. There are other shaking methods, including orbital shaking, reciprocating, and rocking; however, optimizing the shaking conditions for each method to meet cell culture requirements is time-consuming. In this study, we used a particle-tracking-based strategy for optimizing the agitation conditions. When the average accelerations of aggregates were calculated, high acceleration occurred periodically, and acceleration of the aggregates in orbital shaking was stable. Furthermore, the number of dead cells correlated with the average time of acceleration. We observed that cell growth was ideally maintained by factors such as optimal acceleration, aggregate formation, and cell death. These results indicate that the image-based analyses of aggregates help optimize the agitation conditions for the shaking suspension culture of induced pluripotent stem cells (iPSCs).