Fig. 1

Investigated culture modalities. a Cells grown in a static suspension culture CellSTACK modality with methylcellulose exhibit the desired sphere phenotype. b Cells grown in waterwheel form into sheets rather than spheres. c Cells grown in Erlenmeyer flasks attach to vessel wall rather than in suspension. d Cells grown in Wave Bioreactor Bag form large rafts rather than spheres. e Cells form spheres when grown at low agitation in STR, however large spheres grow too large in size causing issues with oxygen transport and settling out of solution. f A large portion of cells grown at low agitation in STR attach to vessel surfaces impacting growth dynamics. g Cells grown at high agitation speeds in STR show some sphere growth but predominantly form single cells. h Using a ramped agitation profile with low initial RPM and high final RPM we are able to grow spheres in STR and limit cell attachment