D Hay - Centre for Regenerative Medicine, Ins titute for Regeneration andRepair, The University of Edinburgh, Edinburgh, UK

Liver disease represents an increasing cause of global morbidityand mortality. Currently, liver transplant is the only treatmentcurative for end s tage liver disease. Donor organs cannot meetthe demand and therefore, scalable treatments and new diseasemodels are required to improve clinical intervention.Pluripotent s tem cells represent a renewable source of humantissue. Recent advances in three-dimensional cell culture hasprovided the field with more complex sys tems that better mimicliver physiology and function. Despite these improvements,current cell-based models are highly variable in performanceand expensive to manufacture at scale. This is due, in part, tothe use of poorly defined or cross-species materials within theprocess, severely affecting technology translation. To addressthis issue, we have developed an automated and economicalplatform to produce liver tissue at scale for modelling diseaseand small molecule screening. S tem cell derived liver spheres were formed by combining hepatic progenitors with endothelialcells and s tellate cells, in the ratios found within the liver. Theresulting tissue permitted the s tudy of human liver biology ‘inthe dish ‘and could be scaled to levels that may prove useful tosupporting failing liver function in humans.