Clinically compliant enrichment of human pluripotent stem cell–derived islets

Human pluripotent stem cell–derived islet (SC-islet) transplantation is a promising β cell replacement therapy for patients with type 1 diabetes, offering a potential unlimited cell supply. Yet, the heterogeneity of the final cell product containing non–target cell types has relevant implications for SC-islet function, transplant volume, and cell product safety. Here, we present a clinically compliant, full three-dimensional differentiation protocol that includes a purification step of endocrine cell–rich clusters, relying on the principle of isopycnic centrifugation (density gradient separation). Enriched SC-islets displayed signs of functionality in vitro and in vivo. In contrast with antibody-based single-cell sorting approaches, this method does not destroy the islet cytoarchitecture associated with alterations of islet function and cell loss. Furthermore, it is fast, is easily scalable to large cell volumes, and can be applied during cell manufacturing. This method may also contribute to the generation of improved cell-based therapies for regenerative medicine purposes beyond the SC-islet field.