Abby Bernard showed that pancreatic beta-cells aggregates could be formed in photopolymerized microwell devices. These cell aggregates secreted significantly more insulin per cell than dispersed cells.
A.B. Bernard, C.C. Lin, and K.S. Anseth, "A Microwell Culture Platform for the Aggregation of Pancreatic Beta-Cells," Tissue Engineering Part C-Methods, 18 (8), 583-592 (2012).