Table 1.

Summary of established methods for human pseudoislet formation

Method	Approach	Advantages	Disadvantages	Key references
Spontaneous reaggregation	After dissociation, islet cells are introduced to ultra-low attachment plates and reaggregate spontaneously into pseudoislets	Accessible and widely validated in transduction experiments	Produces pseudoislets of heterogeneous size (although greater homogeneity can be achieved by reducing the volume of culture media and using gentle centrifugation)	Liu et al. (2019), Zaldumbide et al. (2013), Arda et al. (2016), Peiris et al. (2018), Bevacqua et al. (2021a & 2021b)
Microwell	After dissociation, islet cells are concentrated into small-diameter wells in customized microwell plates to achieve size-controlled clusters	Achieves pseudoislets of uniform size and efficient for large-scale experiments	Limited by cost of microwell plates	Liu et al. (2019), Hilderink et al. (2015), Yu et al. (2018)
Hanging drop	After dissociation, islet cells are suspended in small liquid droplets (for example, distributed across inverted tissue-culture dish lids), and gravity facilitates the formation of spherical clusters	Accessible and achieves pseudoislets of uniform size	Laborious (although modified hanging-drop platforms that are compatible with automated cell seeding have facilitated larger-scale studies)	Zuellig et al. (2017), van Krieken et al. (2019), Walker et al. (2020)