Induced pluripotent stem cell–derived salivary glands

Abstract Salivary glands are exocrine glands composed of several cell types including ductal, acinar, and basal/myoepithelial cells. Salivary glands, through the production of saliva, play essential roles in the maintenance of proper oral health such as the digestion of starch, swallowing, and the maintenance of teeth. Pluripotent stem cell–derived organoids are three-dimensional self-organizing structures that have recently emerged as a novel model system for investigating embryonic development and disease progression. Organoids serve as a valuable tool in developmental and physiological research, disease modeling, drug screening, and potential cell-based therapies. Organoids can be grown in vitro from pluripotent stem cells by the stepwise manipulation of molecular signals that mimic the signaling cues present during in vivo organ development. Recently, we reported the generation of salivary gland organoids using mouse embryonic stem cells. The salivary gland organoid showed a similar morphology and gene expression profile to the embryonic salivary gland. Moreover, orthotopically engrafted salivary gland organoids exhibited characteristics of mature salivary glands, including saliva secretion. The culture methods used, as well as transplant model, are therefore expected to be a promising model for the understanding of salivary gland development and diseases.