The duct of von Ebner's glands is a source of taste bud progenitors and susceptible to pathogen infections.

Introduction: We have recently demonstrated that -expressing ( ) cells give rise to mainly type-III neuronal taste bud cells that are responsible for sour and salt taste. The two tissue compartments containing cells in the surrounding of taste buds include the connective tissue core of taste papillae and von Ebner's glands (vEGs) that are connected to the trench of circumvallate and foliate papillae.

Methods: In this study, we performed single cell RNA-sequencing of the epithelium of mouse circumvallate/vEG complex and used inducible Cre mouse models to map the cell lineages of vEGs and/or connective tissue (including stromal and Schwann cells).

Results: Transcriptomic analysis indicated that expression was enriched in the cell clusters of vEG ducts that contained abundant proliferating cells, while expression was enriched in type-III taste bud cells and vEG ductal cells. lineage mapping showed that the traced cells were distributed in circumvallate taste buds concurrently with those in the vEGs, but not in the connective tissue. Moreover, multiple genes encoding pathogen receptors were enriched in the vEG ducts hosting cells.

Discussion: Our data supports that it is the vEGs, not connective tissue core, that serve as the niche of taste bud progenitors. If this is also true in humans, our data indicates that vEG duct is a source of taste bud progenitors and susceptible to pathogen infections.