Project description:The lineage of the horizontal basal cells (HBC) stem cells and their descendants from the olfactory epithelium were profiled by single-cell RNA-Seq to identify differentiated cell types, intermediate stages, transition states, and to infer the lineage trajectories.
Project description:The lineage of wild-type horizontal basal cells (HBC) stem cells from the olfactory epithelium were profiled by single-cell RNA-Seq (10X v2 chemistry) to identify differentiated cells types, intermediate stages, transition states, and to infer the lineage trajectories.
Project description:The lineage of the horizontal basal cells (HBC) stem cells and other Sox2eGFP-positive cells from the olfactory epithelium were profiled by single-cell RNA-Seq to identify differentiated cells types, intermediate stages, transition states, and to infer the lineage trajectories.
Project description:The lineage of wild-type horizontal basal cells (HBC) stem cells from the olfactory epithelium were profiled by single-cell RNA-Seq (10X v3 chemistry) to identify differences in aged versus not-aged adult stem cells mRNA expression profiles
Project description:Unlike most of the adult nervous system, the olfactory epithelium (OE) can regenerate neurons lost during normal homeostasis or after injury. This life-long regeneration is propagated by two populations of stem cells, the actively proliferating globose basal cells (GBCs) and the dormant horizontal basal cells (HBCs). HBCs only activate and contribute to epithelial regeneration in the context of severe injury, and this activation is mediated by the loss of the transcription factor Tp63. While the HBC differentiation trajectories that occur after activation have been described with lineage tracing and single-cell RNA seq experiments, the immediate consequences of injury on HBC gene expression and fate commitment have not been explored. We present an in vitro model of the acute activation process for HBCs in response to treatment with phorbol 12-myristate 13-acetate (PMA) to explore the molecular underpinnings of these early activation events. We find that treating HBCs with PMA induces the rapid degradation of TP63, and we find that this effect is partially reversed when cells are allowed to recover in maintenance media. Using bulk RNA sequencing we found that PMA-treated HBCs pass through various stages of acute activation identifiable by specific gene regulatory signatures. These transcriptomic phases are associated with varying degrees of plasticity with regards to activated HBCs ability to engraft in transplant models.
Project description:The olfactory neuroepithelium serves as a sensory organ for odors and forms part of the nasal mucosal barrier. Olfactory sensory neurons are surrounded and supported by epithelial cells. Among them, microvillous cells (MVCs) are strategically positioned at the apical surface, but their specific functions are enigmatic and their relationship to the other specialized epithelial cells, particularly the solitary chemosensory cell family, is unclear. Here, we establish that the family of MVCs comprises tuft cells and ionocytes in both mice and humans. Integrating analysis of the respiratory and olfactory epithelia, we define the unique receptor expression of TRPM5+ tuft-MVCs compared to Gɑ-gustducinhigh respiratory tuft cells and characterize a new population of glandular DCLK1+ tuft cells. To establish how allergen sensing by tuft-MVCs might direct olfactory mucosal responses, we employed an integrated single-cell transcriptional and protein analysis. Inhalation of Alternaria induced mucosal epithelial effector molecules including Chil4, and a distinct pathway leading to proliferation of the quiescent olfactory horizontal basal stem cell (HBC) pool, both triggered in the absence of olfactory apoptosis. While the Chil4 pathway was dependent on STAT6 signaling and innate lymphocytes, neither were required for HBC proliferation. Alternaria- and ATP- elicited HBC proliferation was dependent on tuft-MVCs, establishing these specialized epithelial cells as regulators of olfactory stem cell responses. Together our data provide high resolution characterization of nasal tuft cell heterogeneity and uncover a novel function for TRPM5+ tuft-MVCs in directing the olfactory mucosal response to allergens.
Project description:We report bulk RNAseq of in vitro cultured horizontal basal cells, and in vivo isoalted respiratory basal cells of the murine olfactory epithelium, and compared their profiles with pre-existing bulk RNAseq of in vivo isolated HBCs and single cell RNAseq of in vivo HBCs.
Project description:Although the olfactory mucosa possesses long-lived horizontal basal stem cells (HBCs) and remarkable regenerative capacity, the function of human olfactory neuroepithelium is significantly impaired in the setting of chronic rhinosinusitis. Here we used RNA sequencing to analyze the transcriptional profile of mouse HBCs in a chronic inflammatory milieu. Global gene expression analysis in inflamed HBCs reveals broad upregulation of NF-κB-regulated cytokines and chemokines accompanied by enhancement of “stemness”-related transcription factors. Our results provide evidence of basal stem cells as direct participants in the progression of chronic inflammation and identify a concomitant functional switch away from neuroregeneration.
Project description:The Vomeronasal organ (VNO) is a part of the accessory olfactory system, which is responsible for detecting pheromones, chemical factors that trigger a spectrum of sexual and social behaviors. The vomeronasal epithelium (VNE) shares several features with the epithelium of the main olfactory epithelium (MOE). However, it is a distinct neuroepithelium populated by chemosensory neurons that differ from the olfactory sensory neurons (OSNs) in cellular structure, receptor expression, and connectivity. The vomeronasal organ of rodents comprises a sensory epithelium and a thin nonsensory epithelium that morphologically resembles the respiratory epithelium. Sox2-positive cells have been previously identified as the stem cell population that gives rise to neuronal progenitors in MOE and VNE. In addition to these, the MOE also comprises p63 positive horizontal basal cells (HBCs), a second pool of quiescent stem cells that become active in response to injury. Immunolabeling against the transcription factor p63, Keratin-5 (Krt5), Krt14 and Krt5Cre tracing experiments highlighted the existence of horizontal basal cells distributed along the basal lamina of the VNO forming from progenitors along the basal lamina oft the marginal zones. Moreover, these experiments revealed that the NSE of rodents is, like the respiratory epithelium, a stratified epithelium where the p63/Krt5+ basal cells self-replicate and give rise to the apical columnar cells facing the lumen of the VNO.