Olfactory epithelium (OE)

The **olfactory epithelium** is a specialized region of epithelial tissue located within the nasal cavity that is responsible for detecting odors. It contains several distinct cell types, including **olfactory sensory neurons** (which express odorant receptors on their cilia), **supporting/sustentacular cells** (which provide metabolic support and local immune defense), **basal progenitor cells** (responsible for regeneration), and microvillar/brush cells. The axons from these sensory neurons form the first cranial nerve and project into the brain's olfactory bulb. The OE is unique among neural tissues in its capacity for ongoing neurogenesis throughout life, allowing recovery from certain injuries. However, it is also highly susceptible to damage from infections, chronic inflammation such as rhinosinusitis, environmental toxins, trauma, aging processes, and neurodegenerative diseases—all leading causes of impaired sense of smell. While individual components like *olfactory receptors* are considered therapeutic targets in research contexts, the "olfactory epithelium" itself refers anatomically to an entire tissue rather than a discrete molecular target suitable for direct pharmacological intervention[1][2][4][6]. It is not a single molecular target; rather, it is composed of multiple cell types including olfactory sensory neurons, supporting cells, basal cells, and brush/microvillar cells[1][6]. No drugs directly target the olfactory epithelium as a whole; some drugs may affect its function indirectly via inflammation or infection. The mechanism of action is not applicable to the tissue as a whole. Drugs affecting inflammation or viral replication may impact OE function indirectly. No specific molecular biomarkers for drug targeting are established for the entire OE. Therapeutic interventions would need to consider potential damage/regeneration balance.

Other names

Olfactory mucosaNasal olfactory epithelium