Inner ear progenitor cell (IEPC)

Inner ear progenitor cells (IEPCs) are specialized stem-like cells located within the organ of Corti in the cochlea, often identified by the expression of the marker Lgr5. These cells serve as the biological source for auditory hair cells during development, but they become largely quiescent in the adult mammalian ear, leading to permanent sensorineural hearing loss when hair cells are damaged (McLean et al., 2017). Therapeutic strategies focus on pharmacologically re-activating these progenitors to induce the formation of new, functional hair cells through the modulation of developmental pathways such as Wnt and Notch (Edge & Albert, 2019). For example, the drug candidate FX-322 uses a combination of a GSK3 inhibitor and an HDAC inhibitor to promote the expansion and differentiation of these Lgr5-positive cells (Ren et al., 2019). By targeting the regenerative potential of IEPCs, researchers aim to restore hearing sensitivity by repairing the cellular architecture of the inner ear rather than relying on external amplification devices. This approach represents a significant frontier in regenerative medicine for treating hearing impairment and related auditory disorders.

Other names

Cochlear hair cell progenitorOtic progenitor cellLgr5-positive supporting cellAuditory progenitor cellCochlear progenitor cell

Activation of Wnt signaling pathways and inhibition of Notch signaling to induce the proliferation and trans-differentiation of endogenous supporting cells into functional auditory hair cells.