Immunolocalization of prestin in the human cochlea

Objective: Prestin is an anion-transporter-related protein highly expressed in mammalian outer hair cells (OHCs). It is associated with the OHC basolateral plasma membrane and responsible for cell body contraction, increasing cochlear sensitivity and frequency resolution. Here, we analysed the expression and distribution of prestin in the human cochlea. Study Design: Immunohistochemistry including confocal microscopy and SEM were performed on EDTA-decalcified human cochlea removed during petro-clival meningioma surgery. Results: Prestin was found to be expressed solely in OHCs. No staining was seen in IHCs. Prestin immunolabelling framed the OHCs along the sensory region of the human cochlea. Staining was most prominent in the lateral cell membrane with less expression in the sub- and peri-nuclear part of the cell. Prestin immunostaining was also detected in the OHC cytosol, presumably reflecting intracellular molecular trafficking. Conclusion: This study describes for the first time the localization and distribution of prestin in the well preserved human organ of Corti.