Fig. 2

TLR4⁺ cells in the rat cochlea 7 days post-intratympanic injection of 0.4 % AgNPs shown by immunofluorescence confocal microscopy or immunohistochemistry. In the cochleae exposed to dH₂O, the strial basal cells (SBCs) and spiral ligament fibrocytes (SLFs) showed mild staining (d), while the spiral ganglion cells (SGCs), hair cells (HCs), pillar cells (PCs), and Deiters’ cells (DCs) of Corti’s organ (CO) demonstrated extremely weak staining (f, h). In the cochleae exposed to 0.4 % AgNPs, the SBCs and SLFs exhibited more intensive staining that was independent of the cochlear turn (a–c). In CO, the inner hair cells (IHCs), PCs, and DCs displayed more intensive staining, but the outer hair cells (OHCs) did not (g). However, the SGCs did not show any changes (e). Comparisons of staining intensity are shown in i and j. Scale bar = 30 μm