Significance of spiral ligament fibrocytes with cochlear inflammation.

It has been recently suggested that the spiral ligament fibrocytes, which interconnect with the basal cells of the stria vascularis via gap junctions, may be critical in maintaining cochlear homeostasis. In animal models of pathological conditions such as labyrinthitis and otitis media, reduced immunostaining for gap junction protein connexin 26 is observed in the spiral ligament. This suggests that disruption of the spiral ligament fibrocytes could be among the causes of cochlear dysfunction due to cochlear inflammation. Cultured spiral ligament fibrocytes have been shown to secrete chemokines and other mediators after stimulation of proinflammatory cytokine TNF-alpha or IL-1beta. Each of these mediators might induce inflammatory cell movement, which would prolong the inflammatory response. It is reasonable that such enhanced biological defense ability could be the cause of spiral ligament fibrocyte damage.