SLF-derived MCP-1/CCL2 is associated with inner ear inflammation secondary to NTHI-induced OM
in vivo. Murine temporal bones were harvested at 7 days after transtympanic inoculation of saline (A) and live NTHI (B). Immunolabeling shows MCP-1/CCL2 is highly expressed in the spiral ligaments (white arrows) and spiral limbus as well as the serous substances (black arrow) of the NTHI-inoculated mice. In contrast, it is noted that the cochlea of the saline-inoculated group weakly expresses MCP-1/CCL2 except the stria vascularis (arrowheads). Original magnification: ×50.