Fig. 4.

Production of macrophage inflammatory protein 2 (MIP-2) (a), interleukin (IL)-1β (b) and IL-6 (c) in middle ear effusions in wild-type mice and mutant mice. Chemoattractant receptor-homologous molecule expressed on Th2 cells (CRTH2)^–/– mice, D prostanoid receptor (DP)^–/– mice and DP^–/– CRTH2^–/– mice were injected with lipopolysaccharide (1 mg/ml, 20 µl) and cytokine concentrations were determined as shown in Fig. 3 (n = 6–10 per group).