Fig 8.

Stimulus-specific role of β-arrestin-2 in regulating cytokine production from neutrophils. Neutrophils were obtained from thioglycolate-injected wild-type (WT), β-arrestin-2 homozygous knockout (β-arr2^−/−), and β-arrestin-2 heterozygous (β-arr2^+/−) mice as described in Materials and Methods. Cells were plated (as described in Materials and Methods) and stimulated with LPS and polymicrobial culture at different concentrations and multiplicities of infection (MOI), respectively, for 18 h, and supernatants were assayed for IL-6, IL-10, and TNF-α concentrations. Cytokine levels were transformed as fold over WT basal. *, P < 0.05; **, P < 0.01; ***, P < 0.001; compared to the WT as determined by a 2-way ANOVA followed by a Bonferroni posttest. n = 3 for each genotype.