Figure 5.

IL-4 inhibits TDB-induced cytokine production in murine macrophages. Bone marrow-derived macrophages were stimulated for 24 h with TDB or LPS in the presence or absence of IL-4. Cytokine levels in cell culture supernatant were quantified using ELISA [(A), G-CSF, and (B), TNF]. (A,B) Depicted are mean ELISA values of replicates from six independent experiments. Supernatants of BMM treated with media or IL-4 alone did not contain significant amounts of G-CSF or TNF (data not shown). Statistical significance of the effect of IL-4 on stimulation with TDB and LPS, respectively, was tested using a two-sided paired t-test. *p < 0.05, ***p < 0.001.