Short-Term Regulation of FcγR-Mediated Phagocytosis by TLRs in Macrophages: Participation of 5-Lipoxygenase Products

Figure 3

The ability of TLR agonists to enhance FcγR-mediated phagocytosis is modulated by 5-LO pathway. (a) Rat AMs and (b) mice BMDM were pretreated with medium containing 5-LO inhibitor (zileuton 20 μM) and FLAP inhibitor (MK886, 1 μM) for 20 min. After this period, TLR agonists were added in cell culture, followed by RBCs or IgG-RBCs (1 : 40) in addition. (c) BMDM from WT and 5-LO^−/− mice were also pretreated TLR agonists and challenged with RBCs or IgG-RBCs (1 : 40). All experiments used TLR2 (Pam3Cys: 25 μg·ml⁻¹), TLR3 (poly I:C: 1 μg·ml⁻¹), or TLR4 (LPS: 1 μg·ml⁻¹) agonists for 1 h. Results are expressed as the mean ± SEM. Values are presented as the percentage of the IgG-RBC group and the negative control group, and the RBC control group was discounted from all groups. compared to the IgG-RBC group; ^# compared to the IgG-RBC group treated with zileuton + MK886 (a, b) or IgG-RBC 5-LO^−/− (c); or compared to respective the TLR group (without treatment or SV129), determined by Student’s t-test. The experiment is a representative of three independent experiments performed in heptaplicate.

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