Fig. 4

TLR2-dependent signaling is critical for eliciting inflammatory mediator release during MDSC co-culture with microglia or macrophages. Primary microglia or bone marrow-derived macrophages were cultured alone or with bone marrow-derived MDSCs in the presence/absence of the synthetic TLR2 ligand Pam3CSK4 (10 ng/ml) for 24 h, whereupon G-CSF, CCL2, and IL-1β production was measured by ELISA. Results are from one experiment (n = 3 biological replicates/treatment) that was independently replicated four times and analyzed by unpaired Student’s t test (*p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001)