Cytokine mixtures from SFM, LTA or LPS conditioned media had no effect on fibrocyte differentiation. Human PBMCs were cultured in the absence of added cytokines (control) or in mixtures of cytokines (IL-6, TNF-α, granulocyte colony-stimulating factor (G-CSF), tumor growth factor (TGF)-β1, and IFN-γ) at the concentrations found in conditioned media from SFM-, LTA-, or LPS-treated PBMCs. Human PBMCs were also cultured in the presence of mixtures containing 1000 pg/ml, 500 pg/ml, 100 pg/ml, or 10 pg/ml of each of the five cytokines. After 5 days, the cells were dried, fixed and stained, and the number of fibrocytes was counted. The results are means ± SEM of fibrocytes per 2.5 × 105 PBMCs. (A). Results from one donor. (B) Results from a second donor. For each donor, there was no significant difference between any cytokine mixture and the control (1-way ANOVA, Dunnett's test and t-test).