Fig. 4

Fibronectin aggregates and plasma fibronectin do not significantly alter cytokine and chemokine gene expression, representative of classically or alternatively activated phenotypes, in microglia and bone marrow-derived macrophages. Microglia (a, b) or bone marrow-derived macrophages (BMDMs, c, d) were left unstimulated (ctrl), cultured on plasma fibronectin (pFn) or fibronectin aggregates (aFn), or treated with interferon-γ (IFNγ) or interleukin-4 (IL-4) for 6 h, after which total RNA was extracted. Cytokine and chemokine gene expression levels were analyzed using quantitative real-time PCR against pro-inflammatory markers for the classically activated phenotype (a, c, tumor necrosis factor-α (TNFα), interleukin-1β (IL-1β) and interleukin-12 (IL-12)) and an anti-inflammatory marker for the alternatively activated phenotype (b, d, arginase-1 (arg-1)) against HMBS (shown) and GAPDH (not shown, but yielding comparable findings). Bars represent mean expression levels versus control (set at 1 for each independent experiment, horizontal line) from three independent experiments. Error bars show the standard error of the mean. Statistical analyses were performed using the one-sample t test when compared to control (*p < 0.05; **p < 0.01)