Fig. 1

Fibronectin aggregates and plasma fibronectin tend to promote proliferation of microglia. 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). Subsequently, proliferation was determined by allowing the cells to incorporate BrdU for 24 h. BrdU-positive cells (green) that also expressed Iba1 (red, microglia, a) or isolectin-B4 (red, IB4, macrophages, c) were counted. Compared to control microglia culturing on pFn and aFn coatings tend to enhance proliferation of microglia, similarly as observed upon IL-4 treatment (b). Conversely, compared to control macrophages, proliferation of BMDMs on pFn and aFn coatings was hardly affected, while IFNγ tends to decrease BMDM proliferation (d). Bars in b and d represent mean percentages of cells incorporating BrdU from three (microglia) to four (macrophage) independent experiments. Error bars show standard errors of the mean. Statistical analyses were performed using one-way ANOVA (not significant). Scale bar is 10 μm