Fig. 1

GM-CSF induces proliferation of noninflammatory microglia. a Experimental schedule. Slice cultures were chronically exposed to GM-CSF (100 ng/mL), GM-CSF+LPS (100 ng/mL, both) and IFN-γ+LPS (100 ng/mL, both) for 72 h from DIV 8 to DIV 11. b Iba1 immunoreactivity in naïve control (CTL) and GM-CSF slices. Images were taken from the hippocampal CA3 region (see scheme in Fig. 2c). c Quantification of Iba1-positive cells. Microglia counting was performed using a stereology-based method. d Nitrite accumulation in culture supernatants. e IL-6 and f TNF-α release. Note the difference in NO release between GM-CSF+LPS and IFN-γ+LPS (d). For c, values represent medians and interquartile range and the whiskers indicate minimum and maximum of data and were compared using unpaired t-tests. For d–f, values represent averages ± SEM and were compared using one-way ANOVA followed by Tukey’s post-test *P < 0.05 vs. CTL; #P < 0.05 vs. GM-CSF; +P < 0.05 vs. GM-CSF+LPS. For n/N cultures/preparations: b CTL, 31/8; GM-CSF, 27/7. c CTL, 7/2; GM-CSF, 7/2. d CTL, 8/5; GM-CSF, 10/5; GM-CSF+LPS, 6/3; IFN-γ+LPS, 4/3. e CTL, 4/4; GM-CSF, 10/4; GM-CSF+LPS, 6/3; IFN-γ+LPS, 3/3. f CTL, 6/4; GM-CSF, 10/5; GM-CSF+LPS, 6/3; IFN-γ+LPS, 4/3