Fig. 1

Activated microglia express MCP1 in the motor cortex of ALS patients. Representative images of layer V of the motor cortex isolated from postmortem normal controls and ALS patients. a Normal controls have large Betz cells (Map2+) located in layer V of the motor cortex, with no evidence of gliosis. Inset is enlarged to the right. b, c sALS and fALS cases have smaller Betz cells (Map2+) and microgliosis (Iba1+), and astrogliosis (GFAP+) is observed. Insets are enlarged to the right. d Normal controls have low levels of MCP1 expression. Inset is enlarged at the bottom. e–g sALS and fALS cases have high levels of MCP1, and MCP1+ cells co-localize with activated microglia (Iba1+). Insets are enlarged at the bottom. h Graph represents average number or microglia per section ± SEM in normal controls (black column), sALS (white column), and fALS (grey column). i Graph represents percentage of normal microglia per section ± SEM in normal controls (black column), sALS (white column), and fALS (grey column). j Graph represents percentage of activated microglia per section ± SEM in normal controls (black column), sALS (white column), and fALS (grey column). *p < 0.05, **p < 0.01. Number sign marks normal microglia; arrows point to activated microglia; arrowheads point to rod-like microglia. Abbreviations: sALS sporadic ALS, fALS familial ALS. Scale bar = 10 μm (a–c), scale bar = 20 μm (d–g)