GFAP and amyotrophic lateral sclerosis: The pattern of correlations in the ALS hippocampus mirrored that of the control motor cortex and hippocampus; strong or very strong statistically significant correlations were observed between the percentages of CD68high and L-ferritinhigh microglia (r = 0.817, p = 0.0108), CD74high and HLA-DRhigh microglia (r = 0.850, p = 0.00610), Iba1high and L-ferritinhigh microglia (r = − 0.817, p = 0.0108), Iba1high CD68high microglia (r = − 0.883, p = 0.00310), and HLA-DRhigh microglia and GFAP load (r = 0.683, p = 0.0503), although this did not reach statistical significance.